research methods data glossary

correlation

mathematical technique in which a researcher investigates an association between two variables (covariables)

co variable

variables investigated within a correlation

positive correlation

as one variable changes, the other also changes in the same direction

negative correlation

as one variable changes, the other changes in the opposite direction.

zero correlation

when there is no relationship between the co-variables

qualitative data

descriptive data expressed in words

quantitative data

data that is expressed as numbers

primary data

info that has been obtained first hand by a researcher for the purposes of the research

secondary data

info that has been already collected by someone else and predates the current research project.

meta-analysis

the process of combining the findings of a number of studies on a particular topic

central tendency

any measure of the average value in a set of data

mean

arithmetic average

median

central value in a set of data

mode

most frequently occurring value in a data set

dispersion

a measure of the spread of a set of data

range

largest value subtract the lowest value

standard deviation

how much, on average, each score deviates from the mean

scattergram

a type of graph that shows the relationship of two co-variables in a correlation analysis

bar chart

a type of graph in which the frequency of each variable is shown throuhg the height of the bars

histogram

a type of graph that shows the frequency by the area of the bar

normal distribution

a symmetrical spread of frequency data

skewed distribution

a spread of frequency data that is not symmetrical

positive skew

a type of frequency distribution in which the long tail is on the right side of the graph

negative skew

a type of frequency distribution in which the long tail is on the left side of the graph