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Given this contingency table, WordHoard calculates the log-likelihood ratio statistic G2 to assessThe log-likelihood ratio measures the discrepancy of the the observed word frequencies from the valuesSimply put, the log-likelihood value tells us how much more likely
来最小化函数poissonNegLogLikelihood,该函数的定义如下: def poissonNegLogLikelihood(lam, y):
Computes the negative log-likelihoodThe negative log-likelihood for the data (y) with parameter (lam).