WorksheetFunction.TTest Method
Returns the probability associated with a Student's t-Test. Use TTEST to determine whether two samples are likely to have come from the same two underlying populations that have the same mean.
Syntax
expression.TTest(Arg1, Arg2, Arg3, Arg4)
expression A variable that represents a WorksheetFunction object.
Parameters
| Name | Required/Optional | Data Type | Description |
|---|---|---|---|
| Arg1 | Required | Variant | Array1 - the first data set. |
| Arg2 | Required | Variant | Array2 - the second data set. |
| Arg3 | Required | Double | Tails - specifies the number of distribution tails. If tails = 1, TTEST uses the one-tailed distribution. If tails = 2, TTEST uses the two-tailed distribution. |
| Arg4 | Required | Double | Type - the kind of t-Test to perform. |
Return Value
Double
Remarks
| If type equals | This test is performed |
|---|---|
| 1 | Paired |
| 2 | Two-sample equal variance (homoscedastic) |
| 3 | Two-sample unequal variance (heteroscedastic) |
- If array1 and array2 have a different number of data points, and type = 1 (paired), TTEST returns the #N/A error value.
- The tails and type arguments are truncated to integers.
- If tails or type is nonnumeric, TTEST returns the #VALUE! error value.
- If tails is any value other than 1 or 2, TTEST returns the #NUM! error value.
- TTEST uses the data in array1 and array2 to compute a non-negative t-statistic. If tails=1, TTEST returns the probability of a higher value of the t-statistic under the assumption that array1 and array2 are samples from populations with the same mean. The value returned by TTEST when tails=2 is double that returned when tails=1 and corresponds to the probability of a higher absolute value of the t-statistic under the "same population means" assumption.