# AnalyticBridge

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# Math and Computer Science Problems

## Information

Challenging problems, brain teasers, just for fun.

Members: 37
Latest Activity: Sep 30, 2012

## Discussion Forum

If you empty a bathtub one yard north of the equator, the whirlpool is spinning clockwise. One yard south of the equator, it is spinning anti-clockwise. There's even a tourist attraction in Kenya…Continue

Started by Vincent Granville. Last reply by Amanda Shankle-Knowlton Jul 18, 2011.

### Interesting combinatorial problem

Let t(n) be the number of subsets of {1,2,...,n} such that, when the elements of the subset are listed in increasing order, the first is odd, the second is even, the third is odd and so forth. We…Continue

Started by Vincent Granville Jun 25, 2011.

### Probability question regarding nuclear accidents1 Reply

Based on density and spatial location of nuclear plants on Earth, what is the probability of a 1-ton asteroid (just big enough to create an impact crater) to hit any place on earth less than 50 miles…Continue

Started by Amy. Last reply by Vincent Granville Apr 17, 2011.

### ACM PDS on HTML5 on May 15

An Introduction to HTML5 on May 14Professional Development SeminarPresented…Continue

Started by Vera Klimkovsky Apr 10, 2011.

### Prime number theorem

FrameworkI came up with a very simple function to generate all prime numbers, but I'm not sure it is of any use: h(x) = Product{ f(x-kl) }, where the product is taken over all integers k, l greater…Continue

Started by Vincent Granville Feb 26, 2011.

### What is the maximum return a trader can consistently make, in a 12 month time period, without being sued?1 Reply

Let's assume that we have N traders, trading randomly using market-neutral strategies (or trading randomly in a neutral market, as the one we have now).Each day, each trader re-invests all her gains.…Continue

Started by Vincent Granville. Last reply by Ralph Winters Nov 30, 2010.

### Text mining computer science problem (computational complexity)

You have to compute a list of multi-token keywords that contain specific one-token keywords such as car, insurance, degree, etc. You have a 10MM multi-token keyword list, and a 5,000 list of…Continue

Started by Vincent Granville Jul 20, 2010.

### A question for physicists2 Replies

Assuming that the Universe is compact and expanding at a constant rate in all directions, and using a model of the Universe that seems reasonable:1) Can we measure the minimum speed v at which a…Continue

Started by Mirko Krivanek. Last reply by Vincent Granville Jun 13, 2010.

### Testing if a distribution is bimodal

A data set comes from a mixture of 2 independent one-dimensional normal distributions with same variance. How do we test whether both means are identical? What about using the average distance D…Continue

Started by Vincent Granville May 12, 2010.

In a contest, 20 participants are asked to sample 12 wines: 6 wines are in the \$15-25/bottle price range, and 6 ones are in the \$80-150/bottle price range. For each of the 12 wines, participants are…Continue

Started by Vincent Granville. Last reply by Vincent Granville Mar 11, 2010.

## Comment Wall

Comment

Comment by Steffen Springer on February 11, 2010 at 1:02pm
Found recently: http://projecteuler.net/

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