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The police department in Madison, Connecticut, released the following numbers of calls for the different days of the week during a February that had 28 days: Monday (114); Tuesday (152); Wednesday (160); Thursday (164); Friday (179); Saturday (196); Sunday (130). Use a 0.01 significance level to test the claim that the different days of the week have the same frequencies of police calls. Is there anything notable about the observed frequencies

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Answer:

different days of the week Do not have the same frequency.

Explanation:

Given the data:

Observed values :

Monday (114); Tuesday (152); Wednesday (160); Thursday (164); Friday (179); Saturday (196); Sunday (130).

H0 : frequency are the same

H1 : frequency is not the same

Expected value is the same for all days:

Σ (observed values) * 1/ n

n = number of days in a week. = 7

Expected value = (114+152+160+164+179+196+130) / 7 = 156.428

χ² = Σ (observed - Expected)²/Expected

χ² = (11.508 + 0.125 + 0.082 + 0.366 + 3.257 + 10.01 + 4.465)

χ² = 29.813

The Pvalue(29.813, 6) ;

df = 7 - 1 = 6

The Pvalue(29.813, 6) = 0.000043

α = 0.01

Since, Pvalue < α ; Reject H0 ; and conclude that, different days of the week Do not have the same frequency.

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