Complete LUKO UNIT 2

hindsight bias

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

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 an integrated set of principles that organizes and predicts observations

hypothesis

a testable prediction, often implied by a theory

operational definition

carefully worded statement of the exact procedures used research study. Ex human intelligence -- what an intelligence test measures.

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

case study

descriptive technique in which one individual or group is studied in depth in the hope of revealing universal principles

naturalistic observation

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

survey

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

sampling bias

flawed sampling process that produces an unrepresentative sample

population

all those in a group being studies, from which samples may be drawn

random sample

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

correlation

measure of the extent to which two variables change together, and thus of how well either variable predicts the other

correlation coefficient

statistical index of the relationship between two variables. (from -1 to +1)

scatter plot

graphed cluster of dots, each of which represents the values of 2 variables. Slope of points suggests direction of relationship between the two variables. Amount of scatter suggests strength of correlation

illusory correlation

perception of a relationship where none exists

experimental group

in an experiment, the group exposed to treatment, that is, to one version of the independent variable.

control group

in an experiment, the group not exposed to treatment; contrasts with the experimental group and serves as a comparison for evaluating effect of the treatment

experiment

research method in which an investigator manipulates one or more factors (independent) to observe effect on some behavior or mental process (dependent)

random assignment

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

double blind procedure

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

placebo

experimental results caused by expectations alone; any effect on behavior caused by the administration of an inert substance or condition, which the recipient assumes is an active agent

independent variable

experimental factor that is manipulated; variable whose effect is being studied

confounding variable

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

dependent variable

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

most frequently occurring score(s) in a distribution

mean

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

median

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

range

difference between highest and lowest scores in a distribution

standard deviations

computed measure of how much scores vary around the mean score

normal curve

(distribution) symmetrical, bell-shaped curve that describes the distribution of many types of data; most scores fall near the mean (68% fall within one standard deviation of it) and fewer near the extremes

statistical significance

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

informed consent

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

debriefing

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

Hawthorne Effect

People may change the way they act because they know they are being watched for an experiment

Longitudinal Study

One group of subjects are followed and observed for an extended period of time

Cross-sectional study

Examines a representative cross-section of the population and tests/surveys these subjects at one specific time