# B 2 the prospective employee gets drug tested and the

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(b)(2)The prospective employee gets drug tested, and the test comes out to be positive. What isthe posterior probability that they are actually a user for the drug? (Answer this question basedon the tree)
(c)(1)When the employee finds out that they tested positive, they refuse the test results, and saythey would like to be tested again.What is the new prior probability you should use for thisemployee being a user of this drug?
(d)(1)The employee tests positive again in the second test.Should the new probability of themactually being a user of this drug be higher or lower than what you calculated before, or the same?
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6. (5 pts)City council survey. Match the followingA city council has requested a household survey be conducted in a suburban area of their city. Thearea is broken into many distinct and unique neighborhoods, some including large homes, some withonly apartments, and others a diverse mixture of housing structures. Match the appropriate samplingmethods.(1) Divide the city into neighborhoods, randomly sample 10 neighborhoods, and sample all house-holds from those neighborhoods.(2) Sample the 200 households closest to the city council oﬃces.(3) Randomly sample 50 households from the city.(4) Divide the city into neighborhoods, randomly sample 10 neighborhoods, and then randomly sam-ple 20 households from those neighborhoods.(5) Divide the city into neighborhoods, and sample 20 households from each neighborhood.(a) Simple random sampling.(b) Stratified sampling.(c) Cluster sampling. .(d) Multi-stage sampling.(e) Convenience sampling.Fill in the blanks - 2 points each (Total 10 points)For questions 7 to 11, fill in the blanks. Write legibly.7.(2)The difference between an observed and predicted response iscalled the.
8.(2)All else equal, a 99% confidence interval isthan a 90% confidence interval.
9.(2)An extraneous variable that is related to the explanatory and response variables and that preventsus from deducing causal relationships based on observational studies is called a.
10.(2)The probability of rejecting the null hypothesis when the null hypothesis is false iscalled the.
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11.(2)The theorem that describes the sampling distribution of a sample statistic is calledthe.
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Term
Fall
Professor
N/A
Tags
Statistical hypothesis testing, body fat percentage