Causal Research: Experimentation

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Causal Research Experimentation
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Conditions for Inferring Causality

• Temporal Ordering
• Evidence of Association
• Controlling other extraneous variables

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Experimental Setting

• Field External Validity
• Lab Internal Validity

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Threats to Internal Validity

• History Effect
• Maturation Effect
• Testing Effect

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Threats to External Validity

• Reactive Bias
• Sterile Environment

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BAKHILL FOODS
Research Objective(s)

• Independent variable(s)
• Dependent variable(s)

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Decisions Regarding the Independent Variables (X)

• Number of levels of each factor (independent
  variable)
• Within or between subject factors

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Decisions Regarding the Dependent Variables (O)

• Operationalize the Construct
• Develop the Measure(s)

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Experimental Issues

• What Experimental Design did Bakhill Foods use?
• How did they control for internal validity?
• What threats to internal validity persist?
• How did they control for external validity?
• What threats to external validity persist?

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Bakhill FoodsExperimental Design
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Bakhill FoodsExperimental Design
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Experimental Issues

• How did they control for internal validity?
• What threats to internal validity persist?
• How did they control for external validity?
• What threats to external validity persist?

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Bakhill FoodsAnalysis
Entering data ID 13 DV items Model Attract
(0,1) Model gender (0,1) Subject gender (0,1)
Effects
Main Effects
Model Attractiveness (MA) Model Gender
(MG) Subject Gender (SG)
Interactions
MA x MG MA x SG MG x SG MA x MG x SG
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Main Effects
Male model
Cognition Score
Female model
Unattractive Attractive Model
Model
All Subjects
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2-Way Interaction
Male ( female) Model
Female Subjects
Conative Score
Male Subjects
Unattractive Attractive Model
Model
16
3-Way Interaction
Female Subjects
Male Subjects
Female model
Male model
Male model
Female model
Unattractive Attractive Model
Model
Unattractive Attractive Model
Model