# WorksheetFunction.T_Dist_RT Method (Excel)

Office 2010

Returns the right-tailed 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 .T_Dist_RT(Arg1, Arg2)

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 that indicates the number of degrees of freedom.

Double

## Remarks

• If any argument is non-numeric, T_DIST_RT returns the #VALUE! error value.

• If degrees_freedom < 1, T_DIST_RT 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, T_DIST_RT returns the #NUM! error value.

• If x < 0, then T_DIST_RT returns the #NUM! error value.

• If tails = 1, T_DIST_RT is calculated as T_DIST_RT = P( X>x ), where X is a random variable that follows the t-distribution. If tails = 2, T_DIST_RT is calculated as T_DIST_RT = P(|X| > x) = P(X > x or X < -x).

• Because x < 0 is not allowed, to use T_DIST_RT when x < 0, note that T_DIST_RT(-x,df) = 1 – T_DIST_RT(x,df) = P(X > -x) and T_DIST_2T(-x,df) = T_DIST_2T(x df) = P(|X| > x).