Better Traffic Flow introduces the dataset TrafficFlow, which gives delay time in seconds for 24 simulation runs in Dresden, Ger
many, comparing the current timed traffic light system on each run to a proposed flexible traffic light system in which lights communicate traffic flow information to neighboring lights. On average, public transportation was delayed 105 seconds under the timed system and 44 seconds under the flexible system. Since this is a matched pairs experiment, we are interested in the difference in times between the two methods for each of the 24 simulations. For the n = 24 differences D. we saw that barXD = 61 seconds with SD = 15.19 seconds. We wish to estimate the aver- age time savings for public transportation on this stretch of road if the city of Dresden moves to the traffic light system on each run to a pr new system. A) What parameter are we estimating?
B) Suppose that we write the 24 differences on 24 slips of paper. Describe how to physi- cally use the paper slips to create a bootstrap sample.
C) What statistic do we record for this one boot- strap sample?
D) If we create a bootstrap distribution using many of these bootstrap statistics, what shape do we expect it to have and where do we expect it to be centered?
E) How can we use the values in the bootstrap dis- tribution to find the standard error?
F) The standard error is 3.1 for one set of 10,000 bootstrap samples. Find and interpret a 95% confidence interval for the average time savings.
