chapter 2: psychological research

theory

well developed set of ideas that propose an explanation for observed phenomena

hypothesis

tentative and testable statement about the relationship between between two or more variables

deductive reasoning

conclusions are drawn based on a general premise, based on logical analysis

inductive reasoning

conclusions are drawn based on empirical observations

case studies

focus on one individual, extreme or unique psychological circumstances

pro: in depth exploration

con: difficult to generalize population

naturalistic observation

observation of a behavior in its actual setting

observer bias

observations may be skewed to align with observers expectations

surveys

• list of questions

• huge amounts of data from large population

• pro: info from lots of people

• con: people may lie

archival research

uses past records or databases

pro: data already collected

con: can’t change what info is available

cross sectional research

comparing multiple groups at a single point in time

longitudinal research

multiple measurements from the same group of people over time; risks attritions

attrition

subjects dropping out of a study over time

correlation

relationship between two or more variables, one variable changes alongside another

correlation coefficient

-1 to +1, indicates strength and direction of correlation, R

negative correlation

two variables change in different directions

postive correlation

two variables change in the same direction

scatterplots

graphical view of the strength and direction of correlations

cause and effect relationship

changes in one variable cause changes in another; can only determined by experimental research design

confounding variable

outside factor that affects both variables on interest; gives impression that changes in one variable cause changes in the other

experimental group

the participants that experience the manipulated variable

control group

participants that do not experience the manipulated variable

experimenter bias

researchers’ expectations skew the results

participant bias

participants’ expectations skew the results (ex placebo)

single blind

participants don’t know what group they’re in

double blind

participants and researchers who directly interact with participants don’t know who is in which group

variable

characteristic on which subjects can vary

independent variable

something researchers may directly control in an experiment

dependent variable

something you measure in a subject that may be influenced by the independent variable

random sampling

“gold standard”; ensures representation and prevents bias

statistically significant

if data is very unlikely to just have happened by chance

peer reviewed journals

• other scientists with knowledge on the study’s topic

• give anonymous feedback on study quality and impact

• quality control and improvement of research

reliable

consistent over time and across situations/raters

valid

measuring what it truly intends to measure

institutional review boards (IRBs)

• human subjects research

• check for informed consent

• check for risks vs benefits to participant

institutional animal care and use committee (IACUC)

check for humane treatment of animals