A market research company was interested in comparing three communities A, B and C to determine whether there are any differences in their use of water filters in homes. Each of 100 homeowners sampled from each community was asked whether or not they have installed water-filtering system in their homes. Their responses (Yes or No) are summarized in the following contingency table.
a) Clearly state the null and alternative hypotheses in this problem.
b) Calculate the expected count for the bottom right cell (i.e., Community ‘C’ and ’No’), and explain what the number means.
c) The Chi-square statistic has been calculated to be 13.22. What can we conclude from this finding?