1. Research Methods in Developmental Psychology Michael Hoerger

2. Observation Hypothesis generation Laboratory Observation: Parent-child interactions, marriages, intrusive interviews, attachment style Naturalistic observation: bullying, ADHD Used to gain detailed information on a single or small number of cases, commonly used in medicine and clinical psychology: rare events, new events, complex events Case Study

3. Correlation

4. r = Strength of relationship between two variables (-1 to +1) What is a big correlation? Reliability: r =.90 IQ tests: r =.50 to.90 Personality research: r =.30 Life/death: r =.01 Problem: Correlation Causation due to 3 rd variable problem and directionality problem Solution: Methods and argument

5. Cross Lagged Panel Design (or Cross lag panel or Cross panel lag) Look at correlation between two variables over time Does X correlated with changes in Y? Smoking at Time 1 causes increased mile time at Time 2

6. Look at correlation between two variables over time Does X correlated with changes in Y? Maternal depression at Time 1 causes increased behavior problems at Time 2

8. THIS DRUG HAS HELPED TO TREAT: HAY FEVER, ASTHMA ATTACKS, ANXIETY, PAIN, ULCERS, ENURESIS, WARTS, ARTHRITIS, MALIGNANT TUMORS, DIABETES, NARCOTIC WITHDRAWAL, INSOMNIA, COLDS, AND INATTENTIVENESS

9. Experiment id! Independent variable: the manipulation; different conditions or groups Alcohol vs. placebo; CBT vs. waitlist Dependent variables: depends on the independent variable; the outcome variable Age at death; depression; liver functioning Problem: Participants must be similar across IV groups Solution: Random assignment

10. Survey Interviews, questionnaires, tests Used for correlational studies or as outcome (DV) measures in experimental studies Highly efficient Can be anonymous Problems: Wording, Response bias (e.g. social desirability) Solutions: Design with care

11. Online Research Most surveys and some experiments can be run on the web (e.g. priming studies) Benefits: most efficient, useful for screening large samples Risks: Lower experimental control, random responding, technical problems, non- representative sampling, ethics http://funpsych.com example http://funpsych.com

12. Physical Measures Physiological: changes in functioning Galvanic skin response (sweating), pupil dilation, heart rate Physical: walking speed, eye movement, speed of responding, height, weight Neurological: neurotransmitter levels, brain structure Benefits: reliability of measurement Risks: expensive, often fail to provide new information, low correspondence

13. Cross-Sectional Research Groups differ by age Compare children to teens to young adults to older adults Differences are presumed to be the result of age Older people are slower due to aging BUT differences may simply be due to contextual factors, such as the era each group was born in OR older people are slower due to differences in nutrition growing up

14. Longitudinal Research Follow one group over time to what changes with age Problem: expensive, bias due to dropout Combines cross-sectional and longitudinal research Cross-Sequential Research

15. Michael Hoerger To cite this lecture: Hoerger, M. (2007, January 10). Research Methods in Developmental Psychology. Presented at a PSY 220 lecture at Central Michigan University.