Frequency Tables:

The frequency of any value of any variable is the number of times that value occurs in the data. In other words, a frequency is a count.

The relative frequency of any value is the proportion or fraction or percent of all observations that have that value.

Data are univariate when only one variable is measured on each unit.

Data are bivariate when two variables are measured on each unit.

Data are multi-variate when more than one variable is measured on each unit.

Graphs:

1. Line graphs - show the trend of a variable over time.

2. Bar graphs - compare the values of several variables. Often the values compared are frequencies or relative frequencies of outcomes of a nominal variable.

3. Scatter plots - graph bivariate data when both variables are measured in an interval/ratio or ordinal scale. Units for one variable are marked on the horizontal axis, and units for the other on the vertical axis. The independent variable should always go on the horizontal axis when one of the variables is an independent and one a dependent variable.

In general, research is theory oriented, and evaluation is outcome oriented.