Varadhan, New York University, for his work in probability theory, especially his work on large deviations from expected random behavior which has revolutionized this field of study during the second half of the 20th century, and become a cornerstone of both pure and applied probability.

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The two researchers did some calculations--this field requires a black belt in statistics--and discovered that the probability that two people might have identical lists of movies with the same ratings is tiny.

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