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 Proof By Lice!
 The seventeen camels riddle, and Noga Alon’s camel proof and algorithms
 Edmund Landau and the Early Days of the Hebrew University of Jerusalem
 Boolean Functions: Influence, Threshold, and Noise
 Laci Babai Visits Israel!
 Polymath10 conclusion
 Is HeadsUp Poker in P?
 The Median Game
 International mathematics graduate studies at the Hebrew University of Jerusalem
Top Posts & Pages
 The seventeen camels riddle, and Noga Alon's camel proof and algorithms
 Answer: Lord Kelvin, The Age of the Earth, and the Age of the Sun
 Proof By Lice!
 A Breakthrough by Maryna Viazovska Leading to the Long Awaited Solutions for the Densest Packing Problem in Dimensions 8 and 24
 Updates and plans III.
 Extremal Combinatorics III: Some Basic Theorems
 Polymath10: The Erdos Rado Delta System Conjecture
 Mind Boggling: Following the work of Croot, Lev, and Pach, Jordan Ellenberg settled the cap set problem!
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Tag Archives: Test your intuition
TYI 26: Attaining the Maximum
(Thanks, Dani!) Given a random sequence , ******, , let . and assume that . What is the probability that the maximum value of is attained only for a single value of ? Test your intuition: is this probability bounded … Continue reading
TYI 25: The Automorphism Group of the Symmetric Group
True or False: The group of automorphisms of the symmetric group , n ≥ 3 is itself.
Posted in Algebra and Number Theory, Test your intuition
Tagged Test your intuition, the symmetric group
7 Comments
Test your intuition 24: Which of the following three groups is trivial
Martin Bridson We have three finitely presented groups A is generated by two generators a and b and one relation B is generated by three generators a, b, c and three relations , . C is generated by four generators a, b, c, d … Continue reading
Posted in Algebra and Number Theory, Test your intuition
Tagged Martin Bridson, Test your intuition
10 Comments
Test Your Intuition (23): How Many Women?
How many women can you find on this poster announcing the 25th Jerusalem School in Economics Theory devoted to Matching and Market Design? Please respond to the poll:
Answer to Test Your Intuition (22)
Indeed, most people got it right! Bundling sometimes increases revenues, sometimes keeps revenues the same, and sometimes decreases revenues. In fact, this is an interesting issue which was the subject of recent research effort. So here are a few … Continue reading
Posted in Economics, Test your intuition
Tagged Auctions, Noam Nisan, Sergiu Hart, Test your intuition
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Test your intuition (22): Selling Two Items in a Bundle.
One item You have one item to sell and you need to post a price for it. There is a single potential buyer and the value of the item for the buyer is distributed according to a known probability distribution. It … Continue reading
Test Your Intuition (21): Auctions
You run a singleitem sealed bid auction where you sell an old camera. There are three bidders and the value of the camera for each of them is described by a certain (known) random variable: With probability 0.9 the value … Continue reading
Posted in Economics, Games, Test your intuition
Tagged Auctions, Roger Myerson, Test your intuition
4 Comments
Test your Intuition/Knowledge: What was Lord Kelvin’s Main Mistake?
The age of the earth (Thanks to Yeshu Kolodny) We now know that the age of the earth is 4.54±1% Billion years. From Wikipedea: In 1862, the physicist William Thomson (who later became Lord Kelvin) of Glasgow published calculations that … Continue reading
Posted in Controversies and debates, Geology, Physics, Test your intuition
Tagged Earth, Geology, Lord Kelvin, Test your intuition
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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