Slide 1Slide 2Scientific MethodDevelopmental Research (overview)Naturalistic observationSurveys/QuestionnairesInterviewsCase StudiesStandardized TestsPhysiological TestingCorrelational ResearchSlide 12Slide 13Slide 14Correlation =/= CausationThird variable problemExperimental MethodExperimental MethodExperimental MethodDevelopmental Methods (Overview)Cross-sectional DesignLongitudinal DesignCross sectional and LongitudinalSequential/Time Lag DesignConducting Ethical ResearchResearch MethodsScientific Study of Human DevelopmentGoals1. Understand how and why people change2. Understand how and why people stay the sameScientific Method1. Focus on a topic 2. Formulate a hypothesis3. Test the hypothesis via research designs4. Collect and analyze data (data collection methods vary)5. Draw conclusions6. Make results availableDevelopmental Research(overview)•Descriptive Research•Naturalistic Observation•Surveys/questionnaires•Interviews•Case Studies•Standardized tests•Physiological measures•Correlational Research•Experimental ResearchNaturalistic observation•Directly observe people in their natural environments•Try not to disrupt the flow of their behavior •Used to discover patterns in behavior but can’t infer cause•Pros & cons?•Pro•See humans in natural environment•Con•Time consumingSurveys/Questionnaires•Pros & Cons?•Pro•A lot of data in little time•Con•Social desirabilityInterviews•Structured Interview•Questions never vary•Semi-structured Interview•Questions may change depending on answersCase Studies•In depth examination of one individualStandardized Tests•Uniform procedurePhysiological Testing•Measures biological/chemical functioningCorrelational Research•Describes strength and direction of relationship between 2 variables•Correlation Coefficient (r)•Ranges from -1 and +1•Positive•Negative•0 = no relationshipCorrelation does not mean causationActs ofaggressionLessExposure to violent TVLessPOSITIVE CORRELATIONMoreMoreIllnessesLessMoreOptimism scoresLowNEGATIVE CORRELATIONHighCrimesLessMorePhases of the moonNewZERO CORRELATIONFullCorrelation =/= Causation•As ice cream sales increase, the rate of drowning deaths increases sharply.•Therefore, ice cream causes drowning.•Sleeping with one's shoes on is strongly correlated with waking up with a headache.•Therefore, sleeping with one's shoes on causes headache.Third variable problem•May Mean:•X causes Y (scenario 1)•Y causes X (scenario 2)•Z causes X and Y (scenario 3)Experimental MethodVariables•Behavior and events that we try to define•Something that changesIndependent Variable versus the Dependent Variable•Independent Variable is what is controlled, manipulated and assumed to have an impact.•Predictor•Dependent Variable is the factor that is measure in an experiment. It may change due to the manipulation of the independent variable.•OutcomeExperimental Method•Groups•Experimental Group•Control Group•Randomization•Random Selection•Random Assignment•Groups are the same before treatment•Only thing that changes is the treatmentExperimental MethodDevelopmental Methods (Overview)1. Cross-Sectional2. Longitudinal (Prospective)3. SequentialCross-sectional Design•Assess Individuals of different ages all at the same time•Advantage: Practical•Disadvantage: •Cohort Effect: differences between age groups is due to generation issues, not age differencesLongitudinal Design•Assess the same individuals at different times•Advantages: •Reveals continuity and change with age•No cohort effect•Problems: •Hard to do ($)•Attrition•Test familiarity•Time of testing effect: cant separate age effects from time effect8 years old18 years old 28 years oldCross sectional and Longitudinal•Cross sectional•Pros•Time efficient•Less expensive•No time of testing effect•Cons•Cohort Effect•Longitudinal•Pros•No Cohort Effect•See individual change•Cons•Time of Testing Effect•Attrition•Expensive•Long timeSequential/Time Lag Design•Test different cohorts at different years•Combine cross-sectional and longitudinal designsConducting Ethical Research•Rights of participant •Responsibilities of researchers •APA’s guidelines address several important issues 1. Informed Consent2. Confidentiality3. Debriefing4.