At one vehicle inspection station, 13 of 52 trucks and 11 of…
At one vehicle inspection station, 13 of 52 trucks and 11 of 88 cars failed the emissions test. Assuming these vehicles were representative of the cars and trucks in that area, what is the standard error of the difference in the percentages of all cars and trucks that are not in compliance with air quality regulations?
Read DetailsTruckers On many highways state police officers conduct insp…
Truckers On many highways state police officers conduct inspections of driving logbooks from large trucks to see if the trucker has driven too many hours in a day. At one truck inspection station they issued citations to 49 of 348 truckers that they reviewed. a. Based on the results of this inspection station, construct and interpret a 95% confidence interval for the proportion of truck drivers that have driven too many hours in a day. b. Explain the meaning of “95% confidence” in part A.
Read DetailsWe are about to test a hypothesis using data from a well-des…
We are about to test a hypothesis using data from a well-designed study. Which is true?I. A small P-value would be strong evidence against the null hypothesis.II. We can set a higher standard of proof by choosing = 10% instead of 5%.III. If we reduce the alpha level, we reduce the power of the test.
Read DetailsDolphin births A state has two aquariums that have dolphins,…
Dolphin births A state has two aquariums that have dolphins, with more births recorded at the larger aquarium than at the smaller one. Records indicate that in general babies are equally likely to be male or female, but the gender ratio varies from season to season. Which aquarium is more likely to report a season when over two-thirds of the dolphins born were males? Explain.
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