The IQ scores for a random sample of subjects with medium lead levels in their blood and another randomsample of subjects with high lead levels in their blood are given below. Use a 0.05 significance level to test theclaim that subjects with medium lead levels have full IQ scores with a higher median that the median full IQscore for subjects with high lead levels. Does lead level appear to affect full IQ scores?Click the icon to view the data table.First define the null and alternative hypotheses.Ho: The two samples come from populations with equal medians.H₁: The medium lead level population has a higher median IQ than the high lead level population.Identify the test statistic. Let the medium lead level be sample 1.Z=(Round to two decimal places asData TableLet the medium lead level be sample 1.Medium Lead High LeadLevelLevel669864876384707370787211310783849161887376636661646166927610766X

Given the data as Medium Lead Level High Lead Level 66 91 98 61 64 88 87 73 63 76 84 63 70 66 73 61 70 64 78 61 72 66 113 92 107 76 83 107 84 66 The null and alternate hypotheses are H0 : The two samples come from populations with equal medians H1 : The medium lead level population has a higher median IQ than the high lead level population Consider both data as a single data and arrange in ascending order Lead level 61 61 61 63 63 64 64 66 66 66 66 70 70 72 73 73 76 76 78 83 84 84 87 88 91 92 98 107 107 113 The median of the overall data=73+732=73 Observed frequencies : Medium High Total >Overall median 8 6 14 ≤Overall median 7 9 16 Total 15 15 30 The test statistic is χ2=∑Oi-Ei2Ei~χr-1c-12 i Observed frequenciesOi Expected frequencies Ei Oi-Ei2Ei 1 8 14×1530=7 0.1429 2 6 14×1530=7 0.1429 3 7 16×1530=8 0.125 4 9 16×1530=8 0.125 Total 30 30 0.5358 χ2=∑Oi-Ei2Ei=0.5358 df=r-1×c-1=2-1×2-1=1 Critical value, χ0.05,12=CHISQ.INV.RT(0.05,1)=3.841 {using EXCEL} Since the calculated value is less than the critical chi-square value, we fail to reject the null hypothesis at 5% level of significance and hence conclude that there is significant evidence that the two samples come from populations with equal medians.