Suppose we are conducting a hypertension-screening program in the home. Consider all possible pairs of DBP measurements of the mother and father within a given mixed gender family, assuming that the mother and father are not genetically related. In particular, we might be interested in whether the mother or father is hypertensive, which is described, respectively, by events A = {mother's DBP ≥ 90), B = (father's DBP ≥ 90). Suppose we know that Pr(A) = 0.09 Pr(B) = 0.21. Let X be the random variable representing the number of hypertensive adults a given mixed gender family. (a) Derive the probability-mass function for X. Pr(x = x) x 0 1 2 1 1 1 X (c) What is its variance? x x (b) What is its expected value?

PM Wed Nov 3 Stats Home Insert Draw View 8). Studies have shown that drivers who use cell phones while operating a motor passenger vehicle increase their risk of an accident. To quantify this risk, the New England Journal of Medicine (January 2, 2014) reported on the risk of a crash (or near crash) for both novice and expert drivers when using a cell phone. In a sample of 371 cases of novices using a cell phone while driving, 24 resulted in a crash (or near crash). In a sample of 1,467 cases of experts using a cell phone while driving. 67 resulted in a crash (or near crash). a). Find a 93% confidence interval for p, the true crash risk (probability) for novice drivers, also indicating the ME value. Answer: ME = b). Find a 93% confidence interval for p, the true crash risk (probability) for expert drivers, also indicating the ME value. Answer: гр, ME =

Is the national crime rate really going down? Some sociologists say yes! They say that the reason for the decline in crime rates in the 1980s and 1990s is demographics. It seems that the population is aging, and older people commit fewer crimes. According to the FBI and the Justice Department, 70% of all arrests are of males aged 15 to 34 years†. Suppose you are a sociologist in Rock Springs, Wyoming, and a random sample of police files showed that of 33arrests last month, 25were of males aged 15 to 34 years. Use a 1%level of significance to test the claim that the population proportion of such arrests in Rock Springs is different from 70%.  a. What is the level of significance? answer   .01 b.State the null and alternate hypotheses. Which one? Its the third. H0: p< 0 .7; H1: p= 0.7 H0: p≠0.7; H1: p= 0.7     H0: p= 0.7; H1: p≠0.7 H0: p= 0 .7; H1: p< 0.7 H0: p= 0.7; H1: p> 0.7   c. What sampling distribution will you use? Its the last one. The Student's t, since np> 5 and…

A new screening test for Lyme disease is developed for use in the general population. The sensitivity and specificity of the new test are 60% and 70%, respectively. Five hundred people are screened at a clinic during the first year the new test is implemented. Assume the true prevalence of Lyme disease among clinic attendees is 10%. Calculate the predictive value of a positive test.