Research Methods

cultural norms

shared rules for acceptable behavior within a culture; influence how people are expected to think, feel, & behave

confirmation bias

tendency to seek & interpret information that supports existing beliefs

hindsight bias

tendency to believe that outcome was predictable AFTER it has happened

overconfidence

tendency to overestimate the accuracy of knowledge, judgments, or abilities

Case study, Naturalistic observation, Meta-analysis, Correlation, Experiment

Types of research in psychology (5)

case study

type of research that is a detailed investigations of one individual, group, or event

naturalistic observation

type of research that observes & records behavior in its setting

meta-analysis

type of research that combines & analyzes results from multiple studies on same topic to identify overall patterns

correlations

type of research that measures the relationship between variables regarding strength & direction

scatterplot

graph used in correlation to show the relationship between two variables

positive correlation

two variables move in the same direction; as one increases, so does the other

negative correlation

two variables move in opposite directions; as one increases, the other decreases

zero correlation

no consistent relationship between two variables

correlation coefficient (r)

statistical index of the relationship between two variables (from -1.0 to +1.0)

third variable

unmeasured variable that produces changes in both variables being studied

illusory correlations

false perception of a relationship where none exists

correlation ≠ causation

just because two variables seem to be related, does not cause & effect can be established

experiment (experimental methodology)

research method that can determine cause-and-effect by manipulating variables

independent variable (IV)

factor that is deliberately manipulated by the researcher to observe its effects

dependent variable (DV)

factor that is being measured as the result of changed independent variable

confounding variables

uncontrolled variables that may impact the DV by distorting the effects of IV

operational definition

clear, measurable definition of a variable in a study

experimental group

group that receives the treatment being tested

control group

group that does not receive the treatment being tested; used for comparison

random assignment

participants are randomly placed into either experimental or control groups

placebo

inactive substance that looks like the actual treatment

hypothesis

specific, testable prediction regarding the relationship between variables

falsifiable

capable of being proven wrong through evidence

population (target population)

entire group of individuals researchers want to study

sample

participants selected to represent the larger population in the study

representative sample

sample that accurately reflects the characteristics of the larger population, in terms relevant demographics

random sampling

every member of population has equal chance of being selected as a participant

convenience sampling

participants are selected because they are easily available

sampling bias

a flaw that occurs when procedure favors the selection of certain members of population over others

generalizability

extent to which results can be applied to larger population beyond the sample used

single-blind

participants do not know which experimental condition (experimental or control) they are in, but researchers do

double-blind

neither participants nor researchers knows which condition participants are in

experimenter bias

researcher's expectations unintentionally influence participants' behavior or interpretation of data

social desirability bias

participants respond in ways they believe are more acceptable to others, rather than responding honestly

qualitative measures

descriptive, non-numerical data that focus on thoughts & feelings

structured interview

same predetermined questions asked in same order so that responses can be compared

quantitative measures

numerical data that can be measured and analyzed statistically

Likert Scale

rating scale used to measure opinions by indicating the level of agreement with a statement (1 = strongly disagree to 5 = strongly agree)

surveys

technique that uses questionnaires or interviews to collect self-reported data from a large group

self-report bias

tendency for people to provide inaccurate or distorted information about oneself

peer review

process in which other experts evaluate the study's methods, data, analyses & conclusion before publication

replication

study is conducted again, following same methodology, to verify original findings

mean

arithmetic average of a distribution

median

middle score in a distribution; half the scores are above it and half are below it

mode

most frequently occurring score in a distribution

range

difference between the highest and lowest scores in a distribution

standard deviation

measure of variability, or how scores typically vary from the mean

percentile rank

percentage of scores at or below a particular score

normal curve

symmetrical, bell-shaped distribution of scores; most scores cluster around mean & frequencies of scores decrease as they move away from mean

68-95-99.7 rule

in a normal distribution, the percentage of scores that fall within each standard deviation

skewed distribution

asymmetrical distribution with a longer tail on one side

bimodal distribution

distribution that contains two distinct peaks suggesting that data may come from two different subgroups

regression toward the mean

tendency for extreme scores to be followed by scores closer to the average when measured again

effect size

measures the magnitude of a difference or relationship (between variables or groups)

statistical significance

indicates the likelihood that the result is not due to chance alone

null hypothesis (H0)

statement of "no statistical difference" between the variables being studied

institutional review, informed consent/assent, protection from harm, confidentiality/anonymity, debriefing

ethical considerations

institutional review

process of examining & overseeing studies for ethical treatment of participants

informed consent

voluntary agreement to participate in research after receiving information about it

informed assent

agreement to participate from individuals who cannot legally provide informed consent like minors

protection from harm

expectation that participants should not be put through anything that would cause physical or psychological damage

confidentiality

practice of keeping personal data gathered from research private & secure

deception

intentionally misleading or withholding information about the study from participants

research confederates

individuals working with researchers who pretend to be ordinary participants or bystanders

debriefing

informing participants the true purpose of research and of any deception used, after completion