Question

One Management professor adopted a crossword puzzle exercise in his introductory management information systems (MIS) class, because he believes that the most important effects of engaging in a crossword exercise is the great workout it gives one's brain—solving crossword puzzles requires several skills, such as spelling, reasoning, making inferences, evaluating choices, and drawing conclusions. That is, the exercise may enhance one's ability to memorize words. He wants to know whether or not the crossword puzzle exercise can accelerate the learning of MIS vocabulary and terms. A total of 109 students in his two sections of a MIS class in fall 2009 participated in an experiment involving student learning and retention of MIS terms using the crossword puzzle exercise. One section (56 students) was defined as a control group, while the other section (53 students) was defined as an experimental group. One day about two weeks before the end of semester, students in the control group were given a list of terms taken from the text book used in the course; students in the experimental group were given a crossword puzzle exercise containing terms and phrases taken from the same text book and based on the same list of terms given to the control group. Before an in-class quiz, both groups had forty minutes to use their handouts to prepare; after forty minutes, both groups were given the same quiz. To ensure that experimental subjects worked the crossword puzzle, they had to submit a complete puzzle to the professor prior to the quiz. After the quiz, the professor computed the proportion of students who received A and B grades of the quiz for these two groups. If the proportion of A and B grades is significantly high, it implies that the crossword puzzle exercise may accelerate student learning. The proportion of the experimental group is 0.7547, while the proportion of the control group is 0.6429. He then developed a two-tailed test. The null hypothesis is: the proportion of A and B grades in the experimental group that used the crossword puzzle handout as an aid in studying for their quiz is not different from the proportion of A and B grades in the control group that did not have that handout. The alternative hypothesis is: the proportion of A and B grades in the experimental group that used the crossword puzzle handout as an aid in studying for their quiz is different from the proportion of A and B grades in the control group that did not have that handout. Since he did not have any further information about the population, he used t test statistic. Did the professor develop a correct hypothesis test and use a correct test statistic? If you think yes, explain why you think yes; if no, explain why not and how to develop a correct hypothesis test.

Answer 1

>> the professor develop a correct hypothesis test

>> Let p1 be the proportion of students getting A and B grades in experimental group and p2 be the proportion of students getting A and B grades in the control group.

>> Ho: p1 - p2 =0

Ha: p1 - p2 not = 0

>> the t statistics is used is not correct. he should used the z statictics

>> n1 =53, n2= 56, p1 = 0.7547 , p2 =  0.6429

>> Z-statistisc = {( p1 - p2 ) - 0} / sqrt ( p( 1 - p) / {1/n1 + 1/ n2} )

Where p = ( p1n1 + p2n2 ) / (n1 + n2)