Variables

Variable

is a measurable characteristics that varies. It may change from group to group, person to person or within person over time.

Classifications of Variables

Numerical, Categorical, Experimental, & Non-experimental

Numerical Variable

variables with values that describe a measurable numerical quantity.

Continuous/Interval Variable

assume any value between a certain set of real numbers depending on the scale used.

Discrete Variable

can only assume any whole value within the limits of the given variable.

Categorical Variable

Variables with values that describe a quality or characteristic of a data unit.

Ordinal Variable

can take value which can be logically ordered or ranked.

Nominal Variable

values which cannot be organized in a logical sequence.

Dichotomous Variable

variables that represents only two categories.

Polychotomous Variable

variables that have many categories.

Experimental Variables

Variables that determine causal relationships.

Independent Variable

is the condition that you change in experiment. It is the variable you control. It is called independent because its value doesn’t affected by the other variable.

Dependent Variable

is what is affected by the Independent variables. It depends on the values that result from the Independent variables.

Moderating Variable

is one that has strong contingent effect on the Independent & Dependent variable relationship.

Controlled Variable

is the factor that is kept constant (unchanged) all throughout the experiment in order to test the relative relationship of the Independent and dependent variables.

Extraneous Variable

are factors in the research which may have an effect on the Dependent variables but which are not controlled.

Non-experimental Variable

Variables which cannot be manipulated by the researcher.

Predictor Variables

is variables that change or affect other variables in a non-experimental study.

Criterion Variables

is variables that influenced by the predictor variables in a non-experimental study.

Univariate Study

Only one variable is being studied.

Bivariate Study

Two variables are being studied.

Multivariate Study

More than two variables are being studied.

Univariate, Bivariate, & Multivariate Study

VARIABLES according to the number being studied