Inferential Statistics in Psychology — DU Psychology Honours Previous Year Question Papers

Q1. Dr. Gupta invented a new drug that he believes cures diabetes. To test the effectiveness of the drug, she randomly selected 64 participants and administered the drug on them. The average score for the sample chosen by Dr Gupta is X = 54. Prior studies indicate the mean effectiveness of all the diabetes drugs is 50 (4 = 50) and the standard deviation (o) is 15 . What can Dr. Gupta conclude? Use a one-tailed test at the .05 level of significance and help him to make a correct interpretation. (b) A sociology student, Rohan, is investigating the study habits of students at his college. Rohan believes that, on average, students spend 10 hours per week studying in the campus library. He collects data from a random sample of 5 students over the course of a semester. The average weekly library hours for these students are as 7, 6, 8, 5, 6. State formally Ho and Ha (non-directional). By ca culating t (a= .05) examine is there any evidence to suggest that Rohan's's belief is incorrect? (10) (10) Q2. A researcher is interested in testing employment status differences in subjective well-being. The participants achieved the following scores: State formally the hypotheses necessary to conduct a non-directional test of no difference. Complete the test at 0.01 level of significance and state your conclusion. 03. A researcher conducted a study to examine the effectiveness of music therapy. He believes that music will definitely improve emotional well-being. He took a sample of 36 participants and compared their emotional well-being scores before and after a session of music therapy. The data is given below (r = +0.63). (15) Before Therapy (X) After Therapy (X) Mean sX Mean sy i) State formally the hypotheses best suited to the nature of inquiry of the researcher. Complete the test at 0.01 level of significance and state your conclusion. ili) Construct a confidence interval of ux - ur according to 0.95. 04. A professor wants to study problem-solving ability across three academic streams. She randomly selected 4 students from each stream: Science. Commerce and Humanities. Following are the scores by three group of subjects: Express Ho and Ha. By calculating F ratio (a= .05) examine whether different streams of education have different effects on the problem solving ability of the subjects. (15) (15) Q5. A researcher is interested in whether there is a significant association between a student's chosen major and their primary source for news. A sample of 180 students from three different departments: Engineering, Law, and Fine Arts—were asked if they primarily get their news from Social Media or Traditional News Outlet (TV/Newspapers). The observed frequencies are recorded in the table below: Engineering Law Fine Art Social Media 24 66 10 Traditional News Outlet 37 66 17 State the null hypothesis of independence for this situation. Compute chi-square (a= .01) and draw final conclusions. (15)