PSYC 3290 - LAB ASSIGNMENT 3 - ANOVA 1

PSYC 3290 – ANOVA 1 DUE DATE : October 25 (Wednesday lab) and October 27 (Friday lab), 11:59 PM submitted as a .pdf document in Courselink. Please refer to the course outline regarding course policies and procedures regarding lab assignment submissions. HOMEWORK QUESTION The Beck Depression Inventory (BDI) is a 21-item, self-report rating inventory that measures characteristic attitudes and symptoms of depression (Beck, et al., 1961). Created by Dr. Aaron T. Beck, it is a 21- question multiple-choice self-report inventory and is one of the most widely used instruments for measuring the severity of depression. The possible score of the BDI ranges from 0 (no depression) to 63 (severe depression). A clinical health care facility on a university campus sought to determine if depression among university students varied by year of study. The clinic obtained sample of 15 students in each of four different years of study: 1 st , 2 nd , 3 rd , and 4 th year (N=60), and evaluated these research participants for their depression as measured by the BDI. The raw data are depicted below. 1 st year BDI 2 nd year BDI 3 rd year BDI 4 th year BDI 19 18 16 25 22 28 22 31 31 32 31 38 41 44 36 46 27 15 17 26 21 16 20 28 28 32 27 39 32 41 44 47 39 36 31 51 12 14 12 44 18 17 15 37 22 25 23 33 25 29 26 29 33 38 32 40 15 30 34 39 Based upon these data, would you conclude that depression is different between years of study, and if so, what is the pattern? LAB REPORT INSTRUCTIONS/DIRECTIONS: 1) Title page including: student name, number, course code and title, date, and title of assignment.

2) Compute the descriptive statistics for each of the 4 years of data, as outlined in the table below. 3) Perform a single-factor ANOVA making sure to state the null and alternative hypotheses (use the alpha level of 0.05). If necessary, perform a Tukey HSD post-hoc procedure. 4) Generate a plot of the results. 5) In one paragraph (approximately half page, double-spaced), state your conclusions regarding the analysis. 6) Include the RStudio script that you used to analyze the data. Perform the statistical calculations using RStudio and present the results in table(s). Typically, tables do not include vertical bars so those should be omitted. Note that when presenting the results of a statistical analysis and generating a report, there will always be some variability in doing so between people. The important aspect is that the key elements of the statistical analysis, data presentation, and data interpretation/conclusions are presented clearly and effectively.  Beck, A.T., Ward, C. H., Mendelson, M., Mock, J., & Erbaugh, J. (1961) An inventory for measuring depression. Archives of General Psychiatry, 4 , 561-571.  Osman, A., Kopper, B.A., Barrios, F., Gutierrez, P.M., & Bagge, C.L. (2004). Reliability and validity of the Beck Depression Inventory-II with adolescent psychiatric inpatients. Psychological Assessment, 16(2), 120-132. 2

DESCRIPTIVE STATISTICS (N=60) Mean Standard deviation Standard error Skewness Kurto sis 1 st year 2 nd year 3 rd year 4 th year NULL AND ALTERNATIVE HYPOTHESES: Rejection/retain rule: 4

ANOVA TABLE AND STATISTICAL TESTING GRAPH CONCLUSIONS APPENDICES Include the RStudio script OR a screen capture of the analysis in MS EXCEL or SPSS. IMPORTANT: For your screen captured images, you MUST title your file that appears along the top with your full name. Points for this section will NOT be provided if your name does not appear at the top or somewhere in the image. When downloading the MS EXCEL file of data, you should SAVE AS the file and rename it with your name. 5