For the past 16 years, the yields of wheat (in tons) grown on a plot at Rothamsted Experimental Station (England) follow. The sequence is by year.

Use level of signifi­cance 5% to test for randomness about the median.

(a) State the test used.

(b) Give a. State the null and alternate hypotheses.

(c) Find the sample test statistic.

(d) For the sign test, rank-sum test, and Spearman correlation coef­ficient test, fi­nd the P-value of the sample test statistic. For the runs test of randomness, ­find the critical values from Table 10 of Appendix II.

(e) Conclude the test and interpret the results in the context of the application

Transcribed Image Text:

3.8 1.9 0.6 1.7 2.0 3.5 3.0 1.4 2.7 2.3 2.6 2.1 24 2.7 1.8 1.9