Student Puzzle Corner
Bulletin Editor Anirban DasGupta writes the solution to the previous puzzle. The exact problem was this: Fix $\epsilon 0$. Give examples of two absolutely continuous distributions with densities $f$ and $g$ such that $|f(x)-g(x)| \leq \epsilon $ for all $x$, and one of the two distributions is infinitely divisible…

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The deadline for the Student Puzzle printed in the last issue is October 20, 2015, so there is still time to enter! The puzzle appears at https://imstat.org/2015/08/student-puzzle-corner-11/. We await your submission!…

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Infinite divisibility of Euclidean random variables and vectors has been a core theme in the theory of probability for at least sixty years. The question asked is when can a random variable be decomposed into small independent components. Precisely, a random variable (vector) $X$ is called infinitely divisible if for…

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Bulletin Editor Anirban DasGupta writes: The problem asked was to settle the possibility of consistent estimation with incomplete data in three examples, and to provide a concrete one when consistent estimation is possible. Intuitively, in case (a), you can only infer about $|\mu |$, but not the sign of $\mu…

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In this issue, we look at the consequences of having only incomplete data. For example, suppose a random variable $X$ has a normal distribution with mean $\mu $ and variance $\sigma ^2$, and both parameters need to be estimated. With usual data, which we call complete data, namely iid copies…

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