Introduction to ANOVA

The Analysis of Variance (ANOVA) method is the most popular and highly used statistical technique by researchers. Like T tests, ANOVAs are used to compare the means of groups for a given independent variable to determine whether they are statistically different from each other. However, T tests can only compare two groups. ANOVAs allow you to compare two or more (usually, ANOVAs are conducted with at least three groups). Using ANOVA, you can compare all mean differences simultaneously. This is advantageous as using multiple t tests increases the rate of Type I error, which means rejecting the null hypothesis when it is true (Tarlow, 2016).

For example, say you are interested in whether socioeconomic status is related to individuals self-reported happiness. By separating the individuals into groups representing low, middle, and high socioeconomic status (or even low, low-mid, mid, mid-high and high, or some other combination of groups), you could then determine whether mean reported happiness is different across each of the groups. How many groups might you need to investigate in your own research? If the answer is more than two, then this will be an important week. This week, you will extend your knowledge by identifying and applying the use of a one-way ANOVA test.

References/ Materials

Tarlow, K. R. (2016). Teaching principles of inference with ANOVA. Teaching Statistics, 38(1), 1621.

  • American Psychological Association. (2020). Academic Writer. American Psychological Association.
  • Knapp, H. (Academic). (2016). ANOVA [Streaming video]. SAGE Research Methods.

Statistical reasoning for everyday life

Bennett, J. O., Briggs, W. L., & Triola, M. F. (2017). Statistical reasoning for
everyday life (5th ed.). Boston, MA: Pearson-Addison Wesley.

This is the required Redshelf textbook for the course. You will be using this textbook all through the course for weekly assignments. For this week, review Chapters 9 and 10. Access the textbook in the Getting started module of your course or the Bookshelf link at the top of your course. 

Instructions

Download the assignment template and data files from this weeks resources and review the steps for this assignment. Once you have reviewed the steps, complete the problems and questions as presented. Show your work using your statistical program output. You may show manual/hand calculations only if the SPSS program cannot be accessed. There are two deliverables you must submit this week:

  • SPSS output file or manual calculations: Submit the SPSS output file in PDF form, or you can scan your work and submit it as a low-resolution graphic.
  • Word document: Submit a Word file answering the questions asked in the assignment. Describe the results in APA style incorporating relevant tables and figures formatted in APA style. 

Length: SPSS output or manual calculations and 1 to 2-page Word document

The completed assignment should address all of the assignment requirements, exhibit evidence of concept knowledge, and demonstrate thoughtful consideration of the content presented in the course. The writing should integrate scholarly resources, reflect academic expectations and current APA standards, and adhere to Northcentral University’s Academic Integrity Policy.