Complex sentence: Historically, the third and fourth standardized moments (skewness and kurtosis) were some of the earliest tests for normality; other early test statistics include the ratio of the mean absolute deviation to the standard deviation and of the range to the standard deviation.
Split into simpler sentences: Historically, the third and fourth standardized moments (skewness and kurtosis) were some of the earliest tests for normality. Other early test statistics include the ratio of the mean absolute deviation to the standard deviation and of the range to the standard deviation.