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APA ethical guidelines

1. No Harm
2. Privacy and confidentiality
3. Institutional Approval
4. Competence
5. Record Keeping
6. Informed consent to research
7. Dispensing with Informed Consent
8. Offering Inducements for Research Participation
9. Deception in Research
10. Debriefing


The mathematical average of a set of numbers.


Denoting or relating to a value or quantity lying at the midpoint of a frequency distribution of observed values or quantities


The number that appears most often in a frequency distribution of observed values or quantities

Correlational coeffiecient

a measure of how well trends in the predicted values follow trends in past actual values.

cross sectional

form a class of research methods that involve observation of all of a population, or a representative subset, at one specific point in time. They differ from case-control studies in that they aim to provide data on the entire population under study, whereas case-control studies typically include only individuals with a specific characteristic, with a sample, often a tiny minority, of the rest of the population.

Dependent variable

Variable being measured

Double blind

Double-blind describes an especially stringent way of conducting an experiment, usually on human subjects, in an attempt to eliminate subjective bias on the part of both experimental subjects and the experimenters.

fixed interval

a schedule of reinforcement where the first response is rewarded only after a specified amount of time has elapsed. This schedule causes high amounts of responding near the end of the interval, but much slower responding immediately after the delivery of the reinforcer.


Schedules of reinforcement have a major impact on how fast a behavior is acquired and the strength of the response.

illusory correlation

the phenomenon of seeing the relationship one expects in a set of data even when no such relationship exists.

independent variable

the variable that is varied or manipulated by the researcher

informed consent

a phrase often used in law to indicate that the consent a person gives meets certain minimum standards.


a correlational research study that involves repeated observations of the same variables over long periods of time — often many decades. It is a type of observational study. Longitudinal studies are often used in psychology to study developmental trends across the life span, and in sociology to study life events throughout lifetimes or generations.

Negative correlation

A relationship between two variables in which one variable increases as the other decreases, and vice versa. In statistics, a perfect negative correlation is represented by the value -1.00, while a 0.00 indicates no correlation and a +1.00 indicates a perfect positive correlation.

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placebo effect

The placebo effect happens when you decide a therapy will make you better and your belief makes it so.

Positive correlation

A relationship between two variables in which one variable increases as the other decreases


reliability refers to the consistency of a measure. A test is considered reliable if we get the same result repeatedly. For example, if a test is designed to measure a trait (such as introversion), then each time the test is administered to a subject, the results should be approximately the same.

standard deviation

a measure of how spread out numbers are.


Validity is whether the construct you are using really measures what you are using it to measure. For example, if you devised a test to measure people's self-esteem, does it really measure self-esteem, or something similar such as extraversion?


the variance of a random variable is a measure of its statistical dispersion, indicating how far from the expected value its values typically are. The variance of a real-valued random variable is its second central moment, and it also happens to be its second cumulant. The variance of a random variable is the square of its standard deviation.

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