Question

In: Statistics and Probability

A randomized study was performed to determine whether a diet of processed meats causes a higher...

A randomized study was performed to determine whether a diet of processed meats causes a higher proportion of incidents of breast cancer. Researchers compared high intake versus low intake diets of processed meats for women with breast cancer and found the following results shown in the two-way table below:

Breast Cancer

No Breast Cancer

Total

High Intake processed meat

88

152

240

Low Intake processed meat

61

159

220

  1. Using phigh for the proportion with diet high in processed meat who got breast cancer and plow for the proportion of women with diet low in processed meat who got breast cancer, compute the appropriate sample statistic for this difference of proportions. Show notation and the calculation.
  2. Use STATKEY with bootstrapping to create 10,000 generated samples. Use the STATKEY output to find the 95% confidence interval. Then sketch the curve (no details) for what you see in the STATKEY output. Be sure to write the lower and upper bound values on your curve.
  3. Interpret these results in context of the problem.
  4. Now formulate the null and alternative hypotheses to determine whether there is a difference in proportions for women to get breast cancer depending on high or low intake of processed meats.

Solutions

Expert Solution

(a) phigh = 88/240 = 0.37

plow = 61/220 = 0.28

p = 0.37*240 + 0.28*220/(240 + 220) = 0.32

(b) The STATKEY output is:

The curve is:

The 95% confidence interval for the difference of proportions is between 0.0933 and 0.2559.

(c) We are 95% confident that the true difference of proportions is between 0.0933 and 0.2559.

(d) The hypothesis being tested is:

H0: p1 = p2

Ha: p1 ≠ p2


Related Solutions

A study is performed in a small town to determine whether the average weekly grocery bill...
A study is performed in a small town to determine whether the average weekly grocery bill for a four-person family is significantly less than national average of $185. A simple random sample of 19 weekly grocery bills for four-person families is selected from the town. The data is shown to the right. They suspect from the sample data that the small town's average grocery bill is less than the national average. That is, they want to test the hypotheses: Ho:...
A study is performed in a large southern town to determine whether the average amount spent...
A study is performed in a large southern town to determine whether the average amount spent on fod per four person family in the town is significantly different from the national average. Assume the national average amount spent on food for a four- person family is $150. A what is the null and alternative hypothesis? b. Is the sample evidence significant? significance level? Family Weekly food expense 1 $198.23 2 $143.53 3 $207.48 4 $134.55 5 $182.01 6 $189.84 7...
6. A randomized block analysis was performed to examine whether the color of an energy drink...
6. A randomized block analysis was performed to examine whether the color of an energy drink (e.g., red, green, blue, purple) has an effect on the sales of the energy drink. Because the type of store (e.g., convenience, grocery, and discount) where the drink is sold could have an effect on sales the analyst decided to control for store differences by blocking on stores (the analyst believes the stores could be a nuisance in the analysis). Three blocks were used...
A case-control study was performed to determine whether head injury was associated with an increased risk...
A case-control study was performed to determine whether head injury was associated with an increased risk of brain tumors in children. 200 cases with brain cancer were identified from the state cancer registry and 200 controls were recruited from the same neighborhoods where the cases lived. The mothers of the children completed a questionnaire that asked them to describe their child's past history of head injury. The investigators found that the mothers of the children with brain tumors reported a...
A recent study found that toddlers who have a diet high in processed foods may have...
A recent study found that toddlers who have a diet high in processed foods may have a slightly lower IQ later in life. The conclusion came from a long-term investigation of 14,000 people whose health was monitored at 3,4,7, and 8 years of age. e) One analysis found that of the 4000 children for which there were complete data, there was a significant difference in IQ between those who had had “processed” (i.e., junk) food and those who followed health-conscious...
select the experiments that use a randomized comparative design. Participants in a study to determine the...
select the experiments that use a randomized comparative design. Participants in a study to determine the effects of a new blood pressure drug are divided into groups based on body mass index. All overweight participants receive the new drug, and all normal or underweight participants receive a currently approved drug. Environmental scientists are concerned with the effects of nitrogen on the drinking water supply. Hundreds of farmers have volunteered to participate in the study in exchange for free fertilizer. The...
The objective of a randomized controlled trial by Adab et al. (A-19) was to determine whether...
The objective of a randomized controlled trial by Adab et al. (A-19) was to determine whether providing women with additional information on the pros and cons of screening for cervical cancer would increase the willingness to be screened. A treatment group of 138 women received a leaflet on screening that contained more information (average individual risk for cervical cancer, likelihood of positive finding, the possibility of false positive/negative results, etc.) than the standard leaflet developed by the British National Health...
The objective of a randomized controlled trial by Adab et al. (A-19) was to determine whether...
The objective of a randomized controlled trial by Adab et al. (A-19) was to determine whether providing women with additional information on the pros and cons of screening for cervical cancer would increase the willingness to be screened. A treatment group of 138 women received a leaflet on screening that contained more information (average individual risk for cervical cancer, likelihood of positive finding, the possibility of false positive/negative results, etc.) than the standard leaflet developed by the British National Health...
A study was performed to examine whether the type of gasoline used is independent of a...
A study was performed to examine whether the type of gasoline used is independent of a person's living status. The researcher surveyed 600 people and asked two questions. The first question asked was “Do you use regular, plus, or super gasoline when filling up?” The second question asked was “Do you rent or own your place of residence?” The results are shown below. Assume the significance level α = .05 is used for the test. Type of Gas Living Status...
A study was conducted to determine the effectiveness of a diet program in reducing weight of...
A study was conducted to determine the effectiveness of a diet program in reducing weight of obeys people. Eight randomly selected patients were put on this diet and the amount of weight losses (in pounds) were recorded. Suppose the sample mean and the sample standard deviation of weight losses were 38 and 4.598136 pounds, respectively. Construct a 90% confidence interval for the average weight loss and based on the confidence interval constructed determine if you would expect to see an...
ADVERTISEMENT
ADVERTISEMENT
ADVERTISEMENT