Classification of Variables

A. According to continuity of values

1. Continuous variables. These are variables that can take the form of decimals.
Example. Weight, length, height, school achievement.

2. Discrete or discontinuous variable. These are variables that can’t take the form of
decimals.
Example: number of students, number of houses, size of a family, etc.

B. According to scale and measurements

1. Nominal variable. This property allows one to make statements of similarities or
differences.
Example: sex- member of population may be classified as male or female,
socio-economic status – the member of the group may be classified
as those belonging to high, average or low socio-economic status

2. Ordinal variable. This variable refers to a property whereby members of a group are
ranked.

Example: one can judge and rank the contestants in a beauty contest.

3. Internal variable. This property allows one to make statements of equality of intervals.

Example: height, weight, temperature, test scores, etc.

4. Ratio variable. This property permits making statements of quality of ratios.

Example: If Cora is 48 yrs. old and Philline is 22 years old. Their ages can be expressed in the ratio of 48:22 or 24:11 (twenty-four is to eleven)

C. According to Functional Relationship

1. Independent variable. This is sometimes termed as predictor variable.

2. Dependent variable. This is sometimes called criterion variable.

Example: Academic achievement is dependent on I.Q . I.Q. is independent variable and academic achievement is the dependent variable