1) A comparison of means focuses on the difference between two population or treatment means, ?1 − ?2. When testing the hypothesis ?0: ?1 − ?2 = 0, there are three possible alternative hypotheses. (a)...

Finish all questions.


1) A comparison of means focuses on the difference between two population or treatment means, ?1 − ?2. When testing the hypothesis ?0: ?1 − ?2 = 0, there are three possible alternative hypotheses. (a) Using correct statistical notation, list the three possible alternative hypotheses. (b) For each alternative hypothesis in part (a), give an example of a situation from your own experience or your reading where one might use that alternative hypothesis. Be sure to clearly specify a context, define your variables, and state the null and alternative hypothesis. Use three different contexts. 2a) When testing hypotheses about, and constructing confidence intervals for ?1 − ?2, using independent samples, we use the statistic, ?̅1 − ?̅2. What are the mean and standard deviation of the sampling distribution of , ?̅1 − ?̅2? 3) A researcher is testing the effectiveness of two vaccines for preventing a disease. Two randomly selected treatment groups are chosen. 200 people were given vaccine A and 300 people were given vaccine B. During the trial period, 80 people who were given vaccine A and 105 people who were given vaccine B subsequently came down with the disease. Is vaccine B more effective than vaccine A? Use ? = 0.05. Your answer should show assumptions, hypotheses, and conclusions. 4) For your initial post, explain the differences between between paired samples and independent samples.  Then  explain how we conduct hypothesis tests for paired samples and independent samples.