The research process Psych 231 Research Methods in

The research process Psych 231: Research Methods in Psychology

n This is the final lecture n n Wednesday (optional) – Review Q&A, help with posters, etc. Labs this week n n n Poster presentations Turn in group ratings sheets Turn in results and reference section for group project Announcements

n Cross-sectional design n Study groups of individuals of different ages at the same time • Age is subject variable treated as a between-subjects variable n Age 4 Age 7 Age 11 Longitudinal design n Follow the same individual or group over time • Age is treated as a within-subjects variable time Age 11 Age 15 Age 20 Developmental designs

n Cohort-sequential design n Measure groups of participants as they age • Example: measure a group of 5 year olds, then the same group 10 years later, as well as another group of 5 year olds n Age is both between and within subjects variable • Combines elements of cross-sectional and longitudinal designs • Addresses some of the concerns raised by other designs • For example, allows to evaluate the contribution of cohort effects Developmental designs

n Cohort-sequential design Cross-sectional component Time of measurement 1975 Cohort A 1970 s Cohort B 1980 s Cohort C 1990 s Age 5 1985 1995 Age 15 Age 25 Age 15 Age 5 Longitudinal component Developmental designs

n Cohort-sequential design n Advantages: • Get more information • Can track developmental changes to individuals • Can compare different ages at a single time • Can measure generation effect • Less time-consuming than longitudinal (sort of) • Can examine age comparisons along the way n Disadvantages: • Still time-consuming • Need lots of groups of participants • Still cannot make causal claims (about the age variable) Developmental designs

Presenting your work Get an idea § § § A set of skills leading to knowledge & understanding A way of thinking (beware small samples, correlation is not causation, etc. ) A way of life? Stats. org: Stats in the news Course Review: The Research Process

§ Get an idea – – Often the hardest part No firm rules for how to do this – – Observations Past research – Review the literature The Research Process

n Review the literature n What has already been done? • What variables have people looked at • What hasn’t been looked at n n How are other experiments in the area done? What methods are used? • To measure the dependent variable • To manipulate the independent variable • To control extraneous variables The Research Process

§ Formulate a testable hypothesis – What is a hypothesis? – – A predicted relationship between variables What does it mean to be testable? – – – Must be falsifiable Can it be replicated Must be able to observe/measure (and manipulate for experiments) the variables – – – Directly Indirectly Operational definitions The Research Process

n Design the research – – What method? – What kind of comparisons are used – – – Control groups Baseline conditions What are your variables? – – – Experiment, Survey, Developmental designs, … How many levels of your Independent variable(s) How do you measure your dependent variable(s) What can be done to control for biases and confounds? The Research Process

n Collect Data n n Importance of pilot research Who do you test? • What is your population? • Your sample? • Your sampling method? The Research Process

n Analyze the data n n Design drives the statistics Understanding Variables and variability • Descriptive statistics (summarizing) • Means, standard deviations • Graphs, tables • Correlation • Inferential statistics (drawing conclusions) • • What kind of analysis is appropriate for your design T-tests ANOVA Between or within versions The Research Process

n Interpret the results n n n Correlation versus causation Reject or fail to reject null hypotheses Statistical vs. theoretical significance Support or refute theory (or revise) Generalizability of the results The Research Process

n Present the results n Getting the research “out there” • Conference presentations • Posters • Talks • Written reports • APA style • Supports clarity The Research Process

n Repeat n Each set of results leads to more research questions • Refine theory • Test a refined theory • Test alternative explanations The Research Process

n Wed Dec. 14 1: 00 -2: 50 n It is cumulative, covers the entire course. The majority is on new material (roughly 65%), the rest is material covered on Exams 1 & 2. All multiple choice/scantron for the final n Reviewing for the final exam

n n Final 1/3 of the course Non experimental methods n Survey, correlational, & developmental Statistics n Descriptive n Inferential Presentations n Papers, Posters, & Talks Reviewing for the final exam

n First 2/3 of the course § Scientific method n § § § § n Getting ideas Developing (good) theories Reviewing the literature Psychological Science Ethics Basic methodologies APA style § Underlying reasons for the organization § Parts of a manuscript n n Variables Sampling Control Experimental Designs n n Vocabulary Single factor designs Between & Within Factorial designs Reviewing for the final exam