ANCOVA in SPSS
To improve retention and graduation rates, the Developmental Studies Committee of Sussex Junior College (SJC), directs the Remedial Reading Department to offer special non-credit developmental (remedial) reading classes for under-prepared first-time, full-time, college freshmen. SJC has been offering non-credit remedial reading classes (aka Developmental Reading Instruction) for the past thirty years as an attempt to elevate under-prepared students reading levels to meet the demands of college-level classes. But like most open-enrollment community colleges throughout the country, these remedial classes have little impact on improving students reading comprehension levels or their retention or persistence in college. Consequently, most SJC Developmental Students drop-out of college in the first year. The new SJC program, named the College-Success Program, differs from traditional developmental reading classes in that students start receiving basic remedial reading instruction in mid-summer, four weeks prior to the start of the Fall semester.
Asked to assess the effectiveness of the College Success Program, SJC’s Director on Institutional Research, Andy Wald, designs a study to compare the total number of credits completed during the first year of college (fall + spring semesters) for a random sample of College Success Students, (n = 10), a random sample of traditional Developmental Reading Students (n = 10), and random sample of Non-Developmental Students (n = 10) – students whose reading comprehension levels are at college-level, and were not required to enroll in developmental reading classes.
Director Wald also collects student scores on the CTP-Reading Comprehension test (CPT-R) – the test that SJC uses to assess the reading comprehension levels, and to place students into developmental or traditional college-level classes during their 1st semester. This data is collected to rule-out the possibility that the reading comprehension levels of students selected to participate in the newly created College Success Program may differ significantly from their traditional Developmental Student counterparts.
The sample of Non-Developmental students was included in the study to determine if College Success Students would complete annual credits comparable to traditional non-developmental college students.
Using the attached SPSS data file, conduct an ANCOVA in which Credits is the DV, Group (College Success, Developmental, or Non-Developmental) is the IV, and CPT-R is the covariate (CV). In correct APA Style, fully summarize the goals, results, and conclusion that can be drawn from the study. Be sure to include the appropriate Tables and Figures in the summary.
Here are the required elements of the Week 8 Application Assignment.
1) Write a Null and Alternative Hypothesis specific to the research question.
2) Explain the goals of the study and of the analyses.
3) (Optional, not part of the grade rubric) Describe the sample.
4) (Optional, not part of the grade rubric) Test the assumptions of ANCOVA (hint, Levene’s test for the between group factor, and the test for homogeneity of regression) – report the results of these tests to determine if the data meets the assumptions of ANCOVA. Summarize your findings in correct APA format. See my sample summary.
5) Within your summary include a correctly formatted (APA Style) table. Within the table report group means, 95% CI for means, SDs, SE, adjusted means. Be sure to refer to the table within the summary.
6) Plot the adjusted means. Be sure to refer to the figure within the summary.
7) Create an APA formatted table of the ANCOVA Results. Be sure to refer to the table within the summary.
8) Fully summarize the results for the ANCOVA in correct APA style. Be sure to report and interpret the results for the covariate (CPT-R) and for the between groups factor. Be sure to report and interpret the appropriate effect sizes. And, be sure to report the type of post hoc test conducted, and the results from (Bonferroni’s) the post hoc mean comparison tests.
9) Be sure to explain what conclusions can be drawn from the study?
10) Attach the SPSS output in an appendix to your paper.
