Exam 11: Performance Evaluation Revisited: a Balanced Approach

Is the following a physical causal explanation or behavioral causal explanation? "He is not attending the concert because his ex-girlfriend is performing there."

Evaluate the following argument in accordance with the criteria discussed in the text. If you don't believe in God, you're much more likely to commit suicide. You can tell that by looking at places like Sweden and Norway where there's a higher percentage of atheists than the norm and their per capita suicide rate is higher, too.

Johnson is hired by a company to see if a new product, Topocal, will cause hair to grow on the heads of bald men. He recruits one thousand bald men and randomly divides them into two groups: Five hundred men (group A) rub Topocal on their scalps each day; the other five hundred (group B) rub a standard skin lotion on their scalps each day. After two months, Johnson checks to see what the results have been. He finds that there has been hair growth in 7 percent of group A and in 2 percent of group B.The category that best fits this study is

Evaluate the following argument in accordance with the criteria discussed in the text. A terrible squeaking noise from my tape recorder got so bad I couldn't stand to listen to my tapes anymore. I was sure the machine had developed a problem-and just a month after the warranty expired, too. So I cleaned the heads, the capstan, and all the moving parts, hoping I could make the noise go away. It remained. Then, just as I had decided I was going to have to take it in for repairs, I played some tapes belonging to a friend of mine, and the squeak wasn't there. So the problem is with my tapes, not my machine. I'm not sure I like that any better, since I've got dozens of them.

Evaluate the following generalization(s), identifying sample, population, attribute of interest, and the extent to which the claims involved are knowable. Consider carefully the size and diversification of the sample and the extent to which the population differs or may differ from the sample; remember, what's important is that the sample be representative. Fong notes that the pavement deteriorates as he crosses into the next county. "Guess they don't keep up their roads very well," he thinks.

In the following passage, identifying sample, population, attribute of interest, and the extent to which the claims involved are knowable. Consider carefully the size and diversification of the sample and the extent to which the population differs or may differ from the sample; remember, what's important is that the sample be representative. Do you find any flaw in our professor's reasoning about the usefulness of the survey for her own purposes? Should she believe that the more people who have home offices, the more likely her own will escape attention from the IRS? A college professor converted one room of her house into a home office and intended to deduct her expenses on her federal income tax return. She wondered how many other college faculty had done the same, thinking that the more who deducted home offices, the less likely her own return would be noticed by the IRS and hence the less likely she would be audited. So she decided to do her own informal survey of her colleagues to see how many of them had home offices. She sent out a questionnaire of three questions to all 1,200 instructors at her campus, and she received 950 responses. (Her promise to share the results of the survey apparently motivated faculty to respond.) As it turned out, 32 percent of her respondents answered yes to the question, "Do you maintain an office at home?" Half of these also answered yes to the question, "Do you deduct your home office expenses on your federal income tax return?" And 24 percent of the entire group of respondents answered yes to the question, "Is your campus office adequate?"

Lin sends away for a hot-cold serving tray she has seen advertised. The tray is promised to keep hot dishes hot and cold dishes cold without electricity. Lin tries it out by placing a pan of hot beans on it. They stay hot throughout dinner. "It works," she tells her husband. Do you think there could be a better test of the hot plate? Explain your response in a sentence or two.

A sample is random if

In evaluating the following generalization(s), identify sample, population, attribute of interest, and the extent to which the claims involved are knowable. Consider carefully the size and diversification of the sample and the extent to which the population differs or may differ from the sample; remember, what's important is that the sample be representative. A New York newspaper stopped theatergoers as they exited from a performance of La Tragédie de Carmen and asked them whether they thought that Broadway theater was better or worse than it was ten years ago. When the majority of the respondents answered that they thought it was worse, the paper printed an article with the headline "Public Thinks Broadway Is Going Downhill." Does the poll justify the headline?

Evaluate the following argument in accordance with the criteria discussed in the text. I'd wash the car but for the fact that we don't need any more rain.

Analyze the following study according to the criteria set by your instructor: We provided evidence that we could prevent myocardial infarction in angina patients, says Pierre Theroux of the Montreal Heart Institute. As reported in the New England Journal of Medicine (October 27, 1988), Theroux and his colleagues placed 479 hospitalized patients who had experienced chest pains into four treatment groups receiving either aspirin, heparin, a combination of the two, or a placebo. Heparin therapy reduced the rate of fatal and nonfatal heart attacks by 89 percent as compared with the placebo. It also reduced chest pain by 63 percent. Previous studies of heparin treatment of chest pain have produced questionable results, Theroux says. Aspirin therapy also helped: The Montreal team found that aspirin reduced the risk of heart attacks by 72 percent as compared with the placebo. But the combination aspirin/heparin treatment showed no particular benefit compared with aspirin alone or heparin alone, and patients getting the two drugs combined had a slightly higher risk of complications, such as bleeding. The researchers recommend, for patients hospitalized with chest pain, treatment with heparin upon admission followed by aspirin therapy for long-term management. -Adapted from Science News

In the following passage, identifying sample, population, attribute of interest, and the extent to which the claims involved are knowable. Consider carefully the size and diversification of the sample and the extent to which the population differs or may differ from the sample; remember, what's important is that the sample be representative. Would our professor's conclusion, "About 32 percent of college faculty nationwide maintain home offices," be more likely if she had included faculty from other institutions among her survey? Why? A college professor converted one room of her house into a home office and intended to deduct her expenses on her federal income tax return. She wondered how many other college faculty had done the same, thinking that the more who deducted home offices, the less likely her own return would be noticed by the IRS and hence the less likely she would be audited. So she decided to do her own informal survey of her colleagues to see how many of them had home offices. She sent out a questionnaire of three questions to all 1,200 instructors at her campus, and she received 950 responses. (Her promise to share the results of the survey apparently motivated faculty to respond.) As it turned out, 32 percent of her respondents answered yes to the question, "Do you maintain an office at home?" Half of these also answered yes to the question, "Do you deduct your home office expenses on your federal income tax return?" And 24 percent of the entire group of respondents answered yes to the question, "Is your campus office adequate?"

Evaluate the following generalization(s), identifying sample, population, attribute of interest, and the extent to which the claims involved are knowable. Consider carefully the size and diversification of the sample and the extent to which the population differs or may differ from the sample; remember, what's important is that the sample be representative. Gridley has been going to the Silver Dollar Fair every year for the past fifteen years. An acquaintance suggests they go to the fair, but "For God's sake, let's don't eat there, we'll die." Gridley knows better; he's never even once gotten sick from Silver Dollar food.

Make this inductive (statistical) syllogism into a strong argument by supplying an appropriate premise or conclusion: Greg must be into all that New Age stuff since he wears his hair in a ponytail.

In the following passage, identifying sample, population, attribute of interest, and the extent to which the claims involved are knowable. Consider carefully the size and diversification of the sample and the extent to which the population differs or may differ from the sample; remember, what's important is that the sample be representative. Is it reasonable for our professor to conclude that faculty office space on the campus is inadequate? A college professor converted one room of her house into a home office and intended to deduct her expenses on her federal income tax return. She wondered how many other college faculty had done the same, thinking that the more who deducted home offices, the less likely her own return would be noticed by the IRS and hence the less likely she would be audited. So she decided to do her own informal survey of her colleagues to see how many of them had home offices. She sent out a questionnaire of three questions to all 1,200 instructors at her campus, and she received 950 responses. (Her promise to share the results of the survey apparently motivated faculty to respond.) As it turned out, 32 percent of her respondents answered yes to the question, "Do you maintain an office at home?" Half of these also answered yes to the question, "Do you deduct your home office expenses on your federal income tax return?" And 24 percent of the entire group of respondents answered yes to the question, "Is your campus office adequate?"

Johnson is hired by a company to see if a new product, Topocal, will cause hair to grow on the heads of bald men. He recruits one thousand bald men and randomly divides them into two groups: Five hundred men (group A) rub Topocal on their scalps each day; the other five hundred (group B) rub a standard skin lotion on their scalps each day. After two months, Johnson checks to see what the results have been. He finds that there has been hair growth in 7 percent of group A and in 2 percent of group B)Given the size of Johnson's two groups, would you say that the results of the test are statistically significant?

Analyze the following study according to the criteria set by your instructor: As reported in the Journal of the American Medical Association, 26 surgeons-in-training were studied to see whether sleep deprivation impaired their patient-care ability. For 18 to 19 days the residents kept a sleep diary and underwent five tests each morning to measure cognition, visual and auditory alertness, and hand-eye coordination. Sleep deprivation was defined as less than 4 hours of continuous sleep in the previous 24 hours, which occurred in 89 percent of the on-duty nights studied. When sleep deprivation occurred, total sleep averaged 3 hours, and the longest uninterrupted sleep averaged 2.2 hours. Residents did show "trivial" improvement on two tests when they obtained some sleep just before testing, but the researchers said repetitive sleep deprivation did not impair the residents' test performances. The study "does not support arbitrary recommendations to limit working hours of residents," it was said. -Adapted from Science News

Evaluate the following argument in accordance with the criteria discussed in the text. Researchers in New Zealand discovered that the tiny dilly fish, which inhabit the country's fresh water streams, apparently get either excited or afraid when water flows increase. During the course of three seasons they noticed that the small egg-layers swim faster and jump out of the water more frequently when water flows were higher-the more water that ran through the streams the more dilly fish they'd find stranded on the banks. [This is a fictitious experiment.]

Evaluate the following analogical argument: The stock market has made huge gains during each of the past four years. I'm willing to put my money on the claim that it will do the same this coming year.

Lin sends away for a hot-cold serving tray she has seen advertised. The tray is promised to keep hot dishes hot and cold dishes cold without electricity. Lin tries it out by placing a pan of hot beans on it. They stay hot throughout dinner. "It works," she tells her husband. What type of argument or pattern of reasoning is employed?