Review of Descriptive Statistics

	Statistic	Sample	Population
Measures of Central Tendency	Mean
	Median	Middle Value; or the Average of the two middle values.
	Mode	The Number(s) that occur most Frequently.
Measures of Dispersion	Range	Difference between the Highest and Lowest numbers.
	Variance
	Standard Deviation	The square root of the variance: S	The square root of the variance:
	Skewness	The degree to which the Curve is Skewed to the Left or Right.
	Kurtosis	Rate of Change of the Curve.
	Standard Error of the Mean		N/A