WorksheetFunction.TInv Method (Excel)
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# WorksheetFunction.TInv Method (Excel)

Office 2010

Returns the t-value of the Student's t-distribution as a function of the probability and the degrees of freedom.

Important

This function has been replaced with one or more new functions that may provide improved accuracy and whose names better reflect their usage. This function is still available for compatibility with earlier versions of Excel. However, if backward compatibility is not required, you should consider using the new functions from now on, because they more accurately describe their functionality.

## Syntax

expression .TInv(Arg1, Arg2)

expression A variable that represents a WorksheetFunction object.

### Parameters

Name

Required/Optional

Data Type

Description

Arg1

Required

Double

Probability - the probability associated with the two-tailed Student's t-distribution.

Arg2

Required

Double

Degrees_freedom - the number of degrees of freedom with which to characterize the distribution.

Double

## Remarks

• If either argument is nonnumeric, TINV returns the #VALUE! error value.

• If probability < 0 or if probability > 1, TINV returns the #NUM! error value.

• If degrees_freedom is not an integer, it is truncated.

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

• TINV returns that value t, such that P(|X| > t) = probability where X is a random variable that follows the t-distribution and P(|X| > t) = P(X < -t or X > t).

• A one-tailed t-value can be returned by replacing probability with 2*probability. For a probability of 0.05 and degrees of freedom of 10, the two-tailed value is calculated with TINV(0.05,10), which returns 2.28139. The one-tailed value for the same probability and degrees of freedom can be calculated with TINV(2*0.05,10), which returns 1.812462. Given a value for probability, TINV seeks that value x such that TDIST(x, degrees_freedom, 2) = probability. Thus, precision of TINV depends on precision of TDIST.

Note

In some tables, probability is described as (1-p).