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# Monthly Archives: April 2013

## Taking balls away: Oz’ Version

This post is based on a comment by Oz to our question about balls with two colors: “There is an interesting (and more difficult) variation I once heard but can’t recall where: You have a box with n red balls … Continue reading

Posted in Guest post, Probability, Test your intuition
Tagged Oz, Probability, Test your intuition
14 Comments

## Answer to test your intuition (18)

You have a box with n red balls and n blue balls. You take out balls one by one at random until left only with balls of the same color. How many balls will be left (as a function of n)? … Continue reading

Posted in Probability, Test your intuition
Tagged Itai Benjamini, Probability, random permutation, Ronen Eldan, Test your intuition
3 Comments

## Itai Ashlagi, Yashodhan Kanoria, and Jacob Leshno: What a Difference an Additional Man makes?

We are considering the stable marriage theorem. Suppose that there are n men and n women. If the preferences are random and men are proposing, what is the likely average women’s rank of their husbands, and what is the likely average … Continue reading

## Andrei

Andrei Zelevinsky passed away a week ago on April 10, 2013, shortly after turning sixty. Andrei was a great mathematician and a great person. I first met him in a combinatorics conference in Stockholm 1989. This was the first major … Continue reading

## The Mystery Piano-Player at the Mittag-Leffler Institute

In a previous post I told you about my Mittag-Leffler 2005 experience, and challenged you, readers, to discover the identity of a mysterious piano player. Coming from Yale, I was jet-lagged, an experience which already worked for me once in 1991 … Continue reading

## QSTART

Physics, Computer Science, Mathematics, and Foundations’ views on quantum information Inauguration conference for the Quantum Information Science Center (QISC), Hebrew university of Jerusalem Update: The news of our conference have made it to a big-league blog. Update (July 2013): QStart … Continue reading

## Test Your Intuition (19): The Advantage of the Proposers in the Stable Matching Algorithm

Stable mariage The Gale-Shapley stable matching theorem and the algorithm. GALE-SHAPLEY THEOREM Consider a society of n men and n women and suppose that every man [and every woman] have a preference (linear) relation on the women [men] he [she] knows. Then … Continue reading

## Test Your Intuition (18): How many balls will be left when only one color remains?

(Thanks to Itai Benjamini and Ronen Eldan.) Test (quickly) your intuition: You have a box with n red balls and n blue balls. You take out balls one by one at random until left only with balls of the same … Continue reading

Posted in Probability, Test your intuition
25 Comments