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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

User Radde Mojsovski
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19 votes

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.

User Cartroo
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