AP Psychology Chapter 2 Research Methods

AP Psychology Simple Studies Review Chapter 2: Research Methods Terminology ● Hypothesis: expresses a relationship between two variables ● Variables o The independent variable is intentionally changed o The dependent variable depends on the independent variable (what is being studied) ● Theory: aims to explain some phenomenon, allows researchers to generate testable hypotheses with the hope of collecting data that support the theory ● Operational Definitions: explanations of how variables will be measured ● Validity and Reliability o Validity: accurately measures what the researcher set out to measure o Reliability: it can be replicated and is consistent ▪ Split-half reliability: dividing the test in 2 should yield 2 equal scores ▪ Test-retest reliability: same test, 2 occasions, same score ● Participants (Subjects): the individuals on which the research will be conducted ● Sampling: the process by which participants are selected ● Sample: the group of participants selected to be in the study ● Population: anyone or anything that could possibly be selected in the sample ● Random Selection: every member of the population has an equal chance of being selected o Increases the likelihood of a representative sample, but does not guarantee it o Allows researchers to generalize about their results ● Stratified Sampling: allows a researcher to ensure that the sample represents the population on some criteria (ex. race) o Sample size uses proportions equal to that of the population ● Hindsight Bias: Upon hearing research findings, the tendency to believe that you knew it all along ● Applied Research: Has clear, practical applications 1 o Basic Research: explores questions that are of interest to psychologists, not intended to have immediate real world applications Experimental Method ● Experiment: the only way to show a cause-effect relationship/preferred research method o Laboratory Experiments: experiments in a lab allow lots of control o Field Experiments: experiments out in the real world, more realistic but less control ● Confounding Variables: any difference between the experimental and control conditions that could affect the dependent variable (other than the independent variable) ● Assignment: the process by which participants are put into the experimental or control group o Random Assignment: each participant has an equal chance of being placed into any group, limiting the effect of participant-relevant confounding principles ● Experimenter Bias: the unconscious tendency for research members to treat members of the experimental and control groups differently to increase the chance of confirming the hypothesis ● Double-Blind Procedure: neither the participants nor the researcher are able to affect the outcome of the research o Eliminates both experimenter and subject bias ● Single-Blind Procedure: only the subjects don’t know to which group they’ve been assigned o Minimizes demand characteristics and participant bias ▪ Demand characteristics: cues about the purpose of a study that affect the participants’ responses o Response/participant bias ▪ the tendency for subjects to behave in certain ways ▪ Leading question (framing): specific wording that leads to bias ▪ Social desirability bias: the tendency to try to give politically correct answers 2 ● Experimental Group: gets the treatment operationalized in the independent variable ● Control Group: does not get the independent variable o Without it, knowing the effects of the experimental treatment is impossible o Establishes a baseline ● Hawthorne Effect: selecting a group of people on whom to experiment affects the performance of that group, regardless of what is done to them ● Placebo Effect: subjects’ own beliefs of cause can manifest themselves even in the absence of treatment ● Counterbalancing: using participants as their own control group o To eliminate order effects, have half do one order, the other half the other, then switch Correlational Method ● Correlations: express a relationship between two variables o Positive: the presence/increase of one predicts the presence/increase of the other o Negative: the presence/increase of one predicts the absence/decrease of the other o Does not imply causation! ● Problems o Cause and effect cannot be determined o The assignment of the independent variable is predetermined o Controls all other aspects of the research process ● Correlation Coefficient: Ranges from -1 to +1 and describes the strength/direction of a relationship o -1 = perfect negative correlation o +1 = perfect positive correlation o 0 = weakest possible correlation ● Survey Method: asking people to fill out surveys o Investigates relationships, but not causation o No independent or dependent variables o Participant-relevant confounding variables can’t be controlled for o Leads to voluntary response bias and/or nonresponse bias 3 Naturalistic Observation ● Naturalistic Observation: observing participants in their natural habitats without interacting with them o Positives: gets a realistic and rich picture of the participants’ behavior o Negatives: Control is sacrificed Case Studies ● Case Study: used to get a full, detailed picture of one participant or a small group of participants o Positives: unique situations, foundational to later studies o Negatives: findings can’t be generalized to a larger population APA Ethical Guidelines ● Institutional Review Board (IRB): any type of academic research must first propose the study to this ethics board o Animal research: ▪ They must have a clear scientific purpose (research must answer a specific and important scientific question, animals must be the best way to answer it) ▪ Must care for and house animals in a humane way ▪ Must acquire animal subjects legally ▪ Must design experimental procedures that employ the least amount of suffering feasible o Human Research ▪ No coercion (participation must be voluntary) ▪ Informed consent (participants must know that they are involved in research and give consent, little to no deception) ▪ Anonymity/confidentiality (identity and actions of participants can’t be revealed, can’t identify participants as the source of any of the data) ▪ Risk (participants can’t be placed at significant mental/physical risk) 4 ▪ Debriefing procedures (participants must be told the purpose of the study and provided with ways to contact the researchers about study results) 5