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hindsight bias

the tendency to believe, after learning learning an outcome that one would have seen it (the i knew it all along phenomenon)

Amazing Randi

The magician that exemplifies skepticism. Disproves psychics.

Theory

an explanation using an integrated set of principals that organizes and predicts observations

hypothesis

a testable predictions, often implied by theory

Operational definitions

a statement of the procedures used to define research variables

replicate

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

false consensus effect

the tendency to overestimate the extent to which others share our beliefs and behaviors

population

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

random sample

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

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 situations

correlate

a measure of the extent to which two factors vary together and thus of how well either factor predicts the other

correlation coefficient

a statistic representing how closely two variables co-vary

scatterplots

a graphed cluster of dots, each of which represents the values of two variables. The slope of the points suggest the direction of the relationship between the two variables. The amount of scatter suggest the strength of the correlation

illusory correlations

the perception of a relationship where none exists

experiment

a research method in which an investigator manipulates one or more factors (independent variables) to observe the effect on some behavior or mental process (the dependent variable). By random assignment of participants, the experimenter aims to control other relevant factors.

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 placebo

Mamie Phipps Clark

studied the effects of segregation and racism on the self-esteem of black children. Her work with her husband, Dr. Kenneth Clark, was used in testimony in the case of Brown V. The Board of Education

Kenneth B. Clark

studied segregation on children

Hawthorne Effect

phenomenon in which participants' knowledge that they're being studied can affect their behavior

Placebo Effect

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

experimental condition (group)

the condition of an experiment that exposes participants to the treatment, that is, to one version of the independent variable

control condition (group)

the condition of an experiment that contrasts with the experimental condition and serves as a comparison for evaluating the effect of the treatment

random assignment

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

independent variable

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

dependent variable

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

confounding variable

extraneous factor that interferes with the action of the independent variable on the dependent variable

experimental ethics

For an experiment to be ethical (for humans) it needs consent, no harm, anonymity, and a debriefing. For animals it can't be prolonged pain.

measures of central tendency

mean, median, mode

mean

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

median

the arithmetic average of a distribution; half the scores are above it and half are below it

mode

the most frequently occurring score(s) in a distribution

range

the difference between the highest and the lowest scores in a distribution

standard deviation

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

z- score

distance from the mean in units of standard deviation

p- value

probability of an alignment occuring with the score in question or better. A different way of representing the significance of alignmnet; significant P scores will be close to 0.

frequency distribution

a distribution of observed frequencies of occurrence of the values of a variable