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 Call for nominations for the Ostrowski Prize 2017
 Problems for Imre Bárány’s Birthday!
 Twelves short videos about members of the Department of Mathematics and Statistics at the University of Victoria
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 Around the GarsiaStanley’s Partitioning Conjecture
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 Analysis of Boolean Functions
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 'Gina Says'
 Answer: Lord Kelvin, The Age of the Earth, and the Age of the Sun
 Sarkaria's Proof of Tverberg's Theorem 2
 A Breakthrough by Maryna Viazovska Leading to the Long Awaited Solutions for the Densest Packing Problem in Dimensions 8 and 24
 Jim Geelen, Bert Gerards, and Geoﬀ Whittle Solved Rota's Conjecture on Matroids
 Polymath 10 Emergency Post 5: The ErdosSzemeredi Sunflower Conjecture is Now Proven.
 Sarkaria's Proof of Tverberg's Theorem 1
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Category Archives: Test your intuition
Oz’ Balls Problem: The Solution
A commentator named Oz proposed the following question: You have a box with n red balls and n blue balls. You take out each time a ball at random but, if the ball was red, you put it back in the box and take out … Continue reading
Posted in Probability, Test your intuition
Tagged Erosion, J. F. C. Kingman, Probability, S. E. Volkov
1 Comment
Answer: Lord Kelvin, The Age of the Earth, and the Age of the Sun
Yeshu Kolodni and Lord Kelvin The question In 1862, the physicist William Thomson (who later became Lord Kelvin) of Glasgow published calculations that fixed the age of Earth at between 20 million and 400 … Continue reading
Posted in Geology, Physics, 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
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
Test Your Intuition (19): The Advantage of the Proposers in the Stable Matching Algorithm
Stable mariage The GaleShapley stable matching theorem and the algorithm. GALESHAPLEY 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
26 Comments
Test Your Intuition (17): What does it Take to Win TicTacToe
(A few more quantum posts are coming. But let’s have a quick break for games.) Tic Tac Toe is played since anciant times. For the common version, where the two players X and O take turns in marking the empty squares … Continue reading