The following data represent the discrete probability distribution for the number of stars that reviewers have a first edition s
tatistics 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 ________.
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 3 2 1 Total
Observed 28 28 13 6 5 80
Expected 20 28 16 8 8 80
chi square
(O_E)^2/E 3.2 0 0.5625 0.5 1.125 5.3875
p value =0.1455
Since p value >0.025, we accept H0
The expected requency of three-star reviews is ________.16
Each roll contains 80cm which is the same as 0.8 meters. Because he needs 5.6 meters, divide 5.6 by 0.8 and you 7. The seven is the number of rolls of tape he will need to purchase. Each roll costs $5 so multiply 7 by 5 and you will see that Carson will need to spend $35 if he wants to get that much tape. Hope that helps!
