# TTest2 Command

From GeoGebra Manual

- TTest2( <List of Sample Data 1>, <List of Sample Data 2>, <Tail>, <Boolean Pooled> )
- Performs a t-test of the difference between two population means using the given lists of sample data. Tail has possible values "<", ">" , "≠" that determine the following alternative hypotheses:
- "<" = difference in population means < 0
- ">" = difference in population means > 0
- "≠" = difference in population means ≠ 0

- If
*Pooled*= true, then population variances are assumed equal and sample standard deviations are combined in calculation. - If
*Pooled*= false, then population variances are not assumed equal and sample standard deviations are not combined.

- If
- Results are returned in list form as
*{Probabilty value, t-test statistic}*.

- TTest2( <Sample Mean 1>, <Sample Standard Deviation 1>, <Sample Size 1>, <Sample Mean 2>, <Sample Standard Deviation 2>, <Sample Size 2>, <Tail>, <Boolean Pooled> )
- Performs a t-test of the difference between two population means using the given sample statistics.
*Tail*and*Pooled*are defined as above. Results are returned in list form as*{Probabilty value, t-test statistic}*.