AP Psych; Research Methods Vocab

hindsight bias

the tendency to believe, after learning an outcome, that one would have foreseen it

double blind procedure

an experimental procedure in which both the research participants and the research staff are ignorant about whether the research participants have received the treatment or a placebo. commonly used in drug-evaluation studies

independent variable

the experimental factor that is manipulated -- the variable whose effect is being studied

dependent variables

the outcome factor -- the variable that may change in response to manipulations of the independent variable

mode

the most frequent occurring score(s) in a distribution

mean

the arithmetic average of a distribution, obtaining by adding the scores and then dividing by the number of scores

median

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

standard deviations

a computed measure of how much scores vary around the mean score

random assignment

assigning participants to experimental and control conditions by chance, thus minimizing preexisting differences between those assigned to the different groups

random sampling

a sample that fairly represents a population because each member has an equal chance of inclusion

scatter plot

a graphed cluster of dots, data shows correlation or the direction of relationship between two variables

illusory correlation

the perception of a relationship where none exists

case study

an observation technique in which one person is studied in depth in the hope of revealing universal principles

survey

a technique for ascertaining the self-reported attitudes or behaviors of people, usually by questioning a representative, random sample of them

naturalistic observation

observing and recording behavior in naturally occurring situations without trying to manipulate and control the situation

correlation

a measure of the extent to which two factors vary together, and thus of how well either factor predicts the other. the correlation coefficient is the mathematical expression of the relationship, ranging from -1 to +1

experiment

a research method in which an investigator manipulates one or more factors (ind. variables and dep. variables) to observe the effects on some behavior or mental processes.

replication

repeating the essence of a research study, usually with different participants in different situations, to see whether the basic finding extends to other participants and circumstances

statistical significance

a statistical statement of how likely it is that an obtained result occurred by chance

operational definition

a statement of the procedures used to define research variables. ex -- human intelligence, what an intelligence test measures

critical thinking

thinking that does not blindly accept arguments and conclusions. rather, it examines assumptions, discerns hidden values, evaluates evidence, and assesses conclusions

theory

an explanation using the integrated set of principles that organizes and predicts observations

hypothesis

a testable prediction, often implied by a theory

population

all the cases in a group, from which samples may be drawn for a study

sample

items selected at random from a population and used to test hypotheses about the population

confounding variable

a factor other than the independent variable that might produce an effect in an experiment

range

the difference between the highest and lowest scores in a distribution

normal curve/distribution

a symmetrical, bell-shaped curve that describes the distribution of many types of data; most scores fall near the mean, and fewer near the extremes

inferential statistics

numerical methods used to determine whether research data support a hypothesis or whether results were due to chance

informed consent

an ethical principle requiring that research participants be told enough to enable them to choose whether they wish to participate

debriefing

the post-experimental explanation of a study, including its purpose and any deceptions to its participants