Question

2. An interesting and popular hypothesis is that individuals can temporarily postpone death to survive a major holiday or important event such as a birthday. In a study, it was found that there were 6062 deaths in the week before Thanksgiving, and 5938 deaths the week after Thanksgiving (based on data from “Holidays, Birthdays, and Postponement of Cancer Death,” by Young and Hade, Journal of the American Medical Association, Vol. 292, No. 24).

   (a) If people can postpone death until after Thanksgiving, then the proportion of deaths in the week before should be less than 50%. By hand, use the p-value method and a 0.10 significance level to test the claim that the proportion of deaths in the week before Thanksgiving is less than 50%. Use excel to confirm the p-value you found. Hint: the command =norm.s.dist(test statistic, true) finds the left tail probability for z. (b) Based on the result, does there appear to be any indication that people can temporarily postpone death to survive the Thanksgiving holiday? (c) Suppose the hypothesis test in a) was to find if the proportion is different from 50%; redo the hypothesis test by hand using the p-value method and compare the results. Confirm your p-value using excel.

Answer 1

(a)

Sample size: n = 6062+5938 = 12000

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Conclusion: There is evidence to conclude that the proportion of deaths in the week before Thanksgiving is less than 50%.

(b)

Yes, based on the result, there appears to be any indication that people can temporarily postpone death to survive the Thanksgiving holiday.

(c)

Conclusion: There is no evidence to conclude that the proportion of deaths in the week before Thanksgiving is not equal to 50%.