TTEST

Returns the probability associated with t-test. Determines whether two samples are likely to have come from the same two underlying populations that have the same mean.

Sample Usage

T.TEST(A1:A4, B1:B4, 2, 1)

Syntax

T.TEST(range1, range2, tails, type)

• range1 - The first sample of data or group of cells to consider for the t-test.

• range2 - The second sample of data or group of cells to consider for the t-test.

• tails - Specifies the number of distribution tails.

  • If 1: uses a one-tailed distribution.
  • If 2: uses a two-tailed distribution.

• type - Specifies the type of t-Test.

  • If 1: a paired test is performed.
  • If 2: a two-sample equal variance (homoscedastic) test is performed.
  • If 3: a two-sample unequal variance (heteroscedastic) test is performed.

Notes

• tails and type must be numeric.
• range1 and range2 must have the same number of data points.
• T.TEST uses the data in range1 and range2 to compute a non-negative test. If tails is set to 1, T.TEST returns the probability of a higher value of the t-statistic under the assumption that range1 and range2 are samples from populations with the same mean. The value returned by T.TEST when tails is set to 2 is double that returned when tails is set to 1 and corresponds to the probability of a higher absolute value of the t-statistic under the “same population means” assumption.
• You can use TTEST or T.TEST to perform this function.

Examples

In this example, a paired, two-tailed t-Test is computed on a student’s first and second quarter grades.