Knowing common research terminology helps you understand how to read and interpret scholarly journal articles so you can more effectively apply the results to real world human performance. The following are basic research terms and definitions.

**abstract**----a brief overview of
a research study

**constitutive definition**--the basic, dictionary meaning

**construct**--a term that describes a
human variable that is not directly measurable (e.g., motivation, self esteem). Also known as a psychological construct

**control group**--in experiments, the one that doesn't get the
treatment

**correlational study**--a type of research design that depicts a
relationship between variables, but not necessarily one of cause-effect

**data**--information. can be numbers or words. plural form of datum.
the "data show" not "shows"

**dependent variable**--the quality you are observing

**descriptive study--**research design that describes "what is" (e.g., a survey)

**experiment**--a research design used to find
"cause-effect" relationships. the "effect of...on..". lots
of variations. top shelf in research

**experimental group**--the one that get the treatment

**external validity**--how generalizable the results are outside of
the study as it concerns other populations and locations.

**further study is needed**--we don't know

**independent variable**--the one you are manipulating. The effect of
(independent, such as training method) on....

**internal validity**--the extent to which a study measures
what it is supposed to (accuracy within the study)

**measures of central tendency**--averages; e.g., the mean

**measures of variability**--spread; e.g., standard deviation

**mean**--the arithmetic average

**median**--the middle where half the scores fall above, half below.
eliminates the influence of outliers

**mode**--the score that occurs most

**no evidence**--we don't know, haven't figured out how to attack the
problem, or haven't cared enough to try

**operational definition**--how a term is used in a study.

**population**--all of a group of interest

**prove**--not used in research about human performance. could result
in a shunning

**random**--by chance

**random sample**--everybody had the same chance of being assigned to
any group. sometimes confused with who you ran into by chance

**research**--a systematic, objective way to generate facts or knowledge

**research design**--the game plan or method for finding out what you
want to know. experiments, correlations, descriptive studies

**sample--**a smaller group that represents a population of interest

**significance**--two meanings: significance of the study means why it
is importance. Also see **statistical significance**

**standard deviation**--a measure of spread. the average deviation of
a group of scores from the mean

**statistical significance**--an important finding that did not likely
happen by chance. p<.05 means that there were less than 5 chances in 100
that the result would have happened randomly

**statistics**--mathematical tools based on the normal curve used to
analyze data. researchers must match statistics with research designs

**T-score**--a standard score on the normal curve where the mean is
assigned "50" with deviations of "10". Allows more simple
interpretation of student achievement.

**t-test**--a parametric statistical tool that compares differences
between the means of two groups; assumptions for use include normal
distribution and at least interval data.

**the extent to which**--a favorite phrase of researchers that means
"how much". implies ranges and probabilities and avoids absolutes

**validity**----accuracy. the extent to which a test or study measures
what it is supposed to measure

**variable**----a quality of interest that can be manipulated or
observed.

**z-score**--a standard
score on the normal curve. Each z-score is counted as "1" from the
mean, plus or minus.