Methods of Developmental Psychology

1. Methods of Developmental Psychology • Introduction • The scientific method • Research methods • Dimensions of research method • The normative-explanatory dimension • The naturalistic-manipulative dimension • Naturalistic observations • Controlled/experimental observations • The atheoretical-theoretical dimension • The ahistorical-historical dimension • Designs of developmental research • Longitudinal designs • Cross-sectional designs • Sequential designs • Comparative designs • Cross-cultural designs • General methodological problems • Contamination • Researcher effects • Reconstruction through retrospection • Faulty logic • Inadequate definition of concepts • Sampling • Overgeneralization

2. Dimensions of Developmental Research • The normative-explanatory dimension • Normative research describes some typical behavior • Explanatory research provides explanations for developmental differences • The naturalistic-manipulative dimensions • Naturalistic research observes behavior in its natural setting • Controlled or experimental observations put the child in situations that will maximize the occurrence of the behavior of interest • The atheoretical-theoretical dimensions • Involves the relative emphasis on theory as a basis of research • The ahistorical-historical dimensions • Ahistorical research studies behavior at one particular point in time • Historical research is concerned with the origins and future courses of behavior

3. The Longitudinal Design Age at time of testing 6 years 8 years 10 years Involves assessing the same group of people over an extended period of time • Advantages of the approach • Similarities or differences in behavior across development are seen directly • Identifies real age changes, not just differences between age groups • Drawbacks of the approach • Expensive and time consuming • Nature of the people studied • Increasing bias as the study continues • Problems with changes in measurement

4. The Cross-Sectional Design Age group for testing 6 year-olds, 8 year-olds, & 10 year-olds Involves assessing differently aged groups of people at the same time of testing • Advantages of the approach • Less time-consuming, and less expensive than longitudinal designs • Efficiently derived description of development • Drawbacks of the approach • Difficult to control for all variables that might differ between different groups of subjects • Differences between groups might be a reflection of differences in age cohorts • Thus, only estimates developmental change, does not measure it directly

5. The Sequential Design • Cohort age Information Information • (in 1995) gained CS1 gained CS2 •  • 6-year-olds Immediate L1Enduring impact • impact onon children who • 6-year-oldsare now 8 yrs old •  •  • 8-year-olds Immediate L2Enduring impact • impact onon children who • 8-year-oldsare now 10 yrs old •  •  • 10-year-olds Immediate L3Enduring impact • impact onon children who • 10-year-oldsare now 12 yrs old •  •  • 1st cross-sectional 2nd cross-sectional • comparison tells us comparison tells us • at which age training (1) which cohort • program has largest benefited most in immediate impact the long run; (2) helps to decide which future program might • be implemented to • maximize long- term impact

6. The Comparative and Cross-Cultural Research Designs • Comparative research • Attempt to learn something about human development through comparison to non-human development • Permits controlled tests of hypotheses that would be unethical to test with humans • Cross-cultural research • Compares subjects from different cultural backgrounds • Allows investigator to determine whether conclusions drawn about children in one social or cultural context generalize to children in other contexts • Cross-cultural differences versus cross-cultural similarities

7. General Problems with Research and Developmental Research • Contamination • Data is influenced by factors other than those being studied • Researcher effects • The researcher unintentionally influences the results of the study • Demand characteristics • Reconstruction through retrospection • Biases introduced through inaccurate memories • Faulty logic • Problematic reasoning in interpreting data • Inadequate definition of concepts • Problems in how abstract concepts are defined and operationalized • Sampling • Errors introduced through the type of subject recruited for the study • Overgeneralization • The application of findings to situations that are not appropriate or similar enough