WorksheetFunction.TDist Method
Returns the Percentage Points (probability) for the Student t-distribution where a numeric value (x) is a calculated value of t for which the Percentage Points are to be computed. The t-distribution is used in the hypothesis testing of small sample data sets. Use this function in place of a table of critical values for the t-distribution.
Syntax
expression.TDist(Arg1, Arg2, Arg3)
expression A variable that represents a WorksheetFunction object.
Parameters
| Name | Required/Optional | Data Type | Description |
|---|---|---|---|
| Arg1 | Required | Double | X - the numeric value at which to evaluate the distribution. |
| Arg2 | Required | Double | Degrees_freedom - an integer indicating the number of degrees of freedom. |
| Arg3 | Required | Double | Tails - specifies the number of distribution tails to return. If tails = 1, TDIST returns the one-tailed distribution. If tails = 2, TDIST returns the two-tailed distribution. |
Return Value
Double
Remarks
- If any argument is nonnumeric, TDIST returns the #VALUE! error value.
- If degrees_freedom < 1, TDIST returns the #NUM! error value.
- The degrees_freedom and tails arguments are truncated to integers.
- If tails is any value other than 1 or 2, TDIST returns the #NUM! error value.
- If x < 0, then TDIST returns the #NUM! error value.
- If tails = 1, TDIST is calculated as TDIST = P( X>x ), where X is a random variable that follows the t-distribution. If tails = 2, TDIST is calculated as TDIST = P(|X| > x) = P(X > x or X < -x).
- Since x < 0 is not allowed, to use TDIST when x < 0, note that TDIST(-x,df,1) = 1 - TDIST(x,df,1) = P(X > -x) and TDIST(-x,df,2) = TDIST(x df,2) = P(|X| > x).