# WorksheetFunction.ChiTest Method (Excel)

Office 2013

Published: July 16, 2012

Returns the test for independence.

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 .ChiTest(Arg1, Arg2)

expression A variable that represents a WorksheetFunction object.

### Parameters

Name

Required/Optional

Data Type

Description

Arg1

Required

Variant

The range of data that contains observations to test against expected values.

Arg2

Required

Variant

The range of data that contains the ratio of the product of row totals and column totals to the grand total.

Double

## Remarks

ChiTest returns the value from the chi-squared (χ 2 ) distribution for the statistic and the appropriate degrees of freedom. You can use χ 2 tests to determine whether hypothesized results are verified by an experiment.

• If actual_range and expected_range have a different number of data points, ChiTest returns the #N/A error value.

• The χ2 test first calculates a χ2 statistic using the formula: where: A ij = actual frequency in the i-th row, j-th column E ij = expected frequency in the i-th row, j-th column r = number or rows c = number of columns

• A low value of χ 2 is an indicator of independence. As can be seen from the formula, χ 2 is always positive or 0, and is 0 only if A ij = E ij for every i,j.

• ChiTest returns the probability that a value of the χ 2 statistic at least as high as the value calculated by the above formula could have happened by chance under the assumption of independence. In computing this probability, ChiTest uses the χ 2 distribution with an appropriate number of degrees of freedom, df. If r > 1 and c > 1, then df = (r - 1)(c - 1). If r = 1 and c > 1, then df = c - 1 or if r > 1 and c = 1, then df = r - 1. r = c= 1 is not allowed and generates an error.

• Use of ChiTest is most appropriate when E ij ’s are not too small. Some statisticians suggest that each E ij should be greater than or equal to 5.