The following data represent the discrete probability distribution for the number of stars that reviewers have a first edition statistics reference book. stars 5 4 3 2 1 probability 25% 35% 20% 10% 10% the second edition of this reference book has been released and a random sample of people that have purchased the book has been collected with the following results. stars 5 4 3 2 1 frequency 28 28 13 6 5 the publisher would like to know if the probability distribution for reviews has changed from the first edition to the second edition using α = 0.025. the expected frequency of three-star reviews is

Step-by-step explanation:

given that the following data represent the discrete probability distribution for the number of stars that reviewers have a first edition statistics reference book.

Stars            5    4      3         2    1

Probability 25% 35% 20% 10% 10%

H0: Second edition is as per the above probabilities

Ha: atleast one is different from the above probability

(two tailed chi square test)

Alpha = 0.025

Assuming H0 to be true we calculate expected frequencies for total 80

chi square calculatons are shown below

df = 4

                  5     4         321      Total

Observed28    281365      80

Expected20    281688      80

chi square        

(O_E)^2/E3.200.56250.51.1255.3875

p value =0.1455

Since p value >0.025, we accept H0

The expected requency of three-star reviews is .16

the answer is c. 23/3