A group of researchers have developed a new test for Covid-19. They used it on 1024 patients and discovered that the test has a false positive rate of 25% and a false negative rate of 75%. For 736 patients in this sample, the test result was wrong (either false positive, or false negative). (a) Based on this data, can we say that the test result is independent of the patient's disease status (diseased or non-diseased)? (b) Report the PPV and NPV of this test. (a) no; (b) PPV=0.8245, NPV=0.1755 (a) yes; (b) PPV=0.7188, NPV=0.2812 (a) no; (b) PPV=0.7188, NPV=0.2812 (a) yes; (b) PPV=0.9375, NPV=0.0625 (a) no; (b) PPV=0.9375, NPV=0.0625 In the United States, 42% of the population has blood type A. We select a random sample of 16 Americans. Using R, we would like to calculate the probability of observing between 4 and 7 persons (including these values) who have blood type A. Consider the following five R commands: (a) pbinom(7,16,0.42)-pbinom(4,16,0.42) (b) pbinom(7,16,0.42)-dbinom(4,16,0.42) (c) pbinom(4,16,0.42)-pbinom(7,16,0.42) (d) pbinom(7,16,0.42)-pbinom(3,16,0.42) (e) pbinom(7,16,0.42)-pbinom(4,16,0.42)+dbinom(4,16,0.42). Which one of the following statements is correct? Only command (d) gives the correct answer. Only command (a) gives the correct answer. Both commands (a) and (d) give the correct answer. Only command (e) gives the correct answer. Both commands (d) and (e) give the correct answer. Occupational medicine is a branch of clinical medicine concerned with keeping people well at work and identifying health hazards for particular occupations. In a group of 46 male fire fighters with age between 25 and 36, we measured the change in the pulmonary function over a period of 5 years. One variable of interest was the forced expiratory volume (FEV), which is the volume of air expelled in one second. At the end of this period, it was found that the fire fighters had a mean decline in FEV of 0.27 liters, with a sample standard deviation of 0.52 liters. The FEV is known to decline by 0.1 liters for healthy men in the same age group, over the same period of time. Can we conclude that the occupation of fire fighters causes a decline in FEV significantly higher than 0.1 liters, and therefore should be considered a health hazard? Choose and conduct an appropriate hypothesis test. Report the p-value of your test, and state your conclusion at level a = 0.02. p-value > 0.02; we can say that the occupation of fire fighter causes a significant decline in FEV The sample size is not large enough for conducting a meaningful test. p-value 0.02; we cannot say that the occupation of fire fighter causes a significant decline in FEV A group of researchers have developed a new test for Covid-19. They used it on 1024 patients and discovered that the test has a false positive rate of 25% and a false negative rate of 75%. For 736 patients in this sample, the test result was wrong (either false positive, or false negative). (a) Based on this data, can we say that the test result is independent of the patient's disease status (diseased or non-diseased)? (b) Report the PPV and NPV of this test. (a) no; (b) PPV=0.8245, NPV=0.1755 (a) yes; (b) PPV=0.7188, NPV=0.2812 (a) no; (b) PPV=0.7188, NPV=0.2812 (a) yes; (b) PPV=0.9375, NPV=0.0625 (a) no; (b) PPV=0.9375, NPV=0.0625 In the United States, 42% of the population has blood type A. We select a random sample of 16 Americans. Using R, we would like to calculate the probability of observing between 4 and 7 persons (including these values) who have blood type A. Consider the following five R commands: (a) pbinom(7,16,0.42)-pbinom(4,16,0.42) (b) pbinom(7,16,0.42)-dbinom(4,16,0.42) (c) pbinom(4,16,0.42)-pbinom(7,16,0.42) (d) pbinom(7,16,0.42)-pbinom(3,16,0.42) (e) pbinom(7,16,0.42)-pbinom(4,16,0.42)+dbinom(4,16,0.42). Which one of the following statements is correct? Only command (d) gives the correct answer. Only command (a) gives the correct answer. Both commands (a) and (d) give the correct answer. Only command (e) gives the correct answer. Both commands (d) and (e) give the correct answer. Occupational medicine is a branch of clinical medicine concerned with keeping people well at work and identifying health hazards for particular occupations. In a group of 46 male fire fighters with age between 25 and 36, we measured the change in the pulmonary function over a period of 5 years. One variable of interest was the forced expiratory volume (FEV), which is the volume of air expelled in one second. At the end of this period, it was found that the fire fighters had a mean decline in FEV of 0.27 liters, with a sample standard deviation of 0.52 liters. The FEV is known to decline by 0.1 liters for healthy men in the same age group, over the same period of time. Can we conclude that the occupation of fire fighters causes a decline in FEV significantly higher than 0.1 liters, and therefore should be considered a health hazard? Choose and conduct an appropriate hypothesis test. Report the p-value of your test, and state your conclusion at level a = 0.02. p-value > 0.02; we can say that the occupation of fire fighter causes a significant decline in FEV The sample size is not large enough for conducting a meaningful test. p-value 0.02; we cannot say that the occupation of fire fighter causes a significant decline in FEV