Research Methods
Summer 2009
Using Between Subjects and Within Subjects
Experimental Designs
7/20/03 Copyright Ed Lipinski and Mesa Community College, 2003-
2009. All rights reserved.
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General Housekeeping
Assignments
Lesson Objective
Ed’s Overview / Discussion
Questions.
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“... to examine the use of between subjects and within subjects experimental designs”
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• I. Types of Experimental Designs
• II. Error Variance
• III. Between Subjects Designs
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IV. Within Subjects Designs
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I.V.’s and D.V.’s
• VI. Confounding.
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Cohorts – APA Style…
• Why do you believe the APA has created writing guidelines for professional publications?
• What was the most helpful element associated with using APA Style? Why?
• What was the most difficult challenge associated with using APA Style? Why?
• What might I do differently next time I write an
APA Style Paper?
• What might be some ethical considerations associated with the report I wrote or the writing style that I used?.
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Cohorts – Top Five…
• Cohort ‘A’: Making Systematic
Observations
• Cohort ‘B’: Using Survey Research
• Cohort ‘C’: Using Between-Subjects and Within-Subjects Designs.
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Class Discussion
• What is a Between-Subjects Design?
• Between-Subjects: Different groups of subjects are assigned to the levels of your independent variable
• Pros and Cons of this Design.
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Class Discussion
• What is a Within-Subjects Design?
• Within-Subjects: A single group of subjects is exposed to all levels of your independent variable
• Pros and Cons of this Design.
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Class Discussion
• What is a Single-Subject Design?
• Single-Subject Design: The subject is exposed to all levels of the independent variable, however, you do not average statistically across subjects
• Pros and Cons of this Design.
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• A. Looking For Cause
• B. Quantitative and Qualitative
Manipulation
• C. Between Subjects Designs
• D. Within Subjects Designs
• E. Single Subject Designs.
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• A. Error Variance
• B. Sources of Error Variance
• C. Handling Error Variance
• Reducing Error Variance
• Increasing Effectiveness of I.V.
• Randomizing
• Statistical Analysis.
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• A. Single Factor Randomized Groups
Design
• Randomized Two-Group Design
• Randomized Multigroup Design
• Parametric Design
• Nonparametric Design
• Multiple Control Group Design.
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• B. Matched Groups Design
• Matched Sets Distributed At Random
• Logic
• Advantages and Disadvantages
• Matched Pairs Design
• Matched Multigroup Designs.
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• A. Advantages
• B. Disadvantages
• C. Sources of Carryover
• Learning
• Fatigue
• Habituation
• Sensation
• Contrast
• Adaptation.
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• D. Dealing With Carryover
• Counterbalancing
• Complete Counterbalancing
• Partial Counterbalancing
• Latin Square Design
• Minimizing Carryover
• Treatment Order As An I.V..
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• E. When To Use
• Subjects Correlated With D.V.
• Economizing On Subjects
• Increasing Exposure
• F. Versus Matched Groups
• G. Types of Within-Subjects Designs
• Single Factor Two-Level Designs
• Single Factor Multilevel Designs.
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• A. Factorial Designs
• Separate Group For Each I.V. Level
• Main Effects
• Interactions
• Factorial Within Subjects Designs
• Higher Order Factorial Designs
• B. Other Group-Based Designs
• C. Multivariate Designs – More D.V.’s.
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• A. Varying With The I.V..
• Maturation
• History.
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I.
Types of Experimental Designs
II. Error Variance
III. Between Subjects Designs
IV. Within Subjects Designs
V.
I.V.’s and D.V.’s
VI. Confounding.
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Questions
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