Math 105 Exam 4 with correct answers

Math 105 Exam 4 with correct answers Questions with Multichoices Suppose a confidence interval for the difference in mean weight loss for two different weight loss programs (Program 1 – Program 2) is entirely above zero. What does this mean? A. We can say with confidence that there is a difference in mean weight loss for the populations of people on these two programs; further, we can say that the average weight loss on Program 2 is higher. B. We can say with confidence that there is a difference in mean weight loss for the populations of people on these two programs; further, we can say that the average weight loss on Program 1 is higher. C. We can’t say with any confidence that there is a difference in mean weight loss for the populations of people on these two programs. D. none of the above C When a relationship or value from a sample is so strong that we decide to rule out chance as an explanation for its magnitude, what does this mean? A. We could have been unlucky with our sample, and come to the wrong conclusion, but that chance is small. B. The observed result is statistically significant. C. We conclude that the observed result carries over to the population and cannot be explained away by chance. D. all of the above D What numerical value do you calculate that gives you the answer to the question of how unlikely the test statistic would be if the null hypothesis were true? A. Type II error B. confidence level C. Type I error D. p-value D Which of the following is true when a Type I error has been committed? A. The data must have convinced us that the alternative hypothesis was true. B. The probability of making a Type I error is equal to the stated level of significance, usually 0.05. C. The null hypothesis has to have been true. D. all of the above D Which of the following describes the power of a test? A. Bigger samples result in more power for the test, and smaller samples result in less power for the test. B. It is the probability of making the correct decision when the alternative hypothesis is true. C. It is higher when the population value is farther from the value in the null hypothesis. D. all of the above D Even when information in a news article is sparse, you can sometimes piece the information together to figure out certain parts of the hypothesis test on your own. What piece of information is not possible to figure out unless it is given to you? A. the null and alternative hypotheses B. the impact of the conclusions C. the p-value or the test statistic D. all of the above D Suppose the p-value for your hypothesis test for a difference of two means was 0.001. Which of the following is an appropriate conclusion? A. If there really was no difference in the population means, we would see results as extreme as these only 0.1% of the time. B. You conclude that there is a statistically significant difference between the population means. C. You reject the null hypothesis. D. all of the above D What does a p-value from a hypothesis test not tell you? A. how extreme the observed difference or relationship was B. the direction of the difference or relationship (if one exists) C. how likely it is to have observed these particular results (or more extreme ones) given that the null hypothesis is true D. whether or not your results are statistically significant B Even if researchers used an extremely sophisticated statistical analysis from a complicated hypothesis test and study, there is one piece of information that you’ll always be able to interpret and understand. What is that piece of information? A. the test statistic B. the p-value C. the design of the study/experiment D. none of the abov