A study of wolf spiders by Persons and Uetz, published in the online journal Animal Behavior in November 2004, reports that, "of the 120 virgin females paired with males, 87 attempted cannibalism by lunging repeatedly at the male. Ten of these attempts at premating cannibalism were successful."42 For the following, round your answers to the nearest thousandth (three decimal places).
a. Find the sample proportion that attempted cannibalism.
b. What is the approximate standard deviation of sample proportion that attempted cannibalism?
c. Report a 95% confidence interval for population proportion, if we are interested in the proportion of all virgin female wolf spiders that would attempt cannibalism.
d. Of the 120 females observed, find the sample proportion that succeeded at cannibalism.
e. What is the approximate standard deviation of sample proportion in part (d)?
f. Report a 95% confidence interval for population proportion, if we are interested in the proportion of all virgin female wolf spiders that would attempt cannibalism and succeed.
g. In general, is a confidence interval for a given sample size wider or narrower for sample proportions that are farther from 0.5?
h. Of the 87 females that attempted cannibalism, find the sample proportion that succeeded.
i. What is the approximate standard deviation of the sample proportion in part (h)?
j. Report a 95% confidence interval for the population proportion, if we are interested in the proportion that succeed, given that a virgin female wolf spider has attempted cannibalism.