In: Statistics and Probability
This question refers to a sweepstakes promotion in which respondents were asked to select what color car they would like to receive if they had the winning number. For a random sample of respondents the choices were 24 blue (B), 34 green(G), 66 red(R), and 36 white(W). Test at the 0.05 level the claim that the population prefers each colour equally. The expected value of chi-square (the test statistics) is
Select one:
a. 7.815
b. 24.600
c. 0
d. 22.412
e. 9.488
This question refers to a sweepstakes promotion in which respondents were asked to select what color car they would like to receive if they had the winning number. For a random sample of respondents the choices were 24 blue (B), 34 green(G), 66 red(R), and 36 white(W). Test at the 0.05 level the claim that the population prefers each colour equally. The critical value chi_square_c is
Select one:
a. 9.488
b. 24.600
c. 22.412
d. 0
e. 7.815
Solution:
Given:
claim: the population prefers each colour equally.
We have to find The expected value of chi-square (the test statistics).
Chi square test statistic for goodness of fit
Where
Oi = Observed Counts
Ei =Expected Counts = N / k = 160 / 4 = 40
Thus we need to make following table
Color | Oi | Ei | Oi^2/Ei |
---|---|---|---|
Blue | 24 | 40 | 14.4 |
Green | 34 | 40 | 28.9 |
Red | 66 | 40 | 108.9 |
White | 36 | 40 | 32.4 |
160 |
Thus
Thus correct answer is:
b. 24.600
Part b) The critical value chi_square_c =.......?
df = k - 1= 4 - 1= 3
level of significance = 0.05
Chi-square critical value = 7.815