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Statement of a problem № m102808



This cumulative review problem uses material from Chapters 3, 5, and 10. Recall that the Poisson distribution deals with rare events. Death from the kick of a horse is a rare event, even in the Prussian army. The following data are a classic example of a Poisson application to rare events. A reproduction of the original data can be found in C. P. Winsor, Human Biology, Vol. 19, pp. 154-161. The data represent the number of deaths from the kick of a horse perarmy corps per year for 10 Prussian army corps for 20 years (1875-1894). Let x represent the number of deaths and f the frequency of x deaths. (a) First, we t the data to a Poisson distribution (see Section 5.4). Poission distribution: Where λ ≈ x̅ (sample mean of x values) From our study of weighted averages (see section 3.1), Verify that x̅ ≈ 0.61 For the category 3 or more, use 3. (b) Now we have 1, 2, 3. p Find P(0), P(1), P(2), and P(3 ≤ x). Round to three places after the decimal. (c) The total number of observations is ∑f = 200. For a given x, the expected frequency of x deaths is 200P(x). The following table gives the observed frequencies O and the expected frequencies E = 200P(x). (d) State the null and alternate hypotheses for a chi-square goodness-of-t test. Set the level of significance to be a = 0.01. Find the P-value for a goodness-of-t test. Interpret your conclusion in the context of this application. Is there reason to believe that the Poisson distribution fits the raw data pro




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