use the Kruskal - Wallis test with the data set from Appendix B?. IQ and Lead Exposure? Data Set in Appendix B lists performance IQ scores for random samples of subjects with blood lead levels categorized as low, medium, and high. Use a 0.01 significance level to test the claim that subjects in those categories have the same median per?formance IQ score. Does lead exposure appear to have an adverse effect? Mile 1 3:15 3:24 3:23 3:22 3:21 Mile 2 3:19 3:22 3:21 3:17 3:19 Mile 3 3:34 3:31 3:29 3:31 3:29

Solution 9BSC Step 1 By using = 0.01 level of significance to test the claim that subjects in those categories have the same median performance IQ score. The Hypotheses can be expressed as H : subjects in those categories have the same median performance IQ score. 0 H1 subjects in those categories have the different median performance IQ score. The test statistic can be found by using MINITAB as shown below From the MINITAB output, we have H = 8.01 is the required value of test statistic and P-value = 0.018. The smaller P-value is, the stronger the evidence against H and in favor of H0 If 1 P-value is small like 0.01 or smaller, we may conclude that the null hypothesis H is 0 strongly rejected in favor of H . If p-value is between 0.05 P-value 0.01, we may 1 conclude that the null hypothesis H is rejecte0in favor of H . In other cases, 1e., P-value > 0.05, we may conclude that the null hypothesis H is accepted. 0 Since P-value lies in between 0.01 and 0.05 we reject the null hypothesis and conclude that there is no sufficient efficient to claim that subjects in those categories have the same median performance IQ score and hence lead exposure does not appear to have an adverse effect.