Table 12.4 on page 482 showed the calculated sums of the observed frequencies, the expected frequencies, and their differences.
Strictly speaking, those sums are not needed. However, they serve as a check for computational errors.
a. In general, what common value should the sum of the observed frequencies and the sum of the expected frequencies equal? Explain your answer.
b. Fill in the blank. The sum of the differences between each observed and expected frequency should equal.
c. Suppose that you are conducting a chi-square goodness-of-fit test. If the sum of the expected frequencies does not equal the sample size, what do you conclude?
d. Suppose that you are conducting a chi-square goodness-of-fit test. If the sum of the expected frequencies equals the sample size, can you conclude that you made no error in calculating the expected frequencies? Explain your answer.