1. Experimental Design
Research Methods

2. Independent variable (treatment)
The independent variable is manipulated by the experimenter.
Examples of independent variables include: Fitness levels, type of practice, contextual interference, strategy for imagery, music …
Controls
Active and assigned variables
Between subjects and within subjects (repeated measure) variables

3. Within Subjects/Repeated Measure
Counterbalancing, using a Latin Square Design
When an experiment has multiple treatments, conditions, or tasks they can be counterbalanced across subjects by using a Latin Square Design. In using a Latin Square Design all orders are not represented; however , all conditions are represented at least once in each position of the order to observe the effects of position and to control for practice, boredom, fatigue….
Order 1 A B C
Order 2
Order 3

4. Standardization Validity Reliability Objectivity Sensitivity
Dependent Variable
The dependent variable is the variable measured by the experimenter (e.g., reaction time, heart rate, VO2Max, a survey score)
Concerns
Standardization
Validity
Reliability
Objectivity
Sensitivity

5. Statistical Testing Differences Associations Relationships
Categorical Independent Variables; Continuous Dependent Variables
Differences
T-test
ANOVA
Categorical Independent Variables; Categorical Dependent Variables
Associations
Chi squared
Continuous Independent Variables; Continuous Dependent Variables
Relationships
Correlation
Regression

6. Null Directional Alternative
Writing Hypotheses
Null Directional Alternative

7. Null Hypotheses
State the null hypothesis when no literature exists State the null hypothesis when the literature is controversial or equivocal State when there is no theoretical direction

8. Writing Null Hypotheses
Stated in the null form
Independent variable (insert name) will not affect dependent variable (insert name).
Independent variable (insert name) will not associate with the dependent variable (insert name).
Independent variable (insert name) will not relate to the dependent variable (insert name).

9. Directional Hypothesis
State when the literature provides a clear direction State when the literature is unequivocal State when good theoretical support exists

10. Writing Directional Hypotheses
Independent variable (levels A and B) will affect the dependent variable such that A will be significantly different than B. Independent variable (levels A and B) will associate with the dependent variable such that B will be significantly associated with B in specific ways. Independent variable (levels A and B) will relate to the dependent variable such that B will be significantly and positively (or negatively) related to B.

11. Writing Problems
How does the independent variable affect the dependent variable? How does the independent variable associate with the dependent variable? How does the independent variable relate to the dependent variable?

12. Main Effects and Interaction effects
Also you might need to consider interaction and main effects? What if you have two independent variables? Main effects include the analysis of a single independent variable and all of its levels. Interaction effects include the analysis of more than one independent variables and the interaction of all of their levels.

13. Interaction of Two Independent Variables (3*2 factorial design)
Gender
Male
Female
Overall Mean
Type of Practice
Massed
Distributed
Control

14. Pure Experimental Designs
Randomized groups Design Pretest-Posttest Randomized-Groups Design Solomon Four-Group Design

15. Randomized-Groups DesignT O1 O2

16. Pretest-Posttest Randomized-Groups Design

17. Solomon Four-Group DesignT O2 O3 O4 O5 O6