# Normal and Log-Normal Probability Density Functions with Identical Mean and Standard Deviation

Normal and Log-Normal Probability Density Functions with Identical Mean and Standard Deviation

This Demonstration compares a log-normal distribution probability density function (PDF) with parameters and with a normal distribution PDF with parameters and . Both PDFs have identical mean and standard deviation. Since the log-normal distribution is defined for positive values, it is not possible to have an equivalent normal distribution with negative mean.

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