Academic Integrity: tutoring, explanations, and feedback — we don’t complete graded work or submit on a student’s behalf.

Suppose that George has tossed a coin 52 times. The number of heads and tails wh

ID: 3181899 • Letter: S

Question

Suppose that George has tossed a coin 52 times. The number of heads and tails which resulted are shown below.

a.  Assuming the coin is "fair" (i.e., the probability of a head and a tail is equal), compute the expected frequencies for each outcome.

Enter your expected frequencies as whole numbers.

Expected number of heads =

Expected number of tails =

b.  After seeing the results, George claims the coin is not fair. He wants to conduct a chi-square goodness-of-fit test to investigate it further. Select the appropriate null hypothesis and alternative hypotheses.

H0:

Ha:

c.  Compute the value of the chi-square test statistic.

Round your intermediate chi-square terms to three decimal places. Round your answer to three decimal places.

Chi-square test statistic =

d. Determine the appropriate critical value at the 10% significance level.

Enter your critical value to three decimal places.

Critical value =

e. Select the appropriate initial conclusion.

f. Select the appropriate final conclusion.

Outcome Heads Tails Frequency 30 22

Explanation / Answer

The statistical software output for this problem is:

Chi-Square goodness-of-fit results:
Observed: Frequency
Expected: All cells in equal proportion

So,

a) Expected number of heads = 26

Expected number of tails = 26

b) H0: The coin is fair.

H1: The coin is not fair.

c) Test statistic = 1.231

d) Critical value = Chi - square value at 1 degree of freedom and 0.1 significance level = 3.841

e) Do not reject the null hypothesis.

f) Do not support the claim that the coin is unfair.

N DF Chi-Square P-value 52 1 1.2307692 0.2673