Professor Romano looks at ways to improve student learning. She gives half of her students practice quizzes with only multiple choice questions. She gives the other half of her students practice quizzes that also include short answer questions. Then she looks at how students perform on the exam. Which of the following would be a NOISE variable?Group of answer choicesIf a student already makes their own short answer questions to practice their understandingThe students in the short answer group have a higher average already (before the exam) than the students in the multiple choice groupAll of the students are in the same class sectionWhat type of quiz questions the students saw

To determine whether noise affects the ability to solve math problems, a researcher has one group solve math problems in a quiet room and another group solve math problems in a noisy room. The group solving problems in the noisy room completes 25 problems in one hour and the group solving problems in the quiet room completes 34 problems in one hour. In this experiment, the independent variable is ____________ and the dependent variable is _____________. A. The number of problems solves; the difficulty of the problems. B. The number of problems solved; the noise level in the room. C. The noise level in the room; the number of problems solved. D. The noise level in the room; the difficulty of the problems.

30 randomly selected statistics students were first given 20 multiple-choice questions and then 20 open-ended questions – all on the same material. The lecturer was interested in determining which type of questions the students scored higher, on average. This experiment is an example of ______. a. a test of variances b. a two sample test of means c. a paired t test d. a two sample test of proportions

(a) [4 marks] A student answers a multiple-choice examination question that offersfour possible answers. Suppose that the probability that he knows the answer tothe question is 0.8 and the probability that he guesses is 0.2. Assume that if thestudent guesses, the probability of selecting the correct answer is 0.25. If the studentcorrectly answers a question, find the probability that he really knew the correctanswer.(b) [5 marks] Suppose the student takes an examination with 3 multiple choice ques-tions. Let X denote the number of questions he gets correct. Assuming that thestudent answers each question independently, determine the probability distributionof X and calculate the expected value of X.(c) [10 marks] Suppose the student takes an examination with 2 multiple choice ques-tions. But this time, he gains confidence every time he knows the answer to a ques-tion. Specifically, if he knows the answer to the current question, then for the nextquestion the probability that he knows the answer becomes 0.9 and the probabilitythat he guesses becomes 0.1. If he does not know the answer to the current ques-tion, then for the next question the probability that he knows the answer and theprobability that he guesses remain 0.8 and 0.2, respectively. Again letting X denotethe number of questions he gets correct, determine the probability distribution of Xand calculate the expected value of X. We can assume the probabilities of knowingthe answer and guessing for the first question are 0.8 and 0.2, respectively.

Two quizzes were administered to the class. There were no absentees on both days when the quizzes were administered. In Quiz 1. the ratio of passes to failures is 3:1. In Quiz 2, the ratio of passes to failures is 4:1. If the number of failures in Quiz 2 is one less than that in Quiz 1. how many students are in the class?

In a basic true experiment with only two conditions, you are interested in the effects of noise on completing a comprehension task. You decide to play a tape recording of very loud music to which group of participants? A. Those participants in the control condition. B. Those participants in the experimental condition. C. Those participants in another random group. D. None of these. It is a trick question