代做MATH 524, Fall 2024 Nonparametric Statistics Third assignment代写留学生Matlab语言
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Nonparametric Statistics
Third assignment, due Monday, November 25, 2024, noon
1. The following table, from Dowling et al. (1957, J. Lab. Clin. Med.), shows the incidence of colds among 354 men, of whom 265 received an infectious secretion while the other 89 served as controls. Determine whether these results are statistically significant at the 1% level.
Developed a cold Did not develop a cold
Treated |
68 |
197 |
Control |
12 |
77 |
2. Among appendectomies of 103 female patients, age 10 to 29 years, the appendix of 60 patients was found to be pathological at operation while 43 were found to be normal. Of these patients, 65 were located for follow-up studies 9 to 12 years after the operation; 39 of them had had a pathological appendix and 26 a normal one.
The table below, from Meyer et al. (1964, Psychosomat. Med.), shows the number among these patients who did and did not have additional operations during the intervening period. Determine whether there is a significant difference between the two categories in this respect.
Appendix deemed to be pathological normal
No additional operations |
26 |
10 |
One or more additional operations |
13 |
16 |
3. The following table, also from Beecher (1959, Measurement of Subjec- tive Response), presents the total number of coughs per day of seven patients, under three different medications and a placebo administered in random order over a number of days:
Subject
1 2 3 4 5 6 7
Heroin, 5 mg |
251 |
126 |
49 |
45 |
233 |
291 |
1385 |
Dextromethorphan, 10 mg |
207 |
180 |
123 |
85 |
232 |
208 |
1204 |
Codein, 10 mg |
167 |
104 |
63 |
147 |
233 |
158 |
1611 |
Placebo |
301 |
120 |
186 |
100 |
250 |
183 |
1913 |
Is there a significant difference between the four treatments?
4. The following are the (smoothed) IQ scores of a child at the indicated ages (in years). Test the hypothesis of randomness against the alter- native of an upward trend.
Age 3 3.5 4 4.5 5 5.5 6
IQ Age |
105 7 |
110 8 |
109 9 |
114
10 |
114 11 |
115 12 |
114 |
IQ 118 123 128 128 127 126
5. Twelve mediation cases involving small businesses were ranked accord- ing to the success of the mediation effort and the amount of hostility shown in the early part of the process. The results are as follows:
Hostility 1 2 3 4 5 6 7 8 9 10 11 12
Success 12 7 10 11 4 1 8 9 3 6 2 5
Here 1 corresponds in the first row to the greatest amount of hostility, and in the second row to the greatest degree of success. Use Spearman’s rho and Kendall’s tau to test the hypothesis of independence against the alternative of a negative association of the two sets of ranks.
6. Let T1 , . . . , TN be a univariate time series and for i ∈ {1,..., N}, let Ri be the rank of Ti among T1 , . . . , TN . If D = (R1 −1)2 +···+(RN −N)2 , show that under the null hypothesis of randomness, one has
E(D) = 6/N3 − N and var(D) = 36/N2 (N + 1)2 (N − 1).
What are the smallest and largest values that D can take?
7. Suppose that in the same context as above, the ranks of T1 , . . . , TN should have been 1, . . . ,N in that order, but that because the first observation was misread, the ranks are R1 = N and Ri = i − 1 for i ∈ {2,..., N}. Given a significance level α ∈ (0, 1), determine how large N must be in order to reject the null hypothesis of randomness against the alternative of an upward trend.