1. Psy 311: Methods1 GOALS OF DEVELOPMENTAL PSYCHOLOGY l Describe, explain, and optimize human development

2. Psy 311: Methods2 GOALS OF DEVELOPMENTAL PSYCHOLOGY l 1. DESCRIBE –characterize the behavior of human beings of different ages and trace how it changes with age –normal development & individual differences

3. Psy 311: Methods3 GOALS OF DEVELOPMENTAL PSYCHOLOGY l 2. EXPLAIN –understanding why humans develop as they do –why people develop similarly & differently.

4. Psy 311: Methods4 GOALS OF DEVELOPMENTAL PSYCHOLOGY l 3. OPTIMIZE –how people can be helped to develop in a positive direction –prevention & remediation

5. Psy 311: Methods5 METHODS OVERVIEW l WHO: Sampling l WHAT: Measures l HOW: METHODS l WHEN: DESIGN

6. Psy 311: Methods6 CHALLENGE TO LIFE-SPAN DEVELOPMENT l METHODS –How can we demonstrate causality? –How can we study different pathways of development? –How can we study changing people in a changing world?

7. Psy 311: Methods7 METHODS l TYPES OF METHODS –Correlational –Experimental

8. Psy 311: Methods8 CORRELATIONAL METHOD l WHAT IS IT? –Looks at naturally existing relationships. –Studies people who have already had experiences. –Assigned “naturally” to groups.

9. Psy 311: Methods9 CORRELATIONAL METHOD (cont.) l DISADVANTAGES –Can’t prove cause-effect relations between variables. Could be the reverse effect. Could be something else that causes both variables.

10. A Teacher Involvement B Child’s Motivation C Child’s Gender

11. Psy 311: Methods11 EXPERIMENTAL METHOD l WHAT IS IT? –1. Random assignment of people to “treatment” and “control” groups. –2. Manipulate the independent or “causal” variable. –3. Comparison groups are identical on everything but the treatment.

13. Psy 311: Methods13 EXPERIMENTAL METHOD (cont.) l ADVANTAGES –Can establish cause-effect relations between variables. Does show cause and effect. –Does not rule out reverse relationship.

14. Psy 311: Methods14 EXPERIMENTAL METHOD (cont.) l DISADVANTAGES –“Treatment” may be artificial. –May not work this way in the real world. – “Can” cause vs. “does” cause. –Lots of interesting causal variables cannot be manipulated.

15. Psy 311: Methods15 CORRELATIONAL METHOD (cont.) l ADVANTAGES –Can be applied to data collected in natural settings. –Can be more applicable to the real world. –Can be used to study issues that cannot be studied experimentally.

16. Psy 311: Methods16 EXPANDING METHODS (cont.) l CORRELATIONAL –Examining beginnings. –Adding time sequences. l EXPERIMENTAL –Natural experiments. –Optimizing interventions.

17. Psy 311: Methods17 DEVELOPMENTAL DESIGNS l TYPES OF DESIGNS –Cross-Sectional –Longitudinal –Sequential

18. Psy 311: Methods18 CROSS-SECTIONAL DESIGN l WHAT IS IT? –At one time point. –Look at people of different ages.

19. Psy 311: Methods19 CROSS-SECTIONAL DESIGN (cont.) l WHAT DO YOU GET? –Information about age differences.

20. Psy 311: Methods20 CROSS-SECTIONAL DESIGN (cont.) l DISADVANTAGES –1. Age differences may be COHORT differences. BIRTH COHORTS: People of the same generation or born at about the same time.

21. Psy 311: Methods21 CROSS-SECTIONAL DESIGN (CONT) l DISADVANTAGES –2. Provides no information about... –how a person changes over time. –how earlier experiences influence later development.

22. Psy 311: Methods22 LONGITUDINAL DESIGN l WHAT IS IT? –At many points in time; repeatedly –Follow the same group of people

23. Psy 311: Methods23 LONGITUDINAL DESIGN (CONT) l WHAT DO YOU GET? –Information about age changes

24. Psy 311: Methods24 LONGITUDINAL DESIGN (cont.) l ADVANTAGES –1. Actually can study how a person changes over time. –2. Actually can study how different people change over time. –3. Actually can study… how earlier developments are linked to later development. how earlier experiences influence later development.

25. Psy 311: Methods25 LONGITUDINAL DESIGN (cont.) l DISADVANTAGES –1. Age changes may be HISTORICAL changes.

26. Psy 311: Methods26 LONGITUDINAL DESIGN (cont.) l DISADVANTAGES –2. Participants may be affected by participation in study. e.g., repeated testing –3. Participants may drop out.

27. Psy 311: Methods27 LONGITUDINAL DESIGN (cont.) l DISADVANTAGES –4. Measures may later prove inadequate. –5. Practical problems time consuming expensive

28. Psy 311: Methods28 CROSS-SECTIONAL DESIGN (cont.) l ADVANTAGES –1. Does give information about age differences. –2. Hints at developmental trends. –3. Practical. takes little time to conduct inexpensive.

29. Psy 311: Methods29 SEQUENTIAL DESIGN l WHAT IS IT? –Combines cross-sectional and longitudinal designs. –Longitudinal studies on multiple generations or cohorts.

30. Psy 311: Methods30 SEQUENTIAL DESIGN (cont.) l WHAT DO YOU GET? –1. Age differences and Cohort differences. –2. Age changes and Historical changes.

31. Psy 311: Methods31 SEQUENTIAL DESIGN (Cont) l ADVANTAGES –1. Compares development at different historical periods –2. Compares development of different cohorts

32. Psy 311: Methods32 SEQUENTIAL DESIGN (Cont) l DISADVANTAGES –1. Complex –2. Time consuming –3. Still only generalizable to the cohorts and historical periods you DID measure –4. You may find effects you do not want.

33. Psy 311: Methods33 DESIGNS FOR DEVELOPMENTAL QUESTIONS

34. Psy 311: Methods34 CROSS-SECTIONAL l Advantages –Age differences –Suggests change –Inexpensive, quick l Disadvantages –Age differences could be cohort differences –No information about change or effects of early experience

35. Psy 311: Methods35 LONGITUDINAL l Advantages –Age change –How people develop differently –Connections between early & later development l Disadvantages –Age change could be historical change –Expensive & long –Drop out –Repeated testing

36. Psy 311: Methods36 SEQUENTIAL l Advantages –Age changes –Historical changes in development l Disadvantages –Really complex, expensive & long

37. Psy 311: Methods37 WHAT IS THE BEST DEVELOPMENTAL DESIGN? l Age differences –CROSS-SECTIONAL exploratory l Age changes –LONGITUDINAL effects of earlier experiences l Historical changes –SEQUENTIAL

38. Psy 311: Methods38 WHAT IS THE BEST DEVELOPMENTAL DESIGN (CONT)? l Truly Developmental –LONGITUDINAL l Most Complete –SEQUENTIAL l Depends on the question

39. Psy 311: Methods39 LAST NAME, first name l 1. Name the major problem with each design: a) Correlational b) Experimental c) Cross-sectional d) Longitudinal e) Sequential

40. Psy 311: Methods40 END