Analysis of Variance With Repeated Measures
By now you are most likely comfortable with the concept of one-way and multi-way ANOVA, yet you have only been exposed to data that are independent. Many research scenarios wish to test for a difference in means across time. For example, imagine an experiment where you subject a group of the same subjects to a different stimulus at different time points. Alternately, your Instructor may wish to examine the class’ mean level of statistics anxiety at the beginning, middle, and end of the course.
Because you are measuring the same subjects over time, your data are dependent and therefore you need a statistical test that will take this dependency into consideration. You could run multiple paired sample t tests but that would not only be inefficient, it would introduce the possibility of a type I error. The repeated measures ANOVA allows you to compare three or more means on dependent data without using multiple t tests.
This week you practice using the repeated measures ANOVA and critique an article that uses this method
• Apply analysis of variance with repeated measures to a dataset
• Analyze analysis of variance with repeated measures in a dataset
• Apply statistical software to analyze data
• Critique research studies that apply analysis of variance with repeated measures
Assignment 1: Repeated Measures ANOVA in SPSS
Earlier this week, you practiced using repeated measures ANOVA models with SPSS and, ideally. In this Assignment, you apply what you learned to answer a social research question using Repeated Measures ANOVA.
To prepare
• Review the datasets provided.
• Construct a research question based on one of those datasets.
• Pay attention to the assumptions of this test, and ask, “Does it make sense to interpret the mean of this dependent variable?”
The Assignment
Use SPSS to answer the research question you constructed. Then, compose a 2 paragraph analysis in APA format in which you answer the following questions:
1. What is the null hypothesis for your question?
2. What research design(s) would align with this question?
3. What dependent variable was used and how is it measured?
4. What independent variable is used and how is it measured?
5. If you found significance, what is the strength of the effect?
6. What is the answer to your research question?
7. What are the possible implications of social change?
Be sure to include your data output with your analysis.
Name of Stats Test
Introduction
In a paragraph identify what statistical test you are doing, what data set you used, and what you are attempting to test using the variables you chose.
Research Question
Write your one sentence research question here. This should not be written as a question you can answer with a yes or no. Also, you will either use difference, effect, or relationship depending on the type of statistical test you are doing (see underlined word in RQ and hypotheses). You can also see that the independent variables (blue) are listed first and the dependent variable last (green)—do not use colors in your paper. Here is an example:
RQ: What is the relationship between the number of candy bars eaten in a day, hours spent exercising each week, and BMI?
Hypotheses
Null Hypothesis (H0): Write your null hypothesis here. You need to use the terminology “no statistically significant” in the null (see words in bold). You can also see that the independent variables (blue) are listed first and the dependent variable last (green)—do not use colors in your paper. Here is an example: There is no statistically significant relationship between the number of candy bars eaten in a day, hours spent exercising each week, and BMI.
Alternative Hypothesis (HA): Write your alternative hypothesis here. You need to use the terminology “statistically significant” in the alternative (see words in bold). You can also see that the independent variables (blue) are listed first and the dependent variable last (green)—do not use colors in your paper. Here is an example: There is a statistically significant relationship between the number of candy bars eaten in a day, hours spent exercising each week, and BMI.
Variables
Independent Variables (IV): List your independent variables here as well as how they are coded (values) in your dataset. For example:
Gender—Male=0; Female=1
Age—Actual age in years at time of data collection
Dependent Variables (DV): List your dependent variables here as well as how they are coded (values) in your dataset. For example:
Weight—Self-reported weight in pounds at time of data collection
Ever been a smoker—0=no; 1=yes
Results
Write your results section here. This should only be 1-3 paragraphs long—be succinct—but focus the results write up towards your null hypothesis and research question. Make sure that you address if the assumptions of the statistical test are met or not and what you did if they were not met and why. At the end of the results you should include if you are rejecting the null hypothesis and accepting the alternative (or retaining the null if that is appropriate) and why. Please see the examples posted in the announcements for an idea of what you results should look like and also look at the example below. ?
I highly recommend that you provide an APA formatted table to illustrate the results that you are discussing. It is difficult for the reader to follow the results if you just list a lot of numbers so use a table if the results are more complex than you can explain well in sentence format. However, make sure that the table is completely in APA format (see examples starting on p. 129 of the 6th ed. APA manual) as the tables that are generated by SPSS are not in APA format.
Here is an example of an APA formatted results section:
An ANCOVA was conducted to determine the effect of two different therapy approaches on stalking-type behavior after controlling for pre-therapy stalking-type behavior. There was homogeneity of regression slopes as the interaction term was not statistically significant, F(1,46) = .882, p = .353. The Levene’s test of homogeneity of covariances (F(1, 48) = 7.19, p = .01), was statistically significant and therefore the assumption was violated. The main effect of therapy approach was statistically significant, F(1, 47) = 5.49, p = .023, partial ?2 = .11, indicating that the hours spent in stalking-type behavior was lower after using the cognitive-behavioral therapy approach (M = 55.30, SE = 1.87) as compared to using the psychodynamic therapy approach (M = 61.50, SE = 1.87), as indicated in Table 1.
Table 1.
Therapy Approach Differences in Stalking-Type Behavior
*Table data here*
The covariate was statistically significant, F(1, 47) = 50.46, p < .05, partial ?2 = .52, indicating that amount of time spent in stalking-type behavior before therapy had a statistically significant effect on amount of time spent in stalking-type behavior after therapy. Therefore the null hypothesis is rejected and the alternative accepted. This means that the amount of time spent stalking before therapy should be considered when determining effectiveness of therapy on stalking behavior and the cognitive-behavioral therapy approach may be more effective in treating stalking behavior.
***Make sure to copy and paste your SPSS output (everything produced by SPSS at the end of the paper AFTER the reference list. There is a place at the end of the paper for you to paste this.
References
(Please note that the following references are just examples of APA formatting)
Alexander, G., & Bonaparte, N. (2008). My way or the highway that I built. Ancient Dictators, 25(7), 14-31. doi:10.8220/CTCE.52.1.23-91
Babar, E. (2007). The art of being a French elephant. Adventurous Cartoon Animals, 19, 4319-4392. Retrieved from https://www.elephants104.ace.org
Bumstead, D. (2009). The essentials: Sandwiches and sleep. Journals of Famous Loafers, 5, 565-582. doi:12.2847/CEDG.39.2.51-71
Hansel, G., & Gretel, D. (1973). Candied houses and unfriendly occupants. Thousand Oaks, CA: Fairy Tale Publishing.
Hera, J. (2008). Why Paris was wrong. Journal of Greek Goddess Sore Spots, 20(4), 19-21. doi: 15.555/GGE.64.1.76-82
Laureate Education, Inc. (Producer). (2007). How to cite a video: The city is always Baltimore [DVD]. Baltimore, MD: Author.
Laureate Education, Inc. (Producer). (2010). Name of program [Video webcast]. Retrieved from https://www.courseurl.com
Sinatra, F. (2008). Zing! Went the strings of my heart. Making Good Songs Great, 18(3), 31-22. Retrieved from https://articlesextollingrecordingsofyore.192/fs.com
Appendix: SPSS Output
Your SPSS Output file should be copied (Ctrl +A) and pasted here (Ctrl +V). Do not change your page layout to landscape. It is ok if it goes off the page on the right side.
Assignment 2: Article Critique
The practice of quantitative research not only involves statistical calculations and formulas but also involves the understanding of statistical techniques related to real-world applications. You might not become a quantitative researcher nor use statistical methods in your profession but as a consumer, citizen, and scholar-practitioner, it will be important for you to become a critical consumer of research, which will empower you to read, interpret, and evaluate the strength of claims made in scholarly material and daily news.
For this Assignment, you will critically evaluate a scholarly article related to repeated measures ANOVA.
The Assignment
Write a 2- to 3-page critique of the research you found which includes responses to the following prompts: The below headings should be in bold as headings.
• Why did the authors select repeated measures ANOVA in the research?
• Do you think this test was the most appropriate choice? Why or why not?
• Did the authors display the results in a figure or table?
• Does the results table stand alone? In other words, are you able to interpret the study from it? Why or why not?
Article Critique Assignment: Week #
Write the APA formatted reference of this article here. Make sure it is completely APA formatted. (Make sure you are using the article assigned for the week!!)
Introduction
Write a one paragraph summary of the article including why the research was done, what they found, and implications for social change (no more than 1 page).
Critique of Article/Research Study
In paragraph form, write a 2-3 page critique of the article you were assigned to read for the assignment. In this section you should consider the items asked in the directions for the assignment but do not copy and paste the questions into your paper and answer them one after another. A critique is not a summary (retelling) of the article and what the authors did. A critique is a combination of a short summary of what you are critiquing and then a critique of it (Was what they did appropriate? Why or why not? What would you have potentially done differently? Why? Did they follow best research practices? How do you know?).
Here are some of the things you should consider when critiquing a research article (do not just copy and paste these questions into the critique—this is just to give you an idea of what types of things to address—you don’t have to address everything but should have 2-3 pages of critique in this section—double spaced):
Critique of Literature Review
• Was the problem clearly articulated and was ample evidence provided to support the problem being addressed?
• Was the theoretical or conceptual framework present, was its relationship to the present study described, and was it appropriate to the problem being addressed?
• Was the literature cited appropriate to the topic?
• Was the literature primarily from current sources (within 5 years of the article publication date)?
• Did the author choose citations judiciously, or were did it appear that quantity of citations was emphasized over quality?
• Does the literature review present a clear and non-biased approach to the topic?
• Were the research questions and / or hypotheses clearly stated? Do they logically derive from the literature review?
Critique of Methods/Research Design
• Were the participants adequately described in terms of population, inclusion and exclusion criteria, and sampling strategy?
• Is the sample representative of the population?
• Is there support that the sample size ensures adequate statistical power?
• Was there a statement indicating that IRB approval was obtained?
• Were procedures for protecting participant rights included?
• Were the procedures for executing the design carefully described in a way that you or other scientists could replicate the study?
• Is the role and activity of the researcher in the data collection setting/sites described?
• Were reliability and validity measures of questionnaires, scales, or other measurement instruments presented? Do measures exhibit adequate reliability and validity?
• Were instruments used in populations for which they may not have been normed? Was there effort made to ensure reliability and validity in the study sample?
• Was the design appropriate to test the hypothesis(es) or address the research questions?
• Was random assignment used? If not, what are the potential flaws to internal and external validity?
Critique of Results Section
• Are the important characteristics of the sample described?
• Are participation rates (and attrition rates in longitudinal studies) described? For longitudinal studies, was differential attrition determined?
• Were key descriptive statistics provided for all variables?
• Do the results address the hypotheses under question?
• Are tables and figures used effectively? Were tables not used when they would have been very helpful to the reader?
• Are effect sizes and p-values reported for all inferential findings? Were they appropriate?
Critique of Discussion Section
• Are the results discussed in the context of the research presented in the literature review section?
• Are methodological limitations adequately addressed? Think in terms of sample representativeness, generalizability of results, and potential threats to internal and external validity.
• Are implications for further research described?
• Are implications for practitioners described?
• Is the contribution/significance to the field in relation to the continuum of inquiry clear?
You do not need to cite the article you are critiquing but you do need to cite any materials that you use in critiquing the article from other sources. If you do cite other resources you will need to add an APA formatted reference list on the last page of the paper.
Make sure that you are not giving non-human things human characteristics in your paper. This means things like “this study concluded”. A study cannot conclude something but you can say things like “these authors concluded”. In addition, when you talk about research that has been done in the past or published materials you need to talk about them in the past tense.
Conclusion
In your conclusion write a paragraph about what your overall thoughts about the article were and if you found the article to be useful as well as why or why not. Also include if you think this article would be helpful to another researcher and why/why not.
References
Include any references you used in your paper other than the article you critiqued in APA format.