Question 188975
High levels of cockpit noise in an aircraft can damage the hearing of pilots who are exposed to this hazard for many hours. A Boeing 727 co-pilot collected 61 noise observations using a handheld sound meter. Noise level is defined as “Low” (under 88 decibels), “Medium” (88 to 91 decibels),or “High” (92 decibels or more). There are three flight phases (Climb, Cruise, Descent).
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Research question: At α = .05, is the cockpit noise level independent of flight phase? 
(Data are from Capt. Robert E. Hartl, retired.) Noise
Noise Level Climb Cruise Descent Row Total
Low 6 2 6 14
Medium 18 3 8 29
High 1 3 14 18
Col Total 25 8 28 61
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Ho: The row and column factors are not related
Ha: They are related
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Run a Chi-Sq on the 3 by 3 set of data.
I get test statistic Chi-Sq = 15.16
p-value = 0.0044
df = (3-1)(3-1)= 4
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Conclusion:
Since the p-value is less than 5%, reject Ho.
Noise levels are related to flight configuration.
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Cheers,
Stan H.