Assignment #4

Experimental Methods in Psychology - Psychology 3650

Spring 2004 – University of North Texas

 

 

General Requirements 

You will be asked to create a decision aid for determining the type of research used in studies.  You will then use this aid to provide details about research reported in research briefs.  You will also be asked to identify potential threats to construct validity, internal validity, or external validity in a set of research briefs.  Submit your responses using the guidelines of Assignment 3 to help content and formatting issues.  You will submit a typewritten, double-spaced, and stapled (if necessary) paper. Be sure to include a copy of your decision aid with your responses.

Constructing a Decision Aid

The decision aid should resemble a decision tree or flow chart that will allow you to determine the type of research from a set of simple queries.  The general steps of identifying research are given below.  Your task is to take those general steps and formalize them into a decision aid that will identify all of the research designs discussed in class: descriptive, correlation, multiple regression, two groups, single factor multigroup, factorial, attribute-by-treatment interaction, quasi designs, within-subjects factor designs (including mixed factors), and multivariate designs.  Rough examples of a decision aid will be given in class.  In designing your decision aid, you should think about the importance of each general step listed below.

 

General steps to identify research designs

  1. Is the IV continuous or categorical?
  2. How many IV’s?

-         How many levels of each?

  1. How many DV’s?
  2. Are there special manipulations of the IV?

-         Quasi factor?

-         Within-subjects factor?

-   Repeated measure?

  1. What statistics are associated with each type of design/element?

 

Report of Research Briefs  

For each research brief given on the next pages, use your decision aid to identify the type of design.  You should then give details about potential flaws in the research procedures and give solutions for the flaws.

 

More specifically, for each experiment brief, you should:

  1. Identify the IV(s)…operationally defined.
  2. Identify the DV(s)… operationally defined.
  3. Clearly (and specifically) state the type of design.
  4. Name the type of statistical test you would use to analyze the data.
  5. Write a clear and testable hypothesis.
  6. Identify a major experimental defect.
  7. State whether this defect is a threat to construct validity, internal validity, or external validity.
  8. Give a solution to the defect.