Question

A random sample of university students were asked whether they participate in varsity athletics and how many times they had used marijuana in the last ten days. If the necessary conditions are met, which of the following methods would be most appropriate to test for an association between the whether or not a student participates in varsity athletics and the frequency of marijuana use? A) One sample t-test B) Paired t-test C) Two sample t-test for difference in means D) ANOVA A O c O D A researcher is planning a studyto compare the mean IQ between people who are left-handed and people who are right-handed. The researcher will use data from a sample to calculate a 95% confidence interval for the difference in means. The researcher has estimated that the standard deviation of IQ in both groups will be approximately 15 and that approximately 90% of the people in the sample will be right handed. Based on these assumptions, the researcher has determined that a total sample of size of 400 people is needed in order to have a 5 point margin of error. If all of the assumptions were correct but the data are used to make a 99% confidence interval (instead of a 95% confidence interval) which of the following would be true? A. The sample of 400 would give a margin of error smaller than 5. B. The sample of 400 would give a margin of error larger than 5. c. The sample of 400 will still give a margin of error equal to 5. D. There is no way of figuring out how the margin of error might change. A company designed a new running shoe that they believe will increase a person's running speed. Fifty runners each complete two 1000 meter time trials; once while wearing their usual running shoe and once while wearing the new running shoe. (Which shoe was worn in the first time trial was decided by flipping a coin.) If the necessary conditions are met, which of the following methods would be most appropriate to test to determine whether there people run faster? A) One sample t-test evidence that the new shoe makes B) Paired t-test C) Two sample t-test for difference means D) ANOVA

Answer 1

Paird t test. Option B is correct.

The sample of 400 would give a margin of error smaller than 5. Option A is correct.

Two sample t tesg for difference in means. Option C is correct