TB No TB ID ID not 14 EXTRA PROBLEMS 85 Estimate the

# Tb no tb id id not 14 extra problems 85 estimate the

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TB No TB ID used 11 96 ID not used 35 1850
14 EXTRA PROBLEMS 85 Estimate the relative risk of developing TB in relation to the use of intravenous drug use from this study and interpret the result. 4. Suppose in a group of recent graduates, it was found that 28% had a law degree and 17% had a MBA. Five percent had both of these degrees. What is the probability that a randomly selected graduate has a MBA if they do not have a law degree? 5. A study was conducted to investigate a new procedure for detecting renal disease in patients with hypertension. Using the new procedure, experimenters screened a random sample of 200 hypertensive patients. Then the presence or absence of renal disease was determined by another method. The data obtained are shown in the following table: Disease Absent Disease Present Disease Detected by the New Procedure 16 21 Disease Not Detected by the New Procedure 157 6 What are the false-positive rate and false-negative rates for the new procedure? 6. We are interested in studying the survival rate of the marmot population on Mt. Washington. A marmot must survive last year to be encountered this year. Assume that survival and encounter probabilities are constant, the probability of surviving and being encountered is 0.40, and we encounter a marmot with probability 0.58. What is the probability that a marmot survives the year? 14.5 Set 6 Mutually exclusive and independence 1. Each member of a certain population of unhealthy patients has a risk of heart attack at levels low, medium, or high; and a risk of stroke at levels low, medium or high. The proportions of patients within each of the 9 categories are given in the following table. Risk of Risk of stroke heart attack Low Medium High Low 0.13 0.15 0.12 Medium 0.02 0.30 0.08 High 0.05 0.05 0.10 (a) Suppose that one patient is randomly chosen from this population. If the chosen patient has a medium or high risk of heart attack, what is the probability that the patient has only a low risk of a stroke? (b) Suppose that one patient is randomly chosen from this population. Which of the following statements are true? i. The events chosen patient has a low risk of heart attack and chosen patient has a high risk of stroke are independent. ii. The events chosen patient has a medium risk of heart attack and chosen patient has a medium risk of a stroke are mutually exclusive.
14 EXTRA PROBLEMS 86 iii. The events chosen patient has a low risk of stroke and chosen patient has a high risk of a stroke are mutually exclusive. (c) Suppose that two patients are randomly chosen from this population and that this pop- ulation is large. What is the probability that both patients have a high risk of stroke? 2. The following table is a result of classifying 1000 randomly selected car accident vehicles by the type of injury the driver sustained and the type of restraint used by the driver.