TDIST
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
TDIST(x,degrees_freedom,tails)
X is the numeric value at which to evaluate the distribution.
Degrees_freedom is an integer indicating the number of degrees of freedom.
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.
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.
- TDIST is calculated as TDIST = p( x<abs(X)), where X is a random variable that follows the t-distribution.
Example
X | Degrees | Formula | Description (Result) |
---|---|---|---|
1.96 | 60 | =TDIST([X],[Degrees],2) | Two-tailed distribution (0.054644927 or 5.46 percent) |
1.96 | 60 | =TDIST([X],[Degrees],1) | One-tailed distribution (0.027322463 or 2.73 percent) |