Compatibility - CHITEST Function

The CHITEST function replaces the CHISQ.TEST function in Excel 2010.

Description

The function returns the test for independence. CHITEST returns the value from the chi-squared (X²) distribution for the statistic and the appropriate degrees of freedom. You can use X² tests to determine whether hypothesized results are verified by an experiment.

Syntax

HITEST (actual_range,expected_range)

Arguments

Notes

• The $X^2$ test first calculates a $X^2$ statistic using the formula −

  $$X^2 = \sum_{i=1}^{r}\sum_{j=1}^{c}\frac{(A_{ij} - E_{ij})^2}{E_{ij}}$$

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 of rows

$c$ = number of rows

• A low value of $X^2$ is an indicator of independence. As can be seen from the formula, $X^2$ 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 X² 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 X² 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 #N/A is returned.

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

• Use of CHITEST is most appropriate when the values of $E_{ij}$ are not too small. Some statisticians suggest that each $E_{ij}$ should be greater than or equal to 5.

Example