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

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

N/A 