In a certain clinical trial, a medical team wants to study four different doses of a new medication for cervical cancer in five patients. In how many different ways can the team select one dose of the medication and one of the patients?

Bonnie and her friends are dubious that a new abdominal exercise machine is as effective as its commercial claims. They decide to conduct an experiment to find out. For three months, Bonnie has 25 randomly chosen friends use the new machine, and 25 others do traditional abdominal exercises. At the end of the experiment, she counts the number of sit-ups each friend can do in one minute. No. of sit-ups for friends who use machine 43 29 41 22 43 28 35 26 31 48 41 24 48 25 23 35 25 28 28 31 27 45 41 22 46 Mean: 33.4 sit-ups No. of sit-ups for friends who do traditional exercises 44 33 33 24 49 39 21 45 44 48 47 50 43 46 29 46 45 32 36 41 49 45 28 49 29 Mean: 39.8 sit-ups How much lower is the average for the treatment group than the average for the control group? sit-ups

Alcohol and estrogen After menopause, some womentake supplemental estrogen. There is some concern thatif these women also drink alcohol, their estrogen levelswill rise too high. Twelve volunteers who were receivingsupplemental estrogen were randomly divided into twogroups, as were 12 other volunteers not on estrogen. Ineach case, one group drank an alcoholic beverage, theother a nonalcoholic beverage. An hour later, everyone’sestrogen level was checked. Only those on supplementalestrogen who drank alcohol showed a marked increase.

If samples of a fixed size N are drawn randomly and with replacement from the same population of scores, should we expect the sample means to differ across samples? why or why not?

Twenty university students chosen at random from students enrolled at Carthage College took part in an experiment testing the effect of watching ABC News versus CNN on knowledge of world events. The 20 participants were divided randomly into two equal groups of 10 students each. One group was assigned to watch ABC and the other was assigned to watch CNN. Participants then watched their assigned station (ABC or CNN) for 3 hours a night for 4 weeks. At the end of the 4 week period they were administered a test of world knowledge. The results were as follows: XbarABC = 104; sABC = 12 XbarCNN = 99; sCNN = 10 Compute the 95% confidence interval around the difference between the two groups.

A car dealer is interested in comparing the average gas mileages of four different car models. The dealer believes that the average gas mileage of a particular car will vary depending on the person who is driving the car due to different driving styles. Because of this, he decides to use a randomized block design. He randomly selects five drivers and asks them to drive each of the cars. He then determines the average gas mileage for each car and each driver. Can the dealer conclude that there is a significant difference in average gas mileages of the four car models? The results of the study are as follows.  Average Gas Mileage Driver Car A Car B Car C Car D Driver 1 3232 2222 3030 3939 Driver 2 2121 3939 3838 3737 Driver 3 2626 3131 3232 3939 Driver 4 3838 4040 2323 3434 Driver 5 3131 2929 2121 2222 Copy Data ANOVA Source of Variation SSSS dfdf MSMS Rows 174.2000174.2000 44 43.550043.5500 Columns 91.600091.6000 33 30.533330.5333 Error 607.4000607.4000 1212…

In the largest clinical trial ever conducted, 401,974 children were randomly assigned to two groups. The treatment group consisted of​ 201,229 children given the Salk vaccine for​ polio, and the other​ 200,745 children were given a placebo. Among those in the treatment​ group, 33 developed​ polio, and among those in the placebo​ group, 115 developed polio. If we want to use the methods for testing a claim about two population proportions to test the claim that the rate of polio is less for children given the Salk​ vaccine, are the requirements for a hypothesis test​ satisfied? Explain.   A The requirements are not​ satisfied; the samples are not simple random samples that are independent.   B. The requirements are​ satisfied; the samples are simple random samples that are​ independent, and for each of the two​ groups, the number of successes is at least 5 and the number of failures is at least 5.   C. The requirements are​ satisifed; the samples are simple random samples…

A biologist wants to determine if different temperatures (15oC, 25oC, or 35oC) and amounts of sunlight (partial or full) will affect the growth of plants. He will test each combination of temperature and sunlight by randomly assigning 15 plants to each of the combinations. What type of sampling is described in this study? one sample paired data two samples more than two samples

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A car dealer is interested in comparing the average gas mileages of four different car models. The dealer believes that the average gas mileage of a particular car will vary depending on the person who is driving the car due to different driving styles. Because of this, he decides to use a randomized block design. He randomly selects five drivers and asks them to drive each of the cars. He then determines the average gas mileage for each car and each driver. Can the dealer conclude that there is a significant difference in average gas mileages of the four car models? The results of the study are as follows.  Average Gas Mileage Driver Car A Car B Car C Car D Driver 1 3636 3636 3535 2929 Driver 2 2525 3737 3737 3838 Driver 3 2323 3939 2525 3636 Driver 4 2121 3838 3939 2727 Driver 5 2424 3434 3636 3030 Copy Data ANOVA Source of Variation SSSS dfdf MSMS Rows 47.500047.5000 44 11.875011.8750 Columns 334.9500334.9500 33 111.6500111.6500 Error 315.3000315.3000…