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Statistics::ChiSquare - How well-distributed is your data? SYNOPSIS use Statistics::Chisquare; print chisquare(@array_of_numbers); Statistics::ChiSquare is available at a CPAN site near you. Suppose you flip a coin 100 times, and it turns up heads 70 times. Is the coin fair? Suppose you roll a die 100 times, and it shows 30 sixes. Is the die loaded? In statistics, the chi-square test calculates how well a series of numbers fits a distribution. In this module, we only test for whether results fit an even distribution. It doesnt simply say "yes" or "no". Instead, it gives you a confidence interval, which sets upper and lower bounds on the likelihood that the variation in your data is due to chance. See the examples below. If youve ever studied elementary genetics, youve probably heard about Georg Mendel. He was a wacky Austrian botanist who discovered (in 1865) that traits could be inherited in a predictable fashion. He did lots of experiments with cross breeding peas: green peas, yellow peas, smooth peas, wrinkled peas. A veritable Brave New World of legumes. But Mendel faked his data. A statistician by the name of R. A. Fisher used the chi-square test to prove it. Theres just one function in this module: chisquare(). Instead of returning the bounds on the confidence interval in a tidy little two-element array, it returns an English string. This was a deliberate design choice---many people misinterpret chi-square results, and the string helps clarify the meaning. The string returned by chisquare() will always match one of these patterns: "Theres a >d+% chance, and a.
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Windows Software
Albina Merfyn - I find this to be really easy to use. I can...
