In column A you will find 1000 samples of the four strings L

In column A you will find 1000 samples of the four strings “L+”, “L-”, “R+”, “R-”. These represent results on sampling 1000 individuals for L/R handedness and diabetic/not (+/-). We wish to examine the proportion of diabetes among left handed individuals. In cells D2:D5 compile the frequency of the four possibilities, E2:E5 their relative frequencies. In cells D8 and D9 enter the observed proportions of diabetics and non-diabetics who are left handed. In cell D10 enter the observed proportion of left handed who are diabetic. Given that there is an 20% incidence of diabetes in the population as a whole, and a 10% incidence of left handedness, we wish to test the hypothesis that lateral favoritism does not influence the frequency of diabetes. Enter in cells F2:F5 the theoretically predicted probability of L+, L-, etc., and in E8:E10 the theoretically predicted conditional probabilities P(L|+), P(L|-), and P(+|L). Construct a symmetric about P(+|L) 90% confidence interval, based on the number of left handed observed, for the observed proportion “+|L” by giving its lower limit in H7 and upper limit in H8. Is the value in D10 in this interval? Enter your response (YES/NO) in G12.

Solution