Classifies and tallies objects of experimentation according to two schemes of categorization. Details
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Table is the input contingency table specified as an array of counts or frequencies. |
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x specifies the value at which you wish to interpolate a corresponding y value. |
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probability must be greater than or equal to zero and less than or equal to one (0.0 <= p <= 1.0). If probability is out of range, the VI sets x to NaN and returns an error. |
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error returns any error or warning condition from the VI. |
With the test of homogeneity, the VI takes a random sample of some fixed size from each of the categories in one categorization scheme. For each of the samples, the VI categorizes the objects of experimentation according to the second scheme and tallies them. The VI tests the hypothesis to determine whether the populations from which each sample is taken are identically distributed with respect to the second categorization scheme.
With the test of independence, the VI takes only one sample from the total population. The VI then categorizes each object and tallies it in two categorization schemes. The VI tests the hypothesis that the categorization schemes are independent.
You must choose a level of significance for each test that specifies how likely you want it to be that the VI rejects the hypothesis when it is true. Ordinarily, you do not want it to be very likely. Use a small number, 0.05 is a common choice, to determine the level of significance. The output parameter probability is the level of significance at which the hypothesis is rejected. Thus, if probability is less than the level of significance, you must reject the hypothesis.
Let be the number of occurrences in the
cell of the contingency table for
p = 0, 1,..., (s 1) and q = 0, 1,..., (k 1),
where s is the number of rows in the Contingency Table, and k is the number of columns in the Contingency Table.
Let
The VI uses x to calculate the probability
where X is a random variable from the distribution. If the hypothesis is true, x came from a
distribution with (s 1) and (k 1) degrees of freedom.