Developing Hypotheses

1
Developing Hypotheses

• Chapter 3
• Psychology 301

2
Developing Ideas

• Wallass 4 stages
• Preparation
• Incubation
• Illumination
• Verification

3
Creating Hypotheses

• Using reasoning
• Inductive reasoning
• Generalizing from a few specific observations or
  experiences to a general law
• Deductive reasoning
• Reasoning that proceeds from general principles
  or premises to derive particular information.

• Strong Induction
• All observed crows are black.
• Therefore
• All crows are black.

• Weak Induction
• I always hang pictures on nails.
• Therefore
• All pictures hang from nails.

• Deduction
• We learn to behave by watching others.
• Therefore
• Children who watch violent television will be
  more aggressive.

4
Making Hypotheses Concrete
The Nomological Net
Marital Satisfaction
Depression
Self-report
Therapist Evaluation
Dyadic Adjustment Scale
Sexual Frequency
5
Making Hypotheses Testable

• Need to operationalize variables in a way to
  measure them reliably and validly
• Reliability
• Test-retest
• Interrater
• Internal consistency
• Validity
• Concurrent
• Discriminant

6
Making Strong Inferences

• Platt (1964)
• Strong inference characterized by
• Devising alternative hypotheses
• (making competing predictions based different
  theories)
• Devise study(ies) where the occurrence of one
  outcome would exclude the other
• Conduct the study(ies)
• Go back to step 1 and refine theory of supported
  hypothesis
• Example Is separation due to military deployment
  harmful to marriages?
• Absence makes the heart grow fonder
• Prediction deployment will not be harmful
• Out of sight out of mind
• Prediction deployment will be harmful