Kurtosis (from the Greek word κυρτός, kyrtos or kurtos, meaning bulging) is a measure of the "tailedness" of the distribution of sample data. Positive kurtosis (leptokurtic) indicates a distribution more outlier-prone than predicted by a normal distribution, and negative kurtosis (platykurtic) indicates a distribution less outlier-prone than a normal distribution. 0 would indicate that the outlier-producing potential is similar to that of a normal distribution.

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