**WHAT IS A T-TEST**

A T-Test is an analysis of two populations means through the use of statistical examination; a T-Test with two samples is commonly used with small sample sizes, testing the difference between the samples when the variances of two normal distributions are not known.

The test looks at the t-statistic, the t-distribution and degrees of freedom to determine the probability of difference between populations; the test statistic in the test is known as the t-statistic. To conduct a test with three or more variables, an analysis of variance (ANOVA) must be used.

## BREAKING DOWN THE TEST

A form of hypothesis testing, the test is just one of many tests used for this purpose. Statisticians must use tests other than the t-test to examine more variables, as well as for test with larger sample sizes. For a large sample size, statisticians use a z-test. Other testing options include the chi-square test and the f-test.

## TYPES

Sample‘t’ statistics are: