Sandbox: Difference between revisions

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==March bracket madness==
The last installment of Chance News, [http://test.causeweb.org/wiki/chance/index.php/Chance_News_97#Warren_Buffett.27s_billion_dollar_gamble Warren Buffett's challenge] on the NCAA basketball tournament.


We received the following news updates from Jim Greenwood and Margaret Cibes
==Big data surprises==
[http://online.wsj.com/news/articles/SB10001424052702303369904579423132072969654 Big data uncovers some weird correlations]<br>
by By Deborah Gage , ''Wall Street Journal'', 23 March 2014


*[http://www.nytimes.com/2014/03/16/sports/ncaabasketball/mathematicians-are-hoping-their-calculations-add-up-to-the-perfect-bracket.html Mathematicians are hoping their calculations add up to the perfect bracket], by Mary Pilon, ''New York Times'', 15 March 2014
The article is subtitled "There's a Link Between Sales and Phases of the Moon, Among Other Things."  It includes the following graphic, which could qualify as a Forsooth!


* [http://www.nytimes.com/2014/03/25/sports/ncaabasketball/in-ncaa-tournament-bracket-mathematician-outdoes-matildas.html?hpw&rref=sports In N.C.A.A. tournament bracket, mathematician outdoes Matildas], by Joe Drape, ''New York Times'', 24 March 2014
<center>[[File:MoonMetrics.jpg | 400px]]</center>


These articles describe efforts by aDavidson College math professor, Tim Chartier, who used an algorithm based on applied linear algebra to make bracket predictions.
Here is another example:
 
==A pair of probability puzzles==
[A coin problem]
<blockquote>
<blockquote>
Consider this simple game: flip a fair coin twice. You win if you get two heads, and lose otherwise. It’s not hard to calculate that the chances of winning are 1/4.
The online lender ZestFinance Inc. found that people who fill out their loan applications using all capital letters default more often than people who use all lowercase letters, and more often still than people who use uppercase and lowercase letters correctly.
<br><br>
<br><br>
Your challenge is to design a game, using only a fair coin, that you have a 1/3 chance of winning.
ZestFinance Chief Executive Douglas Merrill says the company looks at tens of thousands of signals when making a loan, and it doesn't consider the capital-letter factor as significant as some other factors—such as income when linked with expenses and the local cost of living.
</blockquote>
Continues "And here is my recipe for getting the most out of this problem: if you can solve it, do not stop with one answer. Rather, see how many answers you can come up with. I’ve posed this problem to many people, and I continue to hear novel solutions."
 
[http://wordplay.blogs.nytimes.com/2014/03/24/urn/ A large urn]<br>
by Gary Antonik, Numberplay blog, ''New York Times'', 24 March 2014
 
<blockquote>
There are 600 black marbles and 400 white marbles mixed well in a large urn. You draw marbles one by one at random without replacement until you take out all the marbles of one of the colors. What is the probability that at least one white marble will be left in the urn?
<br><br>
<br><br>
Bonus: On average, how many marbles will be left in the urn?
So while it may take capital letters into consideration when evaluating an application, it hasn't held a loan up because of it.
</blockquote>
</blockquote>


Submitted by Bill Peterson
Submitted by Paul Alper

Revision as of 00:03, 21 April 2014

Big data surprises

Big data uncovers some weird correlations
by By Deborah Gage , Wall Street Journal, 23 March 2014

The article is subtitled "There's a Link Between Sales and Phases of the Moon, Among Other Things." It includes the following graphic, which could qualify as a Forsooth!

MoonMetrics.jpg

Here is another example:

The online lender ZestFinance Inc. found that people who fill out their loan applications using all capital letters default more often than people who use all lowercase letters, and more often still than people who use uppercase and lowercase letters correctly.

ZestFinance Chief Executive Douglas Merrill says the company looks at tens of thousands of signals when making a loan, and it doesn't consider the capital-letter factor as significant as some other factors—such as income when linked with expenses and the local cost of living.

So while it may take capital letters into consideration when evaluating an application, it hasn't held a loan up because of it.

Submitted by Paul Alper

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