I need help with these questions in homework. I also want to revise to make sure that they are correct /. In a study at West Virginia University Hospital, researchers investigated smoking behavior of cancer patients to make a program to help patients stop smoking. They published the results in Smoking Behaviors Among Cancer Survivors (January 2009 issue of the Journal of Oncology Practice.) In this study, the researchers sent a 22-item survey to 1,000 cancer patients. They collected demographic information (age, sex, ethnicity, zip code, level of education), clinical and smoking history, and information about quitting smoking.
The questionnaire filled out by cancer patients at West Virginia University Hospital also asked patients if they were current smokers. The current smoker rate for female cancer patients was 11.6%. 95 female respondents were included in the analysis. For male cancer patients, the current smoker rate was 10.4%, and 67 male respondents were included in the analysis. Suppose that these current smoker rates are the true parameters for all cancer patients. Can we use a normal model for the sampling distribution of differences in proportions?
a. No, a normal model is not a good fit for this sampling distribution.
b. Yes, a normal model is a good fit for this sampling distribution.
Figure A represents the weights for a sample of 26 pebbles, each weighed to the nearest gram.
Figure B represents the mean weights of a random sample of 3 pebbles each, with the mean weights rounded to the nearest gram.
One value is circled in each distribution. What is the difference between what is represented by the X circled in A and the X circled in B?
Please select the best answer from the list below.
a. Figure A has a larger range of values than Figure B.
b. The X in Figure A is the weight for a single pebble, while the X in Figure B represents the average weight of 3 pebbles.
c. There is no difference since in both Figure A and Figure B, the X represents one pebble that weighs 6 grams.
A nutritional scientist is investigating the effects of ketogenic dieting on lean body mass. They studied 50 college age men in a paired study: each pair matched on starting lean body mass, height, and race and divided into Groups A and B. Group A consumed a ketogenic diet while Group B consumed a traditional western diet.
Which type of hypothesis test should they use?
a. test for one population proportion
b. test for one population mean
c. test for a difference in two population proportions
d. test for a difference in two population means
Researchers created a new fertilizer. They conducted an experiment to compare the new fertilizer to the old fertilizer. They divided tomato plants into two groups. They applied the new fertilizer to one group and the old fertilizer to another group. The variable is the number of tomatoes per plant on a randomly selected day.
Which one of the following statements is valid?
a. The new formula of fertilizer works better. Plants with the new fertilizer had more tomatoes.
b. The average number of tomatoes per plant with the old fertilizer is higher than the average amount of tomatoes per plant with the new fertilizer.
c. We can make no conclusions from this data about which fertilizer is better because the two groups have a different number of plants.
d. The old formula of fertilizer was better because the plant with the most tomatoes was treated with the old fertilizer.
Quit Smoking: The New England Journal of Medicine published the results of a double-blind, placebo-controlled experiment to study the effect of nicotine patches and the antidepressant bupropion on quitting smoking.
With the data from the experiment we calculate the sample difference in the "quit smoking" rates for the nicotine treatment group and the placebo group ("treatment" minus "placebo"). We get 0.8% = 0.008. Which of the following is an appropriate conclusion based on this finding?
a. Nicotine patches and the antidepressant bupropion work equally well on "quit smoking" rates.
b. Nicotine patches will produce a slightly higher success rate when compared to a placebo, but the difference is not statistically significant.
c. In this experiment, the placebo group had a higher success rate than the nicotine group by 0.8%.
d. In this experiment the nicotine treatment had a higher success rate than the placebo group, but the improvement was less than 1%.
1) Option b) Yes, a normal model is a good fit for this sampling distribution. 2) Figures are missing so it cannot be... View the full answer