WorksheetFunction.ChiSq_Test Method (Excel)
Returns the test for independence.
Version Information
Version Added: Excel 2010
Syntax
expression .ChiSq_Test(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. |
Return Value
Double
Remarks
ChiSq_Test 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, ChiSq_Test returns the #N/A error value.
The χ2 test first calculates a χ2 statistic using the formula:
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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 columnsA 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.
ChiSq_Test 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, ChiSq_Test 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 ChiSq_Test 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.