If the expected frequency for any cell i is less than 5, we:
A) must choose another sample of five or more observations
B) should use the normal distribution instead of the chi-square distribution
C) should combine the cells such that each observed frequencyis 5 or more
D) increase the number of degrees of freedom for the test by 5
E) all of these

Question

If the expected frequency  for any cell i is less than 5, we:
A) must choose another sample of five or more observations 
B) should use the normal distribution instead of the chi-square distribution 
C) should combine the cells such that each observed frequencyis 5 or more 
D) increase the number of degrees of freedom for the test by 5 
E) all of these

Quizplus · Accepted Answer

If the expected frequency for any cell is less than 5, it can lead to unreliable results and violates the assumption of the chi-square test. Therefore, we need to combine the cells such that each observed frequency is 5 or more, which increases the expected frequency and reduces the risk of type-II error. Choosing another sample or using the normal distribution instead of the chi-square distribution does not address the issue of low expected frequency, and increasing the number of degrees of freedom could even worsen the problem.

If the Expected Frequency for Any Cell I Is