Question

a.A seven-year medical research study reported that woman whose mothers took the drug DES during pregnancy were twice as likely to develop tissue abnormalities that might lead to cancer as were women whose mothers did not take the drug.b. Do you suppose the data were obtained in a survey or an experimentc. For the population of women whose mothers took the drug DES during pregnancy, a sample of 3980 women showed that 63 developed tissue abnormalities that might lead to cancer. Provide a descriptive statistic that could be used to estimate the number of women out of 1000 in this population who have tissue abnormalities.d. For the population of woman whose mothers did not take the drug DES during pregnancy, what is the estimate of the number of women out of 1000 who would be expected to have tissue abnormalities?e. Medical studies often use a relatively large sample (in this case, 3980) why?

Answer 1

Explanation:

b. An experiment deliberately imposes some stimuli on individuals to observe their responses whereas a survey aims to gather information without affecting the individuals.

Hence, the data was obtained in a SURVEY as the consumption of drug was not forced.

c. Given Data:

x = 63

n = 3980

The probability will be the number of successes divided by the sample size:

`p\;=\;(x)/(n) =(63)/(3980) \\\\p\;=\;0.0158`

The total number of successes is the product of the sample size and the probability of occurrence of tissue abnormalities.

`x\;=\;n*p\;=\;1000*0.0158\\\\x\;=\;15.8`

d. As we have no data pertaining to the population of women who did not take the drug, we cannot make estimate about the number of women that will have abnormalities.

e. Larger values of sample reduces the effect that outliers can cause on the skewness of the data. As a result the interpretations are more reliable. Hence, use of large sample sizes is necessary because people's lives could be at stake.