Ch. 4 Practice Problems 11, 14, & 18
11. List the five steps of hypothesis testing, and explain the procedure and logic of each.
The first step in testing hypotheses is to take the question at hand and turn it into a pair of theories that can be tested; the question is stated as a research hypothesis, and as a null hypothesis about the populations to be studied. The purpose behind this is to establish something to test the research hypothesis against, and essentially proving that the opposite of something is false is the same as proving that the thing is right. A prediction is made and then the polar opposite of the prediction is studied to ascertain its validity. If the null is proved wrong then the research hypothesis testing…show more content… A researcher predicts that listening to music while solving math problems will make a particular area of the brain more active. To test this, a research participant has her brain scanned while listening to music and solving math problems, and the brain area of interest has a percentage signal change of 58. From many previous studies with the same math problems procedure (but not listening to music), it is known that the signal change in this brain area is normally distributed with a mean of 35 and a standard deviation of 10. (a) Using the .01 level, what should the researchers conclude? Solve this problem explicitly using all five steps of hypothesis testing, and illustrate your answers with a sketch showing the comparison distribution, the cutoff (or cutoffs), and the score of the sample on this distribution. (b) Then explain your answer to someone who has never had a course in statistics (but who is familiar with mean, standard deviation, and Z scores). The hypothesis testing process begins by forming a question about the topic at hand. In this case, “Does listening to music while doing math stimulate a certain region of the brain that is not affected when doing math without music?” This question is then turned into a pair of