In: Statistics and Probability
what is the difference between chi square and z test?
Solution:
The z-test is used to test the following test:
1) To test whether the population mean is different from the some hypothesized value of population mean or not.
2) To test whether there is any significant difference between two population means or not.
3) To test whether the population proportion is different from the hypothesized value of population proportion or not.
4) To test whether there is significant difference between two population proportions or not.
Z-test is parametric test and it is used for large sample sizes.
The chi-square test is used for following tests:
1) To test the goodness of fit.
2) To test the independence of attributes.
3) To test whether the population variance is different from some hypothesized value of population variance or not.
The chi square test given in (1) and (2) are non parametric tests, whereas chi square test given in (3) is parametric test. It is used for small samples.