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	<title>Math Goes Pop! &#187; Math on TV</title>
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		<title>An Introduction to Pumpkin Chunkin&#8217;</title>
		<link>http://www.mathgoespop.com/2011/12/an-introduction-to-pumpkin-chunkin.html</link>
		<comments>http://www.mathgoespop.com/2011/12/an-introduction-to-pumpkin-chunkin.html#comments</comments>
		<pubDate>Thu, 08 Dec 2011 19:23:58 +0000</pubDate>
		<dc:creator>Matt</dc:creator>
				<category><![CDATA[Holidays]]></category>
		<category><![CDATA[Math on TV]]></category>
		<category><![CDATA[hooke's law]]></category>
		<category><![CDATA[modern family]]></category>
		<category><![CDATA[physics]]></category>
		<category><![CDATA[thanksgiving]]></category>

		<guid isPermaLink="false">http://www.mathgoespop.com/?p=1561</guid>
		<description><![CDATA[<p>In a recent episode of ABC&#8217;s Modern Family, Cameron and Mitchell (the show&#8217;s unambiguously gay duo) are with some friends talking about Thanksgiving when Cameron decides to tell a story from his youth which, in his opinion, is quite compelling.  Mitchell knows better, but doesn&#8217;t have the heart to tell him that this particular story suffers <span style="color:#777"> . . . &#8594; Read More: <a href="http://www.mathgoespop.com/2011/12/an-introduction-to-pumpkin-chunkin.html">An Introduction to Pumpkin Chunkin&#8217;</a></span>]]></description>
			<content:encoded><![CDATA[<p>In a recent episode of ABC&#8217;s <a href="http://en.wikipedia.org/wiki/Modern_Family">Modern Family</a>, Cameron and Mitchell (the show&#8217;s unambiguously gay duo) are with some friends talking about Thanksgiving when Cameron decides to tell a story from his youth which, in his opinion, is quite compelling.  Mitchell knows better, but doesn&#8217;t have the heart to tell him that this particular story suffers from some basic structural flaws.  As Mitchell puts it, the story can be summarized as follows: &#8220;Once Cam and his friends tried to slingshot a pumpkin across a football field.  Three seconds.  That&#8217;s all you need to tell that story.&#8221;  Readers in the U.S. can see the full clip below:</p>
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<p>Needless to say, Cameron&#8217;s version of the story is much more embellished. In his rendition, their experiment was a success; as he puts it, the pumpkin flew across the field, &#8220;goal post to goal post.&#8221;</p>
<p>When I first heard him say this, my initial thought was &#8220;Is Cameron telling the truth?&#8221;  How likely is it that a pumpkin, launched from a slingshot at one end of a football field, could sail through the air to land on the other side?  Note that his story actually ends with the pumpkin falling through the sun roof of someone&#8217;s car &#8211; this outcome is, of course, highly implausible, and therefore casts a shadow of doubt upon the entire story.  While the sunroof claim would be difficult to verify, one can at least use some basic math and physics to test the plausibility of the first portion of the story.</p>
<p>We would like to be able to find a formula for the distance Cameron&#8217;s pumpkin should travel.  Key to our analysis is the <a href="http://en.wikipedia.org/wiki/Conservation_of_energy">conservation of energy</a> principle, and <a href="http://en.wikipedia.org/wiki/Hooke%27s_law">Hooke&#8217;s Law</a>.  In particular, we will assume that the slingshot behaves like a spring, i.e. the potential energy it stores is proportional to the square of the displacement (for example, stretching the slingshot two meters gives you four times the potential energy as stretching it one meter).  So, if Cameron and his friends stretched the slingshot a distance of <em>x</em> meters, the slingshot would then store a potential energy of <img src='http://s.wordpress.com/latex.php?latex=%5Cfrac%7B1%7D%7B2%7Dkx%5E%7B2%7D&#038;bg=T&#038;fg=000000&#038;s=0' alt='\frac{1}{2}kx^{2}' title='\frac{1}{2}kx^{2}' class='latex' />, where <em>k</em> is the spring constant and depends on the physical properties of the slingshot.</p>
<p>Now let us invoke the conservation of energy principle: when the slingshot is released, suppose all that stored potential energy will be converted into the kinetic energy of the pumpkin.  The formula for the kinetic energy of an object is <img src='http://s.wordpress.com/latex.php?latex=%5Cfrac%7B1%7D%7B2%7Dmv%5E%7B2%7D&#038;bg=T&#038;fg=000000&#038;s=0' alt='\frac{1}{2}mv^{2}' title='\frac{1}{2}mv^{2}' class='latex' />, where <em>m</em> is the object&#8217;s mass, and <em>v</em> is the object&#8217;s velocity.  So, when the pumpkin is released, by conservation of energy, this kinetic energy should be the same as the potential energy the system had before we chunked the pumpkin.  In other words,</p>
<p style="text-align: center;"><img src='http://s.wordpress.com/latex.php?latex=%5Cfrac%7B1%7D%7B2%7Dkx%5E%7B2%7D%20%3D%20%5Cfrac%7B1%7D%7B2%7Dmv%5E%7B2%7D&#038;bg=T&#038;fg=000000&#038;s=0' alt='\frac{1}{2}kx^{2} = \frac{1}{2}mv^{2}' title='\frac{1}{2}kx^{2} = \frac{1}{2}mv^{2}' class='latex' />,</p>
<p style="text-align: left;">which, with a bit of algebra, tells us that the initial velocity of the pumpkin when it comes out of the slingshot must be <img src='http://s.wordpress.com/latex.php?latex=x%5Csqrt%7B%5Cfrac%7Bk%7D%7Bm%7D%7D&#038;bg=T&#038;fg=000000&#038;s=0' alt='x\sqrt{\frac{k}{m}}' title='x\sqrt{\frac{k}{m}}' class='latex' />.</p>
<p style="text-align: left;">&nbsp;</p>
<div id="attachment_1572" class="wp-caption aligncenter" style="width: 610px"><a href="http://en.wikipedia.org/wiki/File:Pumpkins.jpg"><img class="size-full wp-image-1572" title="Pumpkins" src="http://www.mathgoespop.com/wp-content/uploads/2011/12/Pumpkins.jpg" alt="" width="600" height="433" /></a><p class="wp-caption-text">These poor little guys have no idea what&#39;s in store for them.</p></div>
<p style="text-align: left;">So we have an equation for the velocity of the pumpkin in terms of the spring constant <em>k</em>, the distance <em>x</em> we pull the slingshot, and the mass <em>m</em> of the pumpkin.  Let&#8217;s not forget our main goal, though &#8211; what we&#8217;re ultimately interested in isn&#8217;t a formula for the initial velocity of the pumpkin, but rather the distance the pumpkin travels.  With a little more physics, it&#8217;s not hard to get from one of these pieces of information to the other.</p>
<p style="text-align: left;">More specifically, we have a very good understanding of <a href="http://en.wikipedia.org/wiki/Trajectory_of_a_projectile">projectile motion</a>.  As I&#8217;ve discussed <a href="http://www.mathgoespop.com/2010/09/scott-pilgrim-vs-gravity.html">before</a>, if one ignores air resistance (as we will do for now), all the equations of projectile motion can be derived from the fact that the acceleration due to gravity is a constant, <img src='http://s.wordpress.com/latex.php?latex=g%20%5Capprox%209.8&#038;bg=T&#038;fg=000000&#038;s=0' alt='g \approx 9.8' title='g \approx 9.8' class='latex' /> meters per second per second.</p>
<p style="text-align: left;">Using this fact, suppose you throw an object with an initial velocity <img src='http://s.wordpress.com/latex.php?latex=v_%7B0%7D&#038;bg=T&#038;fg=000000&#038;s=0' alt='v_{0}' title='v_{0}' class='latex' /> at an angle <img src='http://s.wordpress.com/latex.php?latex=%5Ctheta&#038;bg=T&#038;fg=000000&#038;s=0' alt='\theta' title='\theta' class='latex' /> to the horizontal.  Then if one sets the initial position of the object to have coordinates (0,0), the <em>x</em>-coordinate of the object at any time <em>t</em> will be given by <img src='http://s.wordpress.com/latex.php?latex=tv_%7B0%7D%5Ccos%28%5Ctheta%29&#038;bg=T&#038;fg=000000&#038;s=0' alt='tv_{0}\cos(\theta)' title='tv_{0}\cos(\theta)' class='latex' />, and the <em>y</em>-coordinate of the object at any time <em>t </em>will be given by <img src='http://s.wordpress.com/latex.php?latex=tv_%7B0%7D%5Csin%28%5Ctheta%29%20-%20%5Cfrac%7B1%7D%7B2%7Dgt%5E%7B2%7D&#038;bg=T&#038;fg=000000&#038;s=0' alt='tv_{0}\sin(\theta) - \frac{1}{2}gt^{2}' title='tv_{0}\sin(\theta) - \frac{1}{2}gt^{2}' class='latex' />.  Using these formulas and a bit more algebra, one can determine that the distance <em>d</em> an object will travel in the <em>x</em> direction can be written in terms of the initial velocity, the angle <img src='http://s.wordpress.com/latex.php?latex=%5Ctheta&#038;bg=T&#038;fg=000000&#038;s=0' alt='\theta' title='\theta' class='latex' />, and <em>g</em>, via the formula</p>
<p style="text-align: center;"><img src='http://s.wordpress.com/latex.php?latex=d%20%3D%20%5Cfrac%7Bv_%7B0%7D%5E%7B2%7D%5Csin%282%5Ctheta%29%7D%7Bg%7D.&#038;bg=T&#038;fg=000000&#038;s=0' alt='d = \frac{v_{0}^{2}\sin(2\theta)}{g}.' title='d = \frac{v_{0}^{2}\sin(2\theta)}{g}.' class='latex' /></p>
<p style="text-align: center;">&nbsp;</p>
<div id="attachment_1575" class="wp-caption aligncenter" style="width: 419px"><a href="http://www.mathgoespop.com/wp-content/uploads/2011/12/Picture-9.png"><img class="size-full wp-image-1575" title="Picture 9" src="http://www.mathgoespop.com/wp-content/uploads/2011/12/Picture-9.png" alt="" width="409" height="306" /></a><p class="wp-caption-text">Example trajectory of an object shot with an initial velocity v at an angle A.  The distance the object travels in the x direction is given by the above formula.</p></div>
<p style="text-align: left;">To recap: we have the distance as a function of the initial velocity, the angle the pumpkin is shot from, and the acceleration due to gravity.  We also have the initial velocity in terms of the distance the slingshot is stretched, the mass of the pumpkin, and the spring constant.  Combining these two formulas, we find that</p>
<p style="text-align: center;"><img src='http://s.wordpress.com/latex.php?latex=d%20%3D%20%5Cfrac%7Bkx%5E%7B2%7D%5Csin%282%5Ctheta%29%7D%7Bmg%7D%2C&#038;bg=T&#038;fg=000000&#038;s=0' alt='d = \frac{kx^{2}\sin(2\theta)}{mg},' title='d = \frac{kx^{2}\sin(2\theta)}{mg},' class='latex' /></p>
<p style="text-align: left;">and we now have the desired formula for the distance the pumpkin travels.</p>
<p>Let&#8217;s check Cameron&#8217;s story against this formula.  If the pumpkin really went from goal post to goal post, the distance it traveled in the <em>x </em>direction must have been at least 120 yards (100 yards for the field of play, plus 10 yards for each end zone).  This is roughly 109.7 meters.  Therefore, we must have <img src='http://s.wordpress.com/latex.php?latex=d%20%5Cgeq%20109.7&#038;bg=T&#038;fg=000000&#038;s=0' alt='d \geq 109.7' title='d \geq 109.7' class='latex' />.</p>
<p>On the right side of the equation, the term <img src='http://s.wordpress.com/latex.php?latex=%5Csin%282%5Ctheta%29&#038;bg=T&#038;fg=000000&#038;s=0' alt='\sin(2\theta)' title='\sin(2\theta)' class='latex' /> is maximized when <img src='http://s.wordpress.com/latex.php?latex=%5Ctheta&#038;bg=T&#038;fg=000000&#038;s=0' alt='\theta' title='\theta' class='latex' /> equals 45°, and in this case <img src='http://s.wordpress.com/latex.php?latex=%5Csin%2890%29%3D1&#038;bg=T&#038;fg=000000&#038;s=0' alt='\sin(90)=1' title='\sin(90)=1' class='latex' />.  So after making this simplification, we see that in order for Cameron&#8217;s story to be true, it must be the case that</p>
<p style="text-align: center;"><img src='http://s.wordpress.com/latex.php?latex=%5Cfrac%7Bkx%5E%7B2%7D%7D%7Bmg%7D%20%5Cgeq%20109.7.&#038;bg=T&#038;fg=000000&#038;s=0' alt='\frac{kx^{2}}{mg} \geq 109.7.' title='\frac{kx^{2}}{mg} \geq 109.7.' class='latex' /></p>
<p style="text-align: left;">The acceleration due to gravity is known, but we need to provide estimates for <em>m, k,</em> and <em>x</em>.  The mass <em>m</em> is the easiest to estimate; let&#8217;s say the pumpkin is around 10 pounds (roughly 4.5 kilograms).  To be generous, we&#8217;ll even round down to 4 kilograms.  What about the distance the slingshot is stretched?  Based on the slingshot used in the episode, it&#8217;s unlikely the slingshot in Cameron&#8217;s story would have been stretched more than 2 meters or so, but let&#8217;s again be generous and say it&#8217;s stretched 3 meters.  Plugging in these values, we would have:</p>
<p style="text-align: center;"><img src='http://s.wordpress.com/latex.php?latex=k%20%5Cgeq%20109.7%20%5Ccdot%204%20%5Ccdot%209.8%2F9%20%5Capprox%20478%2C&#038;bg=T&#038;fg=000000&#038;s=0' alt='k \geq 109.7 \cdot 4 \cdot 9.8/9 \approx 478,' title='k \geq 109.7 \cdot 4 \cdot 9.8/9 \approx 478,' class='latex' /></p>
<p style="text-align: left;">where the units on <em>k</em> are Newtons per meter.  Since one pound is approximately 4.45 newtons, this is saying that the spring constant is about 107 pounds per meter &#8211; in other words, for each meter you stretch the slingshot, you need to exert 107 pounds of force.  To put it another way, to stretch the slingshot 3 meters or more, you&#8217;d need to exert 321 pounds of force.</p>
<p style="text-align: left;">This seems like quite a lot, though Cameron is a large fellow.  But recall we were being generous, both in our computation of the spring constant and in our estimate of the pumpkin size.  We also neglected air resistance in this model, but air resistance probably has a non-negligible impact here &#8211; not only will it slow down the pumpkin&#8217;s forward motion, but it also decreases the optimal angle from 45°.  So in a real world situation, I&#8217;d have to remain skeptical of Cameron&#8217;s story.  On the other hand, these calculations don&#8217;t necessarily rule it out entirely (though a more sophisticated analysis might).</p>
<p style="text-align: left;">For more on the physics of pumpkin chunkin&#8217;, <a href="http://www.wired.com/wiredscience/2010/11/the-physics-of-punkin-chunkin/">here</a>&#8216;s an article from last year courtesy of Wired.  For related trajectory issues, Angry Birds also provides <a href="http://www.wired.com/wiredscience/2011/05/is-the-launch-speed-in-angry-birds-constant/">plenty</a> of fodder.</p>
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		<title>A Mathematics Community</title>
		<link>http://www.mathgoespop.com/2011/10/math-with-community.html</link>
		<comments>http://www.mathgoespop.com/2011/10/math-with-community.html#comments</comments>
		<pubDate>Sun, 16 Oct 2011 17:53:39 +0000</pubDate>
		<dc:creator>Matt</dc:creator>
				<category><![CDATA[Math Gets Around]]></category>
		<category><![CDATA[Math on TV]]></category>
		<category><![CDATA[community]]></category>
		<category><![CDATA[kickpuncher]]></category>
		<category><![CDATA[stable marriage problem]]></category>
		<category><![CDATA[stable roommate problem]]></category>

		<guid isPermaLink="false">http://www.mathgoespop.com/?p=1477</guid>
		<description><![CDATA[<p>Whether knowingly or not, NBC Thursday night comedies have made occasional dalliances with mathematics.  For example, you can see here for a mathematical discussion inspired by The Office, and here for one inspired by Parks and Recreation.</p>
<p>Today I would like to add to this esteemed list the show Community, now in its third season on NBC&#8217;s <span style="color:#777"> . . . &#8594; Read More: <a href="http://www.mathgoespop.com/2011/10/math-with-community.html">A Mathematics Community</a></span>]]></description>
			<content:encoded><![CDATA[<p>Whether knowingly or not, NBC Thursday night comedies have made occasional dalliances with mathematics.  For example, you can see <a href="http://www.mathgoespop.com/2011/05/dunder-math-lin.html">here</a> for a mathematical discussion inspired by <a href="http://en.wikipedia.org/wiki/The_Office_%28U.S._TV_series%29">The Office</a>, and <a href="http://www.mathgoespop.com/2011/05/parks-and-recreational-mathematics.html">here</a> for one inspired by <a href="http://en.wikipedia.org/wiki/Parks_and_Recreation">Parks and Recreation</a>.</p>
<p>Today I would like to add to this esteemed list the show <a href="http://en.wikipedia.org/wiki/Community_%28TV_series%29">Community</a>, now in its third season on NBC&#8217;s Thursday block.  As the title indicates, the show centers around a group of friends who are students at the fictional Greendale Community College (how this formula will pan out if the show lasts more than four seasons is uncertain).</p>
<p>In a recent episode (titled Competitive Ecology), the gang divides themselves up into pairs of lab partners for Biology class, but they quickly discover their pairings are less than ideal &#8211; especially since, with an odd number in the central crew, one member must pair up with someone who is not in their clique.  Their first assignment is to build a terrarium, and with the deadline quickly approaching, they need to find away to shuffle around the pairings and get their assignment done on time.</p>
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<p>Once they&#8217;ve decided to change partners, a debate ensues about the fairest way to switch up their initial pairings.  Finally, frequent ringleader Jeff Winger (played by <a href="http://en.wikipedia.org/wiki/Joel_McHale">Joel McHale</a>) proposes the following solution (note that Abed is another member of the central study group, while Todd is the outsider who found a turtle for his terrarium earlier in the episode):</p>
<blockquote><p>Ok, let&#8217;s make this simple, and do it like student housing.  Everyone  write down their lab partner preferences from one to eight.  Abed,  you&#8217;re a computer, you figure out a way to put us in our optimal  pairings.  And before you all go putting Todd down last, don&#8217;t forget,  he comes with a turtle &#8211; you&#8217;re halfway done.  How does that sound?</p></blockquote>
<p>Indeed, Jeff &#8211; the problem is more closely related to student housing than you imagine.  Before spoiling the math connection, though, allow me to show you the following dialogue, which takes place once Abed has determined the new pairings.</p>
<blockquote><p>Abed: Umm, all right.  Yep.  According to my system, Annie&#8217;s gonna be  with Shirley, Pierce is with me, Troy&#8217;s with Britta, and Jeff is with  Todd.</p>
<p>Annie: Okay, let&#8217;s get to work!</p>
<p>Jeff: Uhh, wait.  Umm, how did I end up with Todd?  No offense, but he wasn&#8217;t exactly at the top of my list.</p>
<p>Todd: None taken.</p>
<p>Abed: It&#8217;s what the algorithm dictated.</p>
<p>Jeff: And we&#8217;re just supposed to trust your algorithm?</p>
<p>Abed: Are you questioning my algorithm?</p>
<p>Jeff: Not necessarily &#8211; is your algorithm above questioning?</p>
<p>Abed: Not necessarily.</p>
<p>Jeff: Will you just tell us how you chose?</p>
<p>Abed: I used the ballots to rank everyone by popularity, and I put  the most popular with the least popular.  I figured it would maximize  each partnership&#8217;s audience appeal.</p>
<p>Jeff: Oh, I see. So I was number one, and he was obviously number eight, no offense Todd.</p>
<p>Abed: You and Todd were four and five.</p>
<p>Jeff: I was <em>four</em>?</p>
<p>Abed: Todd was four.</p>
<p>Jeff: I was <em>five</em>?</p></blockquote>
<p>More significant than the dent to Jeff&#8217;s ego, however, should be the dent to Abed&#8217;s for his naïve approach to solving this problem.  Ironically, though he claims that Abed is a computer, it is Jeff&#8217;s remark that has the most prescience.  For indeed, this problem is well known as the <a href="http://en.wikipedia.org/wiki/Stable_roommates_problem">stable roommates problem</a>, and has already been studied quite a bit.</p>
<p>More important than &#8220;audience appeal&#8221; from a mathematical standpoint is the stability of the final pairing.  Roughly speaking, a collection of pairings is said to be <em>stable</em> if no two people from two separate pairs would rather be paired up with each other.  For example, in Abed&#8217;s final pairing, if Jeff prefers Annie to Todd and Annie prefers Jeff to Shirley, then Abed&#8217;s collection isn&#8217;t stable, because Annie and Jeff would both be happier if they swapped partners.</p>
<p>An algorithm to solve this problem was discovered in 1985.  The algorithm is explained in the Wikipedia link above, but let&#8217;s see an example of it in action using the Community cast as a starting point.  To keep things simple, let me suppose there are only four people instead of eight: say, Annie, Jeff, Troy, and Britta.</p>
<p>First, note that a stable solution to this problem is not always possible.  For example, suppose everyone grows weary of Jeff&#8217;s hubris, and so he ranks last in everyone&#8217;s list of preferences.  Then we may be given the following scenario:</p>

<table id="wp-table-reloaded-id-5-no-1" class="wp-table-reloaded wp-table-reloaded-id-5">
<thead>
	<tr class="row-1 odd">
		<th class="column-1">Name</th><th class="column-2">First Choice</th><th class="column-3">Second Choice</th><th class="column-4">Third Choice</th>
	</tr>
</thead>
<tbody>
	<tr class="row-2 even">
		<td class="column-1">Annie</td><td class="column-2">Britta</td><td class="column-3">Troy</td><td class="column-4">Jeff</td>
	</tr>
	<tr class="row-3 odd">
		<td class="column-1">Britta</td><td class="column-2">Troy</td><td class="column-3">Annie</td><td class="column-4">Jeff</td>
	</tr>
	<tr class="row-4 even">
		<td class="column-1">Jeff</td><td class="column-2">Troy</td><td class="column-3">Annie</td><td class="column-4">Britta</td>
	</tr>
	<tr class="row-5 odd">
		<td class="column-1">Troy</td><td class="column-2">Annie</td><td class="column-3">Britta</td><td class="column-4">Jeff</td>
	</tr>
</tbody>
</table>

<p>In this scenario, everyone aside from Jeff ranks Jeff last, and we also have a cycle (Annie is Troy&#8217;s first choice, Troy is Britta&#8217;s first choice, and Britta is Annie&#8217;s first choice).  In this case, there can be no stable solution.  For example, suppose Troy and Jeff are paired up, and Annie and Britta are paired up.  In this case, Troy would rather be with Britta, and vice versa.  Similarly, if Annie is stuck with Jeff, she would rather be with Troy, and vice versa, and if Britta is paired with Jeff, she would Annie, and vice versa.</p>
<p>Sometimes, however, solutions will exist.  Consider, for example, the following list of preferences:</p>

<table id="wp-table-reloaded-id-6-no-1" class="wp-table-reloaded wp-table-reloaded-id-6">
<thead>
	<tr class="row-1 odd">
		<th class="column-1">Name</th><th class="column-2">First Choice</th><th class="column-3">Second Choice</th><th class="column-4">Third Choice</th>
	</tr>
</thead>
<tbody>
	<tr class="row-2 even">
		<td class="column-1">Annie</td><td class="column-2">Britta</td><td class="column-3">Jeff</td><td class="column-4">Troy</td>
	</tr>
	<tr class="row-3 odd">
		<td class="column-1">Britta</td><td class="column-2">Troy</td><td class="column-3">Jeff</td><td class="column-4">Annie</td>
	</tr>
	<tr class="row-4 even">
		<td class="column-1">Jeff</td><td class="column-2">Annie</td><td class="column-3">Troy</td><td class="column-4">Britta</td>
	</tr>
	<tr class="row-5 odd">
		<td class="column-1">Troy</td><td class="column-2">Annie</td><td class="column-3">Britta</td><td class="column-4">Jeff</td>
	</tr>
</tbody>
</table>

<p>In this case, a stable solution is found in the following way: first, we go in order and list everyone&#8217;s first choice (this is the proposal round).  In the event that someone receives a second proposal, that person will reject the person who is lower on their preference list, and the rejected person will then ask the next person on their list.</p>
<p>Given the list above, here&#8217;s how things will go down: Annie will propose to Britta, Britta will propose to Troy, Jeff will propose to Annie, and Troy will propose to Annie.  Since Jeff is higher on Annie&#8217;s list than Troy, Annie will reject Troy, at which point Troy will propose to Britta.  Britta will then reject Annie&#8217;s proposal, and Annie will propose to Jeff.  This gives the pairing of Jeff with Annie and Britta with Troy, and this is stable.</p>
<p>For larger groups of people, the algorithm may need to go into a second stage after the proposal round.  Try a ranking with all eight zany characters and see what happens!</p>
<p style="text-align: center;"><object width="512" height="288"><param name="movie" value="http://www.hulu.com/embed/M1QOZh7gDS2vLz3HGyRD4w" /><param name="allowFullScreen" value="true" /><embed type="application/x-shockwave-flash" width="512" height="288" src="http://www.hulu.com/embed/M1QOZh7gDS2vLz3HGyRD4w" allowfullscreen="true"></embed></object></p>
<p>Note that this problem is closely related to the<a href="http://en.wikipedia.org/wiki/Stable_marriage_problem"> stable marriage problem</a>, with one key difference &#8211; in the stable marriage problem, the group is always cut in half along gender lines (males and females), so each person only provides a ranking of the members of the opposite sex.  Interestingly, this problem always has a stable solution, and its application goes beyond sorting people into couples &#8211; it is used, for instance, in the pairing of medical students with hospitals for residency.</p>
<p>So, sorry Abed, but you are not a computer after all.  But perhaps after reading this, you will be one step closer to the cyborg in Kickpuncher who you idolize so dearly.</p>
<div id="attachment_1500" class="wp-caption aligncenter" style="width: 308px"><a href="http://www.mathgoespop.com/wp-content/uploads/2011/10/Picture-6.png"><img class="size-full wp-image-1500" title="Kickpuncher" src="http://www.mathgoespop.com/wp-content/uploads/2011/10/Picture-6.png" alt="" width="298" height="457" /></a><p class="wp-caption-text">His cyberpunches have the power of kicks!</p></div>
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		<title>Four Weddings and Some Statistics</title>
		<link>http://www.mathgoespop.com/2011/08/four-weddings-and-some-statistics.html</link>
		<comments>http://www.mathgoespop.com/2011/08/four-weddings-and-some-statistics.html#comments</comments>
		<pubDate>Wed, 17 Aug 2011 17:46:59 +0000</pubDate>
		<dc:creator>Matt</dc:creator>
				<category><![CDATA[Math Gets Around]]></category>
		<category><![CDATA[Math on TV]]></category>
		<category><![CDATA[statistics]]></category>
		<category><![CDATA[weddings]]></category>

		<guid isPermaLink="false">http://www.mathgoespop.com/?p=1347</guid>
		<description><![CDATA[<p>When my fiancee was in the midst of the wedding planning, part of her research (or perhaps it was simply a guilty pleasure) involved watching wedding shows on basic cable.  For those of you who have not had the pleasure, between stations like WE tv and TLC, there are no fewer than nine different wedding-themed reality <span style="color:#777"> . . . &#8594; Read More: <a href="http://www.mathgoespop.com/2011/08/four-weddings-and-some-statistics.html">Four Weddings and Some Statistics</a></span>]]></description>
			<content:encoded><![CDATA[<p>When my fiancee was in the midst of the wedding planning, part of her research (or perhaps it was simply a guilty pleasure) involved watching wedding shows on basic cable.  For those of you who have not had the pleasure, between stations like <a href="http://www.wetv.com/">WE tv</a> and <a href="http://tlc.discovery.com/">TLC</a>, there are no fewer than nine different wedding-themed reality shows airing weekly.  Many of them are appealing in a rubbernecking sort of way; much like a car crash, the spectacle is too ridiculous to turn away from (I&#8217;m looking at you, <a href="http://tlc.howstuffworks.com/tv/my-big-fat-gypsy-wedding">My Big Fat Gypsy Wedding</a>).</p>
<p style="text-align: center;"><object width="640" height="390"><param name="movie" value="http://www.youtube.com/v/2HAUmII_hcg?version=3&amp;hl=en_US" /><param name="allowFullScreen" value="true" /><param name="allowscriptaccess" value="always" /><embed type="application/x-shockwave-flash" width="640" height="390" src="http://www.youtube.com/v/2HAUmII_hcg?version=3&amp;hl=en_US" allowscriptaccess="always" allowfullscreen="true"></embed></object></p>
<p>Of all of these shows, though, the one that most piques my mathematical interest is TLC&#8217;s <a href="http://en.wikipedia.org/wiki/Four_Weddings">Four Weddings</a>.  Based on a British show with the same name, the premise is as follows: four brides-to-be, unknown to one another, meet and attend each others&#8217; weddings.  When one bride gets married, the other three score various aspects of the wedding, and the bride with the highest score among the four wins a honeymoon (contingencies are in place in the event of a tie, though these are not always explained and seem to vary from season to season).  In order to make for good TV, the show frequently manages to bring out the worst aspects of these women, as they nitpick and pass judgment on everyone else&#8217;s wedding.  Here&#8217;s a short clip to give you a taste for what this show is all about:</p>
<p style="text-align: center;"><object width="640" height="390"><param name="movie" value="http://www.youtube.com/v/PeI09kys09Q?version=3&amp;hl=en_US" /><param name="allowFullScreen" value="true" /><param name="allowscriptaccess" value="always" /><embed type="application/x-shockwave-flash" width="640" height="390" src="http://www.youtube.com/v/PeI09kys09Q?version=3&amp;hl=en_US" allowscriptaccess="always" allowfullscreen="true"></embed></object></p>
<p>How are the weddings scored?  This process is explained in detail during the course of each episode.  The wedding is broken down into four categories: dress, venue, food, and overall experience.  For overall experience, the other three brides in attendance give a score from 1 to 10 (though I&#8217;ve never seen a bride give another wedding a 10).  For the rest of the categories, though, the brides can only rank the weddings as being 1st, 2nd, or 3rd in the given category.  1st place gets 10 points, 2nd place gets 6, and 3rd gets 3.  The total possible number of points a wedding can score is therefore 120.  At the end of each episode, the scores for each bride are broken out in detail.  The wedding budget and headcount are provided as well.</p>
<p>After watching a few episodes, it seemed like the best way to ensure a win was to simply outspend your competitors.  Certainly a large budget can help improve the guest experience or score a hip dress, but I was curious as to what overall trend (if any) could be made between, say, money spent on a wedding and the wedding&#8217;s overall score.</p>
<p>With this noble goal in mind, I proceeded to DVR 28 episodes of this show.  After recording the scores for 112 weddings, some of my questions were as follows: is the amount a person spends on a wedding correlated to the score they receive from the other competitors?  What about the amount a person spends <em>per guest</em>?  Finally, did the most expensive wedding win more frequently than would be expected by pure chance?</p>
<p>Let&#8217;s look at some data.  Here is a scatterplot of each wedding&#8217;s budget, vs. the total points earned.</p>
<div id="attachment_1357" class="wp-caption aligncenter" style="width: 620px"><a href="http://www.mathgoespop.com/wp-content/uploads/2011/08/Picture-5.png"><img class="size-full wp-image-1357" title="CostVsScore" src="http://www.mathgoespop.com/wp-content/uploads/2011/08/Picture-5.png" alt="" width="610" height="311" /></a><p class="wp-caption-text">Click to embiggen!</p></div>
<p>As the dots suggest, there is a slight positive correlation between the amount one spends on a wedding, and the score one receives from one&#8217;s fellow competitors.  The <a href="http://en.wikipedia.org/wiki/Pearson_product-moment_correlation_coefficient">coefficient of correlation</a> here is approximately 0.286, though if we discard the two $150,000 weddings, this improves to around 0.348.</p>
<p>Of course, a $10,000 wedding for 10 people might be a much nicer affair than a $10,000 wedding for 1,000 people.  If you spend more money per guest, does this translate into a higher score as well?  The dots don&#8217;t lie; here&#8217;s another scatterplot:</p>
<div id="attachment_1359" class="wp-caption aligncenter" style="width: 649px"><a href="http://www.mathgoespop.com/wp-content/uploads/2011/08/Picture-6.png"><img class="size-full wp-image-1359" title="CPGvsScore" src="http://www.mathgoespop.com/wp-content/uploads/2011/08/Picture-6.png" alt="" width="639" height="326" /></a><p class="wp-caption-text">Click to embiggen!</p></div>
<p>There is quite clearly an outlier in this set of data &#8211; this corresponds to a bride who spent $150,000 for a 120 person wedding, for a whopping $1,250 spent per guest (this particular bride did end up taking first place).  Eliminating this outlier, though, the correlation here is weaker than the correlation for actual cost, at a meager 0.098.  In other words, there may not be a linear relationship between cost per guest and total score.  This may be because certain fixed costs, such as the dress and the venue, won&#8217;t necessarily vary much with the guest total, unlike something like food.</p>
<p>This analysis, though, obscures a key point.  In order to win the honeymoon, you don&#8217;t necessarily need a high score; you only need a higher score than your three other competitors.  With this in mind, it may be simpler to just look at the scores episode-by-episode, and see how the amount spent on a wedding compares to the wedding&#8217;s relative ranking.</p>
<p>In the graph below, the blue bars count the number of times the most expensive wedding was given a certain rank.  The red bars count the number of times the wedding with the highest cost per guest was given a certain rank.  Note that if cost had no bearing on the rank, we would expect an equal number of weddings in each rank (in this case, about 7 per rank).</p>
<div id="attachment_1362" class="wp-caption aligncenter" style="width: 649px"><a href="http://www.mathgoespop.com/wp-content/uploads/2011/08/Picture-7.png"><img class="size-full wp-image-1362" title="costranks" src="http://www.mathgoespop.com/wp-content/uploads/2011/08/Picture-7.png" alt="" width="639" height="336" /></a><p class="wp-caption-text">Click to embiggen!</p></div>
<p>As you can see, spending the most money seems to bestow an advantage: fully 50% (14 out of 28) of the most expensive weddings were ranked first.  This would be unlikely if cost had no impact on ranking.</p>
<p>The picture is a little murkier for cost per guest -the frequency for each ranking sticks pretty closely to 7, so it&#8217;s not clear that spending more per guest gives any advantage.</p>
<p>In conclusion, there is a small positive correlation between amount spent and score received, though this does not transfer to the amount spent per guest.  Compared only to one&#8217;s other three competitors, the amount spent appears to confer an even greater advantage, so if you are on this show and want to show your competitors that you are better than them, my advice would be to simply outspend them.  If all you&#8217;re interested in is a nice vacation, though, it may be cheaper to just stick to your budget, and plan a vacation on your own.</p>
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		<title>MTV/Oscar Showdown</title>
		<link>http://www.mathgoespop.com/2011/06/mtvoscar-showdown.html</link>
		<comments>http://www.mathgoespop.com/2011/06/mtvoscar-showdown.html#comments</comments>
		<pubDate>Thu, 09 Jun 2011 18:16:46 +0000</pubDate>
		<dc:creator>Matt</dc:creator>
				<category><![CDATA[Math in the Movies]]></category>
		<category><![CDATA[Math on TV]]></category>
		<category><![CDATA[mtv]]></category>
		<category><![CDATA[oscars]]></category>
		<category><![CDATA[statistics]]></category>
		<category><![CDATA[twilight]]></category>
		<category><![CDATA[voting]]></category>

		<guid isPermaLink="false">http://www.mathgoespop.com/?p=1263</guid>
		<description><![CDATA[<p>For many of us, summer is thought of as the time between Memorial Day and Labor Day.  For folks of a younger generation, though, trendier bookends are provided by two MTV Award shows: The Movie Awards at the beginning of the summer, and the Video Music Awards at the end.  Continuing this noble tradition, <span style="color:#777"> . . . &#8594; Read More: <a href="http://www.mathgoespop.com/2011/06/mtvoscar-showdown.html">MTV/Oscar Showdown</a></span>]]></description>
			<content:encoded><![CDATA[<p>For many of us, summer is thought of as the time between Memorial Day and Labor Day.  For folks of a younger generation, though, trendier bookends are provided by two MTV Award shows: <a href="http://en.wikipedia.org/wiki/MTV_Movie_Awards">The Movie Awards</a> at the beginning of the summer, and the <a href="http://en.wikipedia.org/wiki/MTV_Video_Music_Awards">Video Music Awards</a> at the end.  Continuing this noble tradition, the 20th iteration of the MTV Movie Awards was broadcast this weekend.  If you missed it, don&#8217;t worry; I&#8217;m sure it will be shown another 300,000 or so times before the summer is out.</p>
<p>As a shining beacon of what is hip, MTV has a responsibility during its movie awards to highlight the most popular films of the year.  This is in stark contrast to the priorities of higher brow award shows such as the Oscars, for which artistic achievement is placed on the highest pedestal.  This is not to say that these two goals need be mutually exclusive; indeed, since the first MTV Movie Awards was broadcast in 1992, the &#8220;Best Film&#8221; has agreed with the Academy Award winning best film three times (1997&#8242;s <a href="http://www.imdb.com/title/tt0120338/">Titanic</a>, 2000&#8242;s <a href="http://www.imdb.com/title/tt0172495/">Gladiator</a>, and 2003&#8242;s <a href="http://www.imdb.com/title/tt0167260/">Lord of the Rings: The Return of the King</a>).  Even so, a quick glance at the nominated films from these two awards shows each year reveals a fairly small overlap, in general.  But if MTV&#8217;s goal is to prop up films from an angle focused more on pop culture, it is natural to ask how good of a job they do.</p>
<div id="attachment_1268" class="wp-caption aligncenter" style="width: 234px"><a href="http://www.mtv.com/ontv/movieawards/2011/"><img class="size-medium wp-image-1268" title="mtvma" src="http://www.mathgoespop.com/wp-content/uploads/2011/06/mtvma-224x300.jpg" alt="" width="224" height="300" /></a><p class="wp-caption-text">Delicious metal popcorn. (Photo: Jason McDonald/MTV)</p></div>
<p>This question begets another one: how can we best measure a film&#8217;s popularity?  My first thought was to consider the rankings on <a href="http://www.imdb.com/">IMDB</a>.  There, users can give any film a score from 1 to 10; as a prime example of a <a href="http://rangevoting.org/">range voting</a> system, this seemed like a good place to measure the public&#8217;s reception of a film.</p>
<p>The results were mixed.  With this metric, comparing the 20 years that both awards shows have been around, the MTV best film scored higher than the Oscar winning best film only 5 times.  Oscar trumped 12 times, and the two awards tied three times.  The trend is also worth mentioning &#8211; after 5 consecutive years of beating or tying the Oscars in IMDB score from 1999-2003, the Oscar winning film has bested the MTV winning film ever since.  The disparity has become even larger in recent years (I call this the <a href="http://en.wikipedia.org/wiki/Twilight_%28series%29">Twilight</a> effect, as the Twilight films have won best film at the MTV awards for three years running).  Here&#8217;s a graph of the scores over time (the list of MTV Best film winners is <a href="http://en.wikipedia.org/wiki/MTV_Movie_Award_for_Best_Movie">here</a>; Oscar winners can be found <a href="http://en.wikipedia.org/wiki/Academy_Award_for_Best_Picture">here</a>):</p>
<p style="text-align: center;"><a href="http://www.mathgoespop.com/wp-content/uploads/2011/06/Screen-shot-2011-06-09-at-10.11.17-AM.png"><img class="size-full wp-image-1269 aligncenter" title="Screen shot 2011-06-09 at 10.11.17 AM" src="http://www.mathgoespop.com/wp-content/uploads/2011/06/Screen-shot-2011-06-09-at-10.11.17-AM.png" alt="" width="601" height="393" /></a></p>
<p>While you may argue there isn&#8217;t enough data here to draw much of a strong conclusion, the recent trend is fairly convincing.  By this metric, it seems like Oscar winning films, at least over the past few years, seem to have been more popular.</p>
<p>Rather than looking at only the winner, though, you might expect to get a better sense of the popularity of films on display by looking at all nominated films, rather than just the winners.  If we take the average IMDB score for all nominated best films at each awards show, rather than just the winning film, we get the following picture:</p>
<p style="text-align: center;"><a href="http://www.mathgoespop.com/wp-content/uploads/2011/06/Screen-shot-2011-06-09-at-10.19.18-AM.png"><img class="size-full wp-image-1270 aligncenter" title="AvgIMDB" src="http://www.mathgoespop.com/wp-content/uploads/2011/06/Screen-shot-2011-06-09-at-10.19.18-AM.png" alt="" width="600" height="386" /></a></p>
<p>It&#8217;s come close, but the average IMDB score of MTV nominated films has never been greater than the average IMDB score for Oscar nominated films.  We see the Twilight effect among the averages as well, though it was dampened somewhat this year due to the inclusion of critical darlings <a href="http://www.imdb.com/title/tt1375666/">Inception</a>, <a href="http://www.imdb.com/title/tt1285016/">The Social Network</a>, and <a href="http://www.imdb.com/title/tt0947798/">Black Swan</a> on the MTV nominee list.</p>
<p>&#8220;Hold up,&#8221; you may be thinking to yourself, &#8220;this is all a bunch of hooey.&#8221;  You may think that IMDB scores are not a very good measure of a film&#8217;s popularity.  It may be quite likely that IMDB scores are biased towards those same features of a film that make it more likely for Oscar consideration.  Perhaps the type of person who goes onto the website to rate films is more likely to be somewhat of a connoisseur, and therefore the tastes reflected by the IMDB community are more likely to reflect the tastes of the Oscars.  At the very least, it seems likely that teenage girls are not voting on the website in droves; how else can one explain the Twilight series&#8217; limp average of only 4.9?</p>
<p>What else can we use to measure a film&#8217;s popularity?  Well, to return to teenage girls, they don&#8217;t show their support for the Twilight series by rating it highly on the internet.  They show their support by going out and seeing the movie multiple times.  So perhaps we should look at box office receipts rather than IMDB score (and, of course, by picking sides in the bitter feud between Edward and Jacob).  What sort of picture do we see in this case?</p>
<p>If we only consider the winning film from each awards show, the data looks like this (I&#8217;m only considering US box office numbers here):</p>
<p><a href="http://www.mathgoespop.com/wp-content/uploads/2011/06/Screen-shot-2011-06-09-at-10.39.40-AM.png"><img class="aligncenter size-full wp-image-1271" title="BestMoney" src="http://www.mathgoespop.com/wp-content/uploads/2011/06/Screen-shot-2011-06-09-at-10.39.40-AM.png" alt="" width="600" height="385" /></a>(I&#8217;ve cut the graph so that you can&#8217;t see the leap in 1997, when Titanic took top prize at both shows.)  Things look a little more erratic, but if you look closely, you&#8217;ll see that the MTV award winner has taken in more money than its Oscar winning counterpart 14 times out of 20.  The Oscar has favored the larger cash cow only three times.</p>
<p>As with the IMDB rankings, we can try to smooth things out by looking at the average box office returns among nominees, rather than just returns for the winner.  This yields the following graph:</p>
<p><a href="http://www.mathgoespop.com/wp-content/uploads/2011/06/Screen-shot-2011-06-09-at-10.49.21-AM.png"><img class="aligncenter size-full wp-image-1272" title="AvgMoney" src="http://www.mathgoespop.com/wp-content/uploads/2011/06/Screen-shot-2011-06-09-at-10.49.21-AM.png" alt="" width="600" height="378" /></a>These numbers aren&#8217;t adjusted for inflation, which may explain in part the growth trend (2009 numbers are bumped up because of <a href="http://www.imdb.com/title/tt0499549/">Avatar</a>, as well).  I&#8217;m less interested in the actual numbers than I am the difference between the two graphs.  And here we see, in contrast to the IMDB case, that the roles of the two awards shows have flipped.  While the average IMDB score of Oscar nominees has always been higher than the average IMDB score of MTV nominees, the average box office return of MTV nominees has always been higher than the average box office return of Oscar nominees.</p>
<p>To return to the original question: do the MTV movie awards highlight more popular films than the Oscars?  Well, it depends on how you define &#8220;popular.&#8221;  If popular means highly rated, the claim is somewhat dubious.  But if popularity is measured by the almighty dollar, then this seems like a fair conclusion to draw.  Whatever your line of thinking, though, I&#8217;m fairly confident that current trends will continue, at least until the last of the Twilight films has exited theaters.</p>
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		<title>Parks and Recreation(al Mathematics)</title>
		<link>http://www.mathgoespop.com/2011/05/parks-and-recreational-mathematics.html</link>
		<comments>http://www.mathgoespop.com/2011/05/parks-and-recreational-mathematics.html#comments</comments>
		<pubDate>Tue, 10 May 2011 18:13:07 +0000</pubDate>
		<dc:creator>Matt</dc:creator>
				<category><![CDATA[Math on TV]]></category>
		<category><![CDATA[charlie sheen]]></category>
		<category><![CDATA[combinatorics]]></category>
		<category><![CDATA[maximum likelihood]]></category>
		<category><![CDATA[parks and recreation]]></category>
		<category><![CDATA[Pigeonhole Principle]]></category>
		<category><![CDATA[probability]]></category>
		<category><![CDATA[the office]]></category>

		<guid isPermaLink="false">http://www.mathgoespop.com/?p=1227</guid>
		<description><![CDATA[<p>Continuing last week&#8217;s trend of discussing mathematics in the context of NBC comedy, today I&#8217;d like to move from The Office to Parks and Recreation.  More specifically, I&#8217;d like to discuss local government wunderkind/aspiring club owner Tom Haverford, whose unique charm I cherish almost as much as Ron Swanson&#8216;s mustache.</p>
<p class="wp-caption-text">What a stud.</p>
<p>In a recent episode, <span style="color:#777"> . . . &#8594; Read More: <a href="http://www.mathgoespop.com/2011/05/parks-and-recreational-mathematics.html">Parks and Recreation(al Mathematics)</a></span>]]></description>
			<content:encoded><![CDATA[<p>Continuing <a href="http://www.mathgoespop.com/2011/05/dunder-math-lin.html">last week&#8217;s</a> trend of discussing mathematics in the context of NBC comedy, today I&#8217;d like to move from <a href="http://en.wikipedia.org/wiki/The_Office_%28U.S._TV_series%29">The Office</a> to <a href="http://en.wikipedia.org/wiki/Parks_and_Recreation">Parks and Recreation</a>.  More specifically, I&#8217;d like to discuss local government wunderkind/aspiring club owner <a href="http://en.wikipedia.org/wiki/Tom_Haverford">Tom Haverford</a>, whose unique charm I cherish almost as much as <a href="http://en.wikipedia.org/wiki/Ron_Swanson">Ron Swanson</a>&#8216;s mustache.</p>
<div id="attachment_1230" class="wp-caption aligncenter" style="width: 434px"><a href="http://www.mathgoespop.com/wp-content/uploads/2011/05/ron-swanson-pic.jpg"><img class="size-full wp-image-1230" title="ron-swanson-pic" src="http://www.mathgoespop.com/wp-content/uploads/2011/05/ron-swanson-pic.jpg" alt="" width="424" height="210" /></a><p class="wp-caption-text">What a stud.</p></div>
<p>In a recent episode, Tom Haverford waxed poetic on the slang he has invented to describe different types of food.  A clip is currently on YouTube (though I don&#8217;t know how long it will stay).</p>
<p style="text-align: center;"><object width="640" height="390"><param name="movie" value="http://www.youtube.com/v/FbR7mpX07Uw?fs=1&amp;hl=en_US" /><param name="allowFullScreen" value="true" /><param name="allowscriptaccess" value="always" /><embed type="application/x-shockwave-flash" width="640" height="390" src="http://www.youtube.com/v/FbR7mpX07Uw?fs=1&amp;hl=en_US" allowscriptaccess="always" allowfullscreen="true"></embed></object></p>
<p style="text-align: left;">Here&#8217;s a list of the slang Tom uses:</p>
<p style="text-align: center;">desserts = &#8216;serts,<br />
entrees = tre-tre&#8217;s,<br />
sandwiches = sammies, sandoozles, or adamsandlers,<br />
cakes = big ole&#8217; cookies,<br />
noodles = long-ass rice,<br />
fried chicken = fry-fry chicky-chick,<br />
chicken parm = chicky-chicky parm-parm,<br />
chicken cacciatore = chicky catch,<br />
eggs = pre-birds or future birds,<br />
root beer = super water,<br />
tortillas = bean blankies.</p>
<p style="text-align: left;">Some folks had the brilliant idea to build on this new parlance by creating a website devoted to related slang that Tom Haverford might use.  The website, <a href="http://tomhaverfoods.com/">tomhaverfoods.com</a>, consists of one of several delightful pictures of Mr. Haverford, followed by a food item and an appropriate slang term.  Click on Tom&#8217;s face and you&#8217;ll get a new term.</p>
<p style="text-align: left;">
<div class="wp-caption aligncenter" style="width: 560px"><a href="http://tomhaverfoods.com/images/tom6.jpg"><img src="http://tomhaverfoods.com/images/tom6.jpg" alt="" width="550" height="368" /></a><p class="wp-caption-text">Watch out, ladies!</p></div>
<p>Here is where the math comes in: the slang items aren&#8217;t numbered, so one can&#8217;t be certain when one has seen all of these inspired terms.  Since the slang terms are (presumably) generated randomly, even if you click on Tom 1,000 times, there is a chance that there will be one slang term that simply hasn&#8217;t appeared.  The issue is further complicated by the fact that the volume of slang terms is surely growing (there is a link on the website for people to submit slang suggestions), but let me ignore this issue for now and simply assume that the website contains a fixed number (say <em>N</em>) slang terms, and when you click on Tom&#8217;s face, one of those slang terms is selected at random to display.</p>
<p style="text-align: left;">Consider the following experiment: go to the website, and record the slang term that awaits you.  Then click on Tom&#8217;s face and record the next slang term.  Repeat this process until you encounter a slang term you&#8217;ve already recorded, and then stop.  This will give you a list of slang terms (say <em>k</em> of them).  The question, then, is the following: can we use <em>k</em> to estimate <em>N</em>?  In other words, can we use the number of unique slang terms we see to estimate how many total slang terms are on the website?</p>
<p style="text-align: left;">We can model this situation with some probability.  Let&#8217;s start with some preliminary analysis.  First, note that if there are <em>N</em> phrases on the website, the worst case is that you will get only one term, and the best case is that you obtain all <em>N</em> (this happens if you are lucky enough to have no repeats until you&#8217;ve seen every possible phrase, so that page view <em>N</em> + 1 must be a repeat, since there are only <em>N</em> total phrases &#8211; this is the <a href="http://en.wikipedia.org/wiki/Pigeonhole_principle">pigeonhole principle</a> at work).</p>
<p style="text-align: left;">Now, you will obtain only one slang term if the second term is the same as the first; since there are <em>N</em> terms total, the probability of the second term being the same as the first term is 1/<em>N</em>.  What about the probability that you obtain two terms?  This happens only if the second term is different from the first, but the third term is one of the previous two.  Since this gives <em>N</em> &#8211; 1 choices for the second page view and 2 for the third, the probability is</p>
<p style="text-align: center;"><img src='http://s.wordpress.com/latex.php?latex=%5Cfrac%7BN-1%7D%7BN%7D%20%5Ccdot%20%5Cfrac%7B2%7D%7BN%7D.&#038;bg=T&#038;fg=000000&#038;s=0' alt='\frac{N-1}{N} \cdot \frac{2}{N}.' title='\frac{N-1}{N} \cdot \frac{2}{N}.' class='latex' /></p>
<p style="text-align: left;">Let&#8217;s generalize this to find the probability that you obtain <em>k</em> terms for some <em>k</em> between 1 and <em>N</em>.  This happens precisely when the first <em>k</em> page views give new terms, but the (<em>k </em>+ 1)st view gives one of the previous <em>k</em> terms.  In order for the first <em>k</em> terms to all be distinct from one another, there are <em>N &#8211; </em>1 choices for the second term, <em>N</em> &#8211; 2 for the third, and so on, so that there are <em>N</em> &#8211; (k &#8211; 1) choices for the <em>k</em>th page view.  Then, since by this point you have seen <em>k</em> terms, this means there are <em>k</em> possible ways for the (<em>k</em> + 1)st view to be a repeat.  Or, mathematically speaking, the probability that the first repeat occurs at the (<em>k</em> + 1)st page view is</p>
<p style="text-align: center;"><img src='http://s.wordpress.com/latex.php?latex=%5Cfrac%7BN-1%7D%7BN%7D%20%5Ccdot%20%5Cfrac%7BN-2%7D%7BN%7D%20%5Ccdot%20%5Cldots%20%5Ccdot%20%5Cfrac%7BN-%28k-1%29%7D%7BN%7D%20%5Ccdot%20%5Cfrac%7Bk%7D%7BN%7D%20%3D%20%5Cfrac%7B%28N-1%29%21%7D%7B%28N-k%29%21%7D%20%5Ccdot%20%5Cfrac%7Bk%7D%7BN%5Ek%7D.&#038;bg=T&#038;fg=000000&#038;s=0' alt='\frac{N-1}{N} \cdot \frac{N-2}{N} \cdot \ldots \cdot \frac{N-(k-1)}{N} \cdot \frac{k}{N} = \frac{(N-1)!}{(N-k)!} \cdot \frac{k}{N^k}.' title='\frac{N-1}{N} \cdot \frac{N-2}{N} \cdot \ldots \cdot \frac{N-(k-1)}{N} \cdot \frac{k}{N} = \frac{(N-1)!}{(N-k)!} \cdot \frac{k}{N^k}.' class='latex' /></p>
<p style="text-align: left;">In other words, if we have a value for <em>k</em>, we can determine what value of <em>N</em> makes this expression as large as possible &#8211; in other words, we can determine the most likely value of <em>N</em>, given <em>k</em>.</p>
<p style="text-align: left;">Let&#8217;s get back to the matter at hand: discovering amazing terms for your favorite foods.  I conducted this experiment, and recorded six unique slang terms; my seventh term was a repeat, so I stopped.  Here is what I recorded:</p>
<p style="text-align: center;">raisins = old ass grapes<br />
hot wings = lil&#8217; flapperz<br />
shrimp = tiny ass lobster<br />
ketchup = kanye blood<br />
mountain dew = halo powerup<br />
gum = chew chew trains</p>
<p>(Sadly, I did not come across one of my personal favorites, funyuns = stank rings.)  Since I found 6 terms, I should take <em>k</em> = 6 in the above expression.  This means I want to choose <em>N</em> so that <img src='http://s.wordpress.com/latex.php?latex=%5Cfrac%7B%28N-1%29%21%7D%7B%28N-6%29%21%7D%20%5Ccdot%20%5Cfrac%7B6%7D%7BN%5E6%7D&#038;bg=T&#038;fg=000000&#038;s=0' alt='\frac{(N-1)!}{(N-6)!} \cdot \frac{6}{N^6}' title='\frac{(N-1)!}{(N-6)!} \cdot \frac{6}{N^6}' class='latex' /> is as large as possible. Let me simply call this expression <em>p</em>(<em>N</em>). By graphing <em>p</em>(<em>N</em>) for varying <em>N</em> (below is the graph for <em>N</em> between 6 and 200), we see that the maximum occurs at 19.  So, based on this data, the best guess as to the number of slang terms on the website is 19.</p>
<p><a href="http://www.mathgoespop.com/wp-content/uploads/2011/05/Picture-24.png"></a><a href="http://www.mathgoespop.com/wp-content/uploads/2011/05/Picture-25.png"><img class="aligncenter size-full wp-image-1239" title="pN6" src="http://www.mathgoespop.com/wp-content/uploads/2011/05/Picture-25.png" alt="" width="600" height="379" /></a><br />
Note that this problem is not unique to this website.  There are plenty of other internet destinations which use this same basic template.  For example, <a href="http://livethesheendream.com/">here</a> is one that will give you Charlie Sheen quotes (if you&#8217;re into that sort of thing).  In this case, I obtained 29 quotes before encountering my first repeat &#8211; this suggests that there are more Charlie Sheen quotes on the internet than Tom Haverford slang (the best estimate for <em>N</em> when <em>k </em>= 29 is, using the same argument as above, is an impressive 425).  This is an imbalance that I hope will be corrected over time.</p>
<p>Of course, in practice one could gather more data before trying to estimate the number of Tom Haverford quotes &#8211; rather than stopping after the first repeat, one could stop after the second, or third, etc.  This, in turn, would change the probability model, so I won&#8217;t get into it here.  I will say, though, that with a little bit more work one can show that the optimal choice of <em>N</em> given <em>k</em> distinct slang terms is the largest whole number such that</p>
<p style="text-align: center;"><img src='http://s.wordpress.com/latex.php?latex=%5Cleft%28%5Cfrac%7BN%7D%7BN-k%7D%20%5Cright%29%20%5Cleft%281-%5Cfrac%7B1%7D%7BN%7D%5Cright%29%5E%7Bk%2B1%7D%20%5Cgeq%201.&#038;bg=T&#038;fg=000000&#038;s=0' alt='\left(\frac{N}{N-k} \right) \left(1-\frac{1}{N}\right)^{k+1} \geq 1.' title='\left(\frac{N}{N-k} \right) \left(1-\frac{1}{N}\right)^{k+1} \geq 1.' class='latex' /></p>
<p style="text-align: left;">This is not exactly the simplest relationship between <em>k</em> and <em>N</em>, which makes a simple formula between the two values hard to come by.  This is unfortunate, but is not such an issue in this case, since you are free to click to your heart&#8217;s content, until you have claimed all the bounty that Tom&#8217;s manner of speech has to offer.</p>
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		<title>Dunder Math-lin</title>
		<link>http://www.mathgoespop.com/2011/05/dunder-math-lin.html</link>
		<comments>http://www.mathgoespop.com/2011/05/dunder-math-lin.html#comments</comments>
		<pubDate>Mon, 02 May 2011 02:55:27 +0000</pubDate>
		<dc:creator>Matt</dc:creator>
				<category><![CDATA[Math on TV]]></category>
		<category><![CDATA[arithmetic]]></category>
		<category><![CDATA[rent]]></category>
		<category><![CDATA[the office]]></category>

		<guid isPermaLink="false">http://www.mathgoespop.com/?p=1203</guid>
		<description><![CDATA[<p>This week, Steve Carell uttered what may well be his last &#8220;That&#8217;s what she said&#8221; as Michael Scott, boss extraordinaire on the US version of The Office.  Though the show will go on, Michael Scott has (spoiler alert) left Pennsylvania for Colorado and the love of his life.  In preparation for this departure, the <span style="color:#777"> . . . &#8594; Read More: <a href="http://www.mathgoespop.com/2011/05/dunder-math-lin.html">Dunder Math-lin</a></span>]]></description>
			<content:encoded><![CDATA[<p>This week, Steve Carell uttered what may well be his last &#8220;That&#8217;s what she said&#8221; as <a href="http://en.wikipedia.org/wiki/Michael_Scott_%28The_Office%29">Michael Scott</a>, boss extraordinaire on the US version of <a href="http://en.wikipedia.org/wiki/The_Office_%28U.S._TV_series%29">The Office</a>.  Though the show will go on, Michael Scott has (spoiler alert) left Pennsylvania for Colorado and the love of his life.  In preparation for this departure, the show has spent the last several episodes easing the audience through the transition.</p>
<p>From a mathematical standpoint, though, there are a couple of inconsistencies. Michael makes no secret of the fact that he has worked for the company for 19 years.  His employees take this loyalty to heart, and in Michael Scott&#8217;s penultimate episode, &#8220;<a href="http://en.wikipedia.org/wiki/Michael%27s_Last_Dundies">Michael&#8217;s Last Dundies</a>,&#8221; they surprise their boss with a song parody of the Rent song &#8220;<a href="http://en.wikipedia.org/wiki/Seasons_of_Love">Seasons of Love</a>,&#8221; which pays homage to such a long period of service.  Below is the relevant clip &#8211; if you don&#8217;t have access to Hulu, you can try <a href="http://www.youtube.com/watch?v=0Musok8lLJ4">this</a> YouTube link, although I imagine it will get pulled eventually.</p>
<p style="text-align: center;"><object width="512" height="288"><param name="movie" value="http://www.hulu.com/embed/NUuleX3ZbAds60KiiPMZMQ" /><param name="allowFullScreen" value="true" /><embed type="application/x-shockwave-flash" width="512" height="288" src="http://www.hulu.com/embed/NUuleX3ZbAds60KiiPMZMQ" allowfullscreen="true"></embed></object></p>
<p>The song begins with a soulful rendition of the following lyrics, courtesy of <a href="http://en.wikipedia.org/wiki/Andy_Bernard">Andy Bernard</a> (Ed Helms):</p>
<blockquote><p>9,986,000 minutes,<br />
We actually sat down, and did the math<br />
9,986,000 minutes,<br />
That&#8217;s how may minutes that you&#8217;ve worked here.</p></blockquote>
<p>Here&#8217;s a question: how does this number compare to Scott&#8217;s claim of 19 years?  Let&#8217;s make a few estimates.</p>
<p>For a crude estimate, we can simply take the length of a year to be 365 days, and count the number of minutes in 19 years given this assumption.  This isn&#8217;t hard; the answer is simply 19 (number of years) x 365 (number of days in a year) x 24 (number of hours in a day) x 60 (number of minutes in an hour) = 9,986,400.  This is exceptionally close to the value cited in the song &#8211; in fact, due to a syllable constraint needed to maintain faithfulness to the original song, it seems likely that this is how the number crunchers in the office actually came up with the value they sang.</p>
<div id="attachment_1213" class="wp-caption aligncenter" style="width: 599px"><a href="http://www.nbc.com/The_Office/photos/andy/4025#item=91774"><img class="size-full wp-image-1213" title="andy" src="http://www.mathgoespop.com/wp-content/uploads/2011/04/andy.png" alt="" width="589" height="390" /></a><p class="wp-caption-text">Andy has the voice of an angel.</p></div>
<p>But how accurate is this number?  This depends on a few factors.  First, if Michael Scott really did begin 19 years ago, this estimate neglects a few leap years.  A better estimate would come from taking 365.25 days in a year, which in turn would give an estimate of 9,993,240 minutes (or 9,993,000 minutes, if one is interested in a number befitting of a Rent song parody).  What&#8217;s more, it&#8217;s unlikely that Michael worked exactly 19 years &#8211; the true length of his stay is probably somewhere between 19 and 20 years, or between 9,993,240 and 10,519,200 minutes.</p>
<p>Depending on your interpretation of the lyrics, though, any of the numbers given above may be much too large.  When Michael&#8217;s employees tell him &#8220;That&#8217;s how many minutes that you&#8217;ve worked here,&#8221; do they mean &#8220;that&#8217;s how many minutes since you&#8217;ve started working here,&#8221; or &#8220;that&#8217;s how many minutes you&#8217;ve spent working since you started working here?&#8221;  If the former, then these estimates seem more or less reasonable.  But if it&#8217;s the latter, we really should only be counting the minutes Scott spent at the office.  If we say that he spent 40 hours a week, roughly, in the office over the past 19 years, then with 365.25/7 weeks per year, this comes out to only 19 x 365.25/7 x 40 x 60, or roughly 2,379,343 minutes, a far cry from our earlier estimates.  To take things even further, based on the evidence provided by the show, the amount of work Michael actually <em>does</em> while in the office seems fairly minimal &#8211; if we&#8217;re talking strictly about the amount of time he&#8217;s spent working in those 19 years, I wouldn&#8217;t be surprised to find a much lower value.  Either way, there seem to be some accounting issues at work here that have been ignored.</p>
<div id="attachment_1214" class="wp-caption aligncenter" style="width: 598px"><a href="http://www.nbc.com/The_Office/photos/photos/423#item=8418"><img class="size-full wp-image-1214" title="accounting" src="http://www.mathgoespop.com/wp-content/uploads/2011/04/accounting.png" alt="" width="588" height="429" /></a><p class="wp-caption-text">Perhaps if accounting spent less time playing solitaire, these issues would have been ironed out.</p></div>
<p>Also, at the risk of sounding like <a href="http://en.wikipedia.org/wiki/Comic_Book_Guy">comic book guy</a>, just two years ago an episode of The Office focused on celebrations for Michael&#8217;s 15th anniversary with Dunder Mifflin; the subsequent cancellation of the festivities by new manager <del>Stringer Bell</del> <a href="http://en.wikipedia.org/wiki/Charles_Miner_%28The_Office%29">Charles Miner</a> drove Michael to quit and start a rival paper company.  One could argue that the time Michael spent not employed by Dunder Mifflin should not count towards his 19 years, but more importantly, 15 + 2 is only 17, not 19.  Before you try to argue that perhaps the show&#8217;s timeline is simply moving faster than the normal rate of one year per year (as TV shows are occasionally wont to do), one needs only to consider the timeline of Jim and Pam&#8217;s baby to see that this is not possible.  So in fact, all of the above discussion is fairly moot &#8211; indeed, we can&#8217;t even be sure how long Michael has worked at Dunder Mifflin.</p>
<p>All is not lost, though.  While we can&#8217;t accurately apply mathematics to this Office-inspired question, others out there have had more success with different questions.  For example, <a href="http://www.cs.washington.edu/homes/brun/pubs/pubs/Kiddon11.pdf">here</a> is a computer science paper on automated recognition of phrases that can reasonably be followed up by the phrase &#8220;that&#8217;s what she said.&#8221;  What a neat problem!  It looks so hard, but they somehow manage to tame it.</p>
<p style="text-align: center;"><object width="512" height="288"><param name="movie" value="http://www.hulu.com/embed/tLIIEwpoG485DCwy469A9A" /><param name="allowFullScreen" value="true" /><embed type="application/x-shockwave-flash" width="512" height="288" src="http://www.hulu.com/embed/tLIIEwpoG485DCwy469A9A" allowfullscreen="true"></embed></object></p>
<p>Oh, Michael Scott.  You will be missed.</p>
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		<title>Do Not Trust the Meat Mathematics Institute</title>
		<link>http://www.mathgoespop.com/2011/03/meatmath.html</link>
		<comments>http://www.mathgoespop.com/2011/03/meatmath.html#comments</comments>
		<pubDate>Wed, 23 Mar 2011 02:43:25 +0000</pubDate>
		<dc:creator>Matt</dc:creator>
				<category><![CDATA[Math and Food]]></category>
		<category><![CDATA[Math on TV]]></category>
		<category><![CDATA[burger king]]></category>
		<category><![CDATA[commercials]]></category>

		<guid isPermaLink="false">http://www.mathgoespop.com/?p=1121</guid>
		<description><![CDATA[<p>Friends, as many of you may have noticed, Burger King has begun a promotion for its BK Stacker line of cheeseburgers.  The ad focuses on Burger King&#8217;s Meat Mathematics Institute, where mathematicians from around the world gather to find ways to bring consumers a maximum amount of meat flavor for a minimum cost.  Sadly, as of <span style="color:#777"> . . . &#8594; Read More: <a href="http://www.mathgoespop.com/2011/03/meatmath.html">Do Not Trust the Meat Mathematics Institute</a></span>]]></description>
			<content:encoded><![CDATA[<p>Friends, as many of you may have noticed, <a href="http://www.bk.com/">Burger King</a> has begun a promotion for its BK Stacker line of cheeseburgers.  The ad focuses on Burger King&#8217;s Meat Mathematics Institute, where mathematicians from around the world gather to find ways to bring consumers a maximum amount of meat flavor for a minimum cost.  Sadly, as of this writing, the ad is not available online, although this related video has made an appearance on YouTube.</p>
<p style="text-align: center;"><iframe title="YouTube video player" width="560" height="349" src="http://www.youtube.com/embed/wilJ0eQoEG8" frameborder="0" allowfullscreen></iframe></p>
<p>While the institute seems like a delightful place to work, I regret to inform you that the research coming out of the institute is as bogus as the existence of the institute itself.  The claimed solution to the problem of maximizing meat (or meat flavor, depending on your source) while minimizing cost is contained in the 3 BK Stackers pictured here (image courtesy of <a href="http://foodbeast.com/content/wp-content/uploads/2011/03/bk-stacker-math.jpg">foodbeast</a>):</p>
<p><a href="http://foodbeast.com/content/wp-content/uploads/2011/03/bk-stacker-math.jpg"><img class="aligncenter" src="http://foodbeast.com/content/wp-content/uploads/2011/03/bk-stacker-math.jpg" alt="" width="600" height="319" /></a>As you can see, the Stacker family of burgers has three members, coming in at price points of $1, $2, and $3, respectively.</p>
<p>Right off the bat you should notice something problematic with their solution.  If the aim is to optimize meat, why are there components that don&#8217;t involve meat?  These components would only add to the cost, without adding to the amount of meat.  You should be able to sell just a single beef patty with some bacon for less than you would be able to sell the $1 stacker, for instance.  Right away, then, we see the corrupt influence that the Burger King sponsorship has had on the otherwise (I&#8217;m sure) irreproachable standard of academic integrity set by the Meat Mathematics Institute.  Without this sponsorship, I&#8217;m sure the mathematicians would&#8217;ve discovered a far more optimal meat-delivery system: the (possibly bacon-wrapped) meatball.</p>
<div id="attachment_1123" class="wp-caption aligncenter" style="width: 510px"><a href="http://www.mathgoespop.com/wp-content/uploads/2011/03/ikea-meatballs.jpg"><img class="size-full wp-image-1123" title="ikea-meatballs" src="http://www.mathgoespop.com/wp-content/uploads/2011/03/ikea-meatballs.jpg" alt="" width="500" height="333" /></a><p class="wp-caption-text">Perhaps the Meat Mathematics Institute should look for a more appropriate sponsor.</p></div>
<p>Even if we restrict our attention to solutions to the &#8220;meat/money&#8221; problem that are in cheeseburger form, however, it&#8217;s still easy to see that the solution proposed by the Meat Mathematics Institute is not correct.  Indeed, a quick stop at the Burger King website reveals the meat differences between the $1, $2, and $3 BK Stackers.  The differences are as follows:</p>
<ul>
<li>$1 Stacker: 1 beef patty, 2 half slices of bacon.</li>
<li>$2 Stacker: 2 beef patties, 3 half slices of bacon.</li>
<li>$3 Stacker: 3 beef patties, 3 half slices of bacon.</li>
</ul>
<p>If we divide out by cost, we easily see that per dollar, these three options give you different amounts of meat!  In particular,</p>
<ul>
<li>$1 Stacker: 1 beef patty, 2 half slices of bacon per dollar</li>
<li>$2 Stacker: 1 beef patty, 1.5 half slices of bacon per dollar</li>
<li>$3 Stacker: 1 beef patty, 1 half slice of bacon.</li>
</ul>
<p>Clearly these three solutions are mathematically inconsistent.  How can the $2 BK Stacker be as optimal a solution as the $1 stacker, when two $1 stackers yield one additional slice of bacon?  Similarly, how can the $3 stacker be as optimal a solution as the $1 stacker, when three $1 stackers yield three additional slices of bacon?  The only way these three solutions can be consistent is if the cost of bacon is 0, which, unfortunately it is not.  But if it were, then the optimal solution still would not be present here, since one could put as much bacon as one wanted on his or her burger without affecting the cost.</p>
<p>It&#8217;s a shame that this institute has been compromised by corporate interests, but this is perhaps not wholly unexpected.  While normally I would advise you to trust your local mathematician, in the case of the meat mathematician, I must regretfully ask you to be on guard.  Especially if he asks you to take him out for a meal.</p>
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		<title>Lost Winnings</title>
		<link>http://www.mathgoespop.com/2011/01/lostwinnings.html</link>
		<comments>http://www.mathgoespop.com/2011/01/lostwinnings.html#comments</comments>
		<pubDate>Thu, 13 Jan 2011 21:45:40 +0000</pubDate>
		<dc:creator>Matt</dc:creator>
				<category><![CDATA[Math in the News]]></category>
		<category><![CDATA[Math on TV]]></category>
		<category><![CDATA[combinations]]></category>
		<category><![CDATA[lost]]></category>
		<category><![CDATA[lottery]]></category>
		<category><![CDATA[probability]]></category>

		<guid isPermaLink="false">http://www.mathgoespop.com/?p=1018</guid>
		<description><![CDATA[<p>Last week, two very lucky people won the Mega Millions lottery jackpot (here&#8216;s a profile on one of the winners).  This particular lottery is played in 41 out of the 50 states, and these two individuals will share a combined, pre-tax total of $380 million.</p>
<p>But are they so lucky after all?  Setting aside the common notion <span style="color:#777"> . . . &#8594; Read More: <a href="http://www.mathgoespop.com/2011/01/lostwinnings.html">Lost Winnings</a></span>]]></description>
			<content:encoded><![CDATA[<p>Last week, two very lucky people won the Mega Millions lottery jackpot (<a href="http://www.megamillions.com/mcenter/pressrelease.asp?newsID=5A051296-4770-4426-A143-535A423640ED">here</a>&#8216;s a profile on one of the winners).  This particular lottery is played in 41 out of the 50 states, and these two individuals will share a combined, pre-tax total of $380 million.</p>
<p>But are they so lucky after all?  Setting aside the common notion that winning the lottery can actually do you more harm than good, some people are concerned because of the numbers themselves that made the winning ticket.</p>
<p>The numbers drawn for this particular lottery were 4, 8, 15, 25, 47, and 42.  Note that the last number is lower than the number that precedes it because it is the so-called &#8220;Mega Number,&#8221; which is drawn from a different pool than the first five.  For those of you with a penchant for televised dramas set in tropical locations, you may note that these numbers bear a striking similarity to Hurley&#8217;s <a href="http://en.wikipedia.org/wiki/Numbers_%28Lost%29">numbers</a> from <a href="http://en.wikipedia.org/wiki/Lost_%28TV_series%29">Lost</a>.</p>
<p><a href="http://www.tv.com/hurleys-numbers-arent-so-unlucky-anymore/webnews/249677.html"><img class="aligncenter size-full wp-image-1023" title="hurnums" src="http://www.mathgoespop.com/wp-content/uploads/2011/01/hurnums.jpg" alt="" width="480" height="401" /></a></p>
<p>As evidenced by the above image, Hurley&#8217;s number&#8217;s were 4, 8, 15, 16, 23, and 42.  In other words, 4 out of the 6 Mega Millions numbers matched Hurley&#8217;s!</p>
<p>Unfortunately, Lost fans will note that this is not necessarily a good thing; on the show, the numbers caused Hurley nothing but trouble (including, but not limited to, a meteor strike on his place of work).  Hurley (real name <a href="http://www.imdb.com/name/nm0306201/">Jorge Garcia</a>) himself wrote on his <a href="http://furtherdispatches.wordpress.com/2011/01/05/will-you-people-ever-learn/">blog</a>: &#8220;When will you people learn? The numbers are bad!&#8221;</p>
<div id="attachment_1027" class="wp-caption aligncenter" style="width: 404px"><a href="http://www.mathgoespop.com/wp-content/uploads/2011/01/hurley.jpg"><img class="size-full wp-image-1027" title="hurley" src="http://www.mathgoespop.com/wp-content/uploads/2011/01/hurley.jpg" alt="" width="394" height="222" /></a><p class="wp-caption-text">This is how Hurley feels about the numbers.</p></div>
<p>From a mathematical standpoint, though, I&#8217;m less interested in whether or not the numbers are cursed (if the show is any indication, this question has already been decisively settled), and more interested in how likely it is for the lottery jackpot to so closely match the numbers from the show.</p>
<p>Lottery odds are quite well understood.  What&#8217;s more, someone by the name of Durango Bill has a <a href="http://www.durangobill.com/MegaMillionsOdds.html">website</a> devoted to odds for the Mega Millions lottery (he also calculates that the odds of dying in a car accident on the way to buy a lottery ticket are almost 6 times as high as the odds of winning the lottery itself).  We don&#8217;t need all the information on this site, though, just some of it.</p>
<p>To calculate the odds, one needs to know how many numbers are in play for the lottery.  The first five numbers are drawn from a pool (without replacement) of 56, while the Mega Number is drawn from a pool of 46.  Since we are choosing 5 numbers from the original 56, the total number of outcomes is 56 <a href="http://en.wikipedia.org/wiki/Combination">choose</a> 5, or 3,819,816.  Clearly there are 46 different choices for the Mega Number.  Therefore, the total number of outcomes is the product 3,819,816 x 46 = 175,711,536.</p>
<p>(As an aside, note that this is much higher than the number of outcomes available if the Mega Number didn&#8217;t exist, and one simply chose 6 numbers from the pool of 56.  In this case, the number of outcomes would be 56 choose 6, or 32,468,436.  In other words, use of the Mega Number effectively makes the number of outcomes over 5 times larger, thereby significantly decreasing the likelihood of a jackpot!)</p>
<p>Now, what are the odds that three of the five numbers, in addition to the Mega Number, will match the Lost numbers?  Well, there&#8217;s only one way to match the Mega Number, but there are 5 choose 3 = 10 ways to match 3 of the 5 Lost numbers, and 51 choose 2 = 1,275  ways to match 2 of the 51 non-lost numbers.  Therefore, the total number of favorable outcomes is 1,275 x 10 = 12,750, which means the probability of this event occurring must be 12,750/175,711,536 (the proportion of total outcomes which are favorable), which amounts to around 1 in 13,781. In particular, this is 12,750 times as likely as winning the jackpot, for which the odds are 1/175,711,536.</p>
<p>&#8220;But wait!&#8221; you might say.  &#8220;Not only did the numbers match, but their positions matched too!&#8221;  In other words, the 4, 8, and 15 were the first three numbers in both lotteries.  If we take position into account, we could ask &#8220;What are the odds that 3 of the 5 numbers and the Mega Number match the Lost Numbers, and have the same position?&#8221;  You should expect that these odds are lower, since we are now further restricting the types of tickets that we count (for example, the ticket 1 2 4 8 15 42 would count only if position doesn&#8217;t matter).</p>
<p>If we fix the positions, then we want to count the number of possible lottery tickets of the form 4 8 15 <em>a b</em> 42, where <em>a</em> must be between 17 and <em>b</em> (since the numbers are listed in increasing order and 16 is not allowed), not including 23, and <em>b</em> must be between <em>a</em> and 56, not including 23.</p>
<p>To count these outcomes, we split into two cases.  First, if <em>a </em>is between 17 and is less than 23, then there are 6 choices for <em>a</em> (17, 18, 19, 20, 21, or 22) and for each choice of <em>a</em> there are 56 &#8211; <em>a</em> &#8211; 1 = 55 &#8211; <em>a</em> choices for <em>b</em> (since <em>b</em> must lie between <em>a</em> + 1 and 56, and can&#8217;t be 23).  Therefore, the total number of outcomes if <em>a</em> is less than 23 is</p>
<p style="text-align: center;"><img src='http://s.wordpress.com/latex.php?latex=%5Csum_%7Ba%3D17%7D%5E%7B22%7D%2855-a%29%20%3D%20213.&#038;bg=T&#038;fg=000000&#038;s=0' alt='\sum_{a=17}^{22}(55-a) = 213.' title='\sum_{a=17}^{22}(55-a) = 213.' class='latex' /></p>
<p style="text-align: left;">Secondly, if <em>a</em> is greater than 23, then there are 32 choices for <em>a </em>(since <em>a</em> must lie between 24 and 55), and for each choice of <em>a</em> there are now 56 &#8211; <em>a</em> choices for <em>b</em>.  In particular, note that <em>a</em> can never be 56, since <em>a</em> must be less than <em>b</em>, and 56 is the highest possible number. Therefore, in this case, the number of outcomes is</p>
<p style="text-align: center;"><img src='http://s.wordpress.com/latex.php?latex=%5Csum_%7Ba%3D24%7D%5E%7B55%7D%2856-a%29%20%3D%20528.&#038;bg=T&#038;fg=000000&#038;s=0' alt='\sum_{a=24}^{55}(56-a) = 528.' title='\sum_{a=24}^{55}(56-a) = 528.' class='latex' /></p>
<p style="text-align: left;">From this, we see the number of favorable outcomes is now only 213 + 528 = 741, which makes the probability of a jackpot with 4 of 6 numbers (including the Mega Number) in the same position as 4 of the 6 Lost Numbers only 741/175,711,536, or roughly 1 in 237,128.  In particular, the odds are decreased by a factor of over 17.</p>
<p style="text-align: left;">To put it more succinctly, the odds are small.  But when the lottery is involved, one frequently encounters unlikely events such as this.  While it&#8217;s a cool coincidence, I think we can all agree it&#8217;s unwise to play the Lost Numbers when you buy your lottery tickets.  It just doesn&#8217;t make sense to choose the most popular possible combination of numbers &#8211; after all, you don&#8217;t want to share that Jackpot with anyone.</p>
<p style="text-align: left;">Just as importantly, of course, nobody wants to bet with cursed numbers.</p>
<p style="text-align: left;">(Other articles can be found <a href="http://latimesblogs.latimes.com/showtracker/2011/01/thank-you-hurley-lost-numbers-pay-off-as-winning-mega-millions-numbers.html">here</a> and <a href="http://latimesblogs.latimes.com/showtracker/2011/01/jorge-garcia-and-carlton-cuse-respond-to-mega-millions-winning-lost-numbers.html">here</a>.)</p>
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		<title>Putting the &#8220;e&#8221; in &#8220;The Simpsons&#8221;</title>
		<link>http://www.mathgoespop.com/2010/12/putting-the-e-in-the-simpsons.html</link>
		<comments>http://www.mathgoespop.com/2010/12/putting-the-e-in-the-simpsons.html#comments</comments>
		<pubDate>Thu, 23 Dec 2010 03:57:19 +0000</pubDate>
		<dc:creator>Matt</dc:creator>
				<category><![CDATA[Math on TV]]></category>
		<category><![CDATA[e]]></category>
		<category><![CDATA[sesame street]]></category>
		<category><![CDATA[the simpsons]]></category>

		<guid isPermaLink="false">http://www.mathgoespop.com/?p=993</guid>
		<description><![CDATA[<p style="text-align: left;">I think we can safely agree that The Simpsons isn&#8217;t the show that it used to be, but there are moments when its former charm shines through.  As it pertains to the material of this blog, I was particularly pleased with a joke that ran on their Christmas episode.  I have been meaning to <span style="color:#777"> . . . &#8594; Read More: <a href="http://www.mathgoespop.com/2010/12/putting-the-e-in-the-simpsons.html">Putting the &#8220;e&#8221; in &#8220;The Simpsons&#8221;</a></span>]]></description>
			<content:encoded><![CDATA[<p style="text-align: left;">I think we can safely agree that <a href="http://en.wikipedia.org/wiki/The_Simpsons">The Simpsons</a> isn&#8217;t the show that it used to be, but there are moments when its former charm shines through.  As it pertains to the material of this blog, I was particularly pleased with a joke that ran on their Christmas episode.  I have been meaning to tip my hat to this joke for some time, but it has been hard to find a spare moment to do so.</p>
<p style="text-align: left;">The joke ran at the end of a muppet-themed segment of the show.  In an homage to <a href="http://en.wikipedia.org/wiki/Sesame_Street">Sesame Street</a>, after the segment finished (but before the somewhat racy <a href="http://www.nydailynews.com/entertainment/tv/2010/12/06/2010-12-06_katy_perrys_simpsons_guest_appearance_takes_multiple_jabs_at_sesame_street_elmo_.html">joke</a> involving a very physical muppet Moe) an announcer stopped to give thanks to the sponsors of the show.  Unlike Sesame Street, however, which is sponsored every day by two letters and a number, this episode of The Simpsons was sponsored by one symbol and one number that looks like a letter:</p>
<p style="text-align: center;"><object classid="clsid:d27cdb6e-ae6d-11cf-96b8-444553540000" width="512" height="288" codebase="http://download.macromedia.com/pub/shockwave/cabs/flash/swflash.cab#version=6,0,40,0"><param name="allowFullScreen" value="true" /><param name="src" value="http://www.hulu.com/embed/VZoD1vhnH-Jv28kx-enKgg/1254/1264" /><param name="allowfullscreen" value="true" /><embed type="application/x-shockwave-flash" width="512" height="288" src="http://www.hulu.com/embed/VZoD1vhnH-Jv28kx-enKgg/1254/1264" allowfullscreen="true"></embed></object></p>
<p style="text-align: left;">In case you&#8217;re late to the party (since I don&#8217;t think that clip will be online forever), let me quote: &#8220;Tonight&#8217;s Simpsons episode was brought to you by the symbol umlaut, and the number <a href="http://en.wikipedia.org/wiki/E_(mathematical_constant)">e</a>.  Not the letter e, but the number, whose exponential function is the <a href="http://en.wikipedia.org/wiki/Derivative">derivative</a> of itself.&#8221;</p>
<p style="text-align: left;">Kudos to the writers for incorporating some choice math humor into the tail end of this episode (I&#8217;m willing to overlook some qualms with their wording).  Perhaps Simpsons aficianados would can begin preparations for next year&#8217;s <a href="http://www.mathgoespop.com/2010/01/e-day.html">e day</a>.</p>
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		<title>Pi, I Shake My Fist at You</title>
		<link>http://www.mathgoespop.com/2010/11/pi-i-shake-my-fist-at-you.html</link>
		<comments>http://www.mathgoespop.com/2010/11/pi-i-shake-my-fist-at-you.html#comments</comments>
		<pubDate>Wed, 24 Nov 2010 22:02:33 +0000</pubDate>
		<dc:creator>Matt</dc:creator>
				<category><![CDATA[Math Education]]></category>
		<category><![CDATA[Math in the News]]></category>
		<category><![CDATA[Math on TV]]></category>
		<category><![CDATA[pi]]></category>

		<guid isPermaLink="false">http://www.mathgoespop.com/?p=953</guid>
		<description><![CDATA[<p>A couple of days ago I watched a video that really depressed me.  Here&#8216;s a link to a local news story from Ankeny, Iowa &#8211; I&#8217;d encourage you to take a look at the news clip there (unfortunately, I can&#8217;t embed it here).  The story concerns a 6th grade student who has memorized the decimal expansion <span style="color:#777"> . . . &#8594; Read More: <a href="http://www.mathgoespop.com/2010/11/pi-i-shake-my-fist-at-you.html">Pi, I Shake My Fist at You</a></span>]]></description>
			<content:encoded><![CDATA[<p>A couple of days ago I watched a video that really depressed me.  <a href="http://www.kcci.com/r/25845894/detail.html">Here</a>&#8216;s a link to a local news story from Ankeny, Iowa &#8211; I&#8217;d encourage you to take a look at the news clip there (unfortunately, I can&#8217;t embed it here).  The story concerns a 6th grade student who has memorized the decimal expansion of pi to 340 or so digits.</p>
<p>In and of itself, this might not seem like a particularly newsworthy achievement &#8211; as any <a href="http://en.wikipedia.org/wiki/Pi_Day">Pi Day</a> aficionado can tell you, there are people who have memorized more digits.  Perhaps what makes it newsworthy is the fact that the student is only twelve years old, or, more perversely, the fact that his accomplishment came in response to the challenge of his math teacher, who asked his students to memorize as many digits of pi as possible.  By far the most depressing part of the video is a brief clip that shows all the students in the classroom mindlessly rattling off successive digits of pi.  The lack of enthusiasm is almost palpable.</p>
<p>Now, I don&#8217;t want to come off as too much of a curmudgeon here.  I have no doubt that this student is stoked that he made it on to TV for an academic achievement, regardless of the actual merits of that achievement (at least the student is aware enough to remark that the information he&#8217;s memorized will probably never be put to use).  That&#8217;s fine &#8211; he has every right to be proud of himself for making it onto the local news.  What really gets my goat is the fact that this teacher thought it would be a good idea to make students memorize digits of pi.  I can think of few better ways to dampen a natural enthusiasm for mathematical learning than by asking students to memorize a series of digits that will have no practical value for any of them, ever.  It would be like having an English teacher ask students to memorize a random string of words which, taken collectively, didn&#8217;t teach the student anything about vocabulary or grammar.</p>
<p>Is there any benefit to this exercise?  According to the teacher, &#8220;The ability to memorize that much stuff has to help tremendously.&#8221;  Well, ok.  But aren&#8217;t there more important things to learn about in math class?  Is math class really the best venue to discover a talent like this?  I am fairly certain that students in Singapore aren&#8217;t spending class time and homework time memorizing digits of pi.  I&#8217;m sure this teacher has good intentions, but I fail to see much value in this apparently newsworthy event.  The mystique of the number pi, I suppose, never fails to attract attention.</p>
<p>If this exercise is what gets this sixth grader interested in math, then by all means he should memorize as many digits of pi as he can.  For the vast majority of students, however, such an exercise is probably beyond tedious.  I can only hope that this news story doesn&#8217;t inspire other teachers to compel other students to do the same thing.</p>
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