In: Statistics and Probability
Ants on a Sandwich How many ants will climb on a piece of a peanut butter sandwich left on the ground near an ant hill? To study this, a student in Australia left a piece of a sandwich for several minutes, then covered it with a jar and counted the number of ants. He did this eight times, and the results are shown in Table 3.10. (In fact, he also conducted an experiment to see if there is a difference in number of ants based on the sandwich filling. The details of that experiment are given in Chapter 8, and the full dataset is in SandwichAnts.)42
Table3.10 Number of ants on a sandwich Number of ants 43 59 22 25 36 47 19 21
(a) Find the mean and standard deviation of the sample.
(b) Describe how we could use eight slips of paper to create one bootstrap statistic. Be specific.
(c) What do we expect to be the shape and center of the bootstrap distribution?
(d) What is the population parameter of interest? What is the best estimate for that parameter?
(e) A bootstrap distribution of 5000 bootstrap statistics gives a standard error of 4.85. Use the standard error to find and interpret a 95% confidence interval for the parameter defined in part (d).