T.DIST Function (DAX)

How does the T.DIST function (DAX) work?

The T.DIST function (DAX) returns the Student’s left-tailed t-distribution.

T.DIST Formula Syntax


How do you use the T.DIST function?

The t-distribution function 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.

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Considerations when using the T.DIST function

  • If any argument is non-numeric, TDIST returns the #VALUE! error value.
  • If Deg_freedom < 1, TDIST returns the #NUM! error value.
  • The Deg_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).

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Formula examples using the T.DIST function




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