If omitted, the sample standard deviation is used. Alpha is the significance level used to compute the confidence level. Size is the sample size. Array1 is the first data set. Array2 is the second data set.
Tails specifies the number of distribution tails.
Type is the kind of t-test to perform. 1 Range Enter the cell reference for the first range of data you want to analyze. The range must consist of a single column or row. Variable 2 Range Enter the cell reference for the second range of data you want to analyze. The range must consist of a single column or row.