Classes

Equal classes

The standard option is to have classes of equal width.

If you change the number of classes, the lower bounds change accordingly.

If you change the boundaries, the number of classes does not change. It might then happen that a graph or table only presents a part of the data. In this case a warning is given.

Unequal classes

It is possible to work with classes of different widths.

With unequal classes you must enter the class boundaries. The final number is the upper bound of the final interval.

If a bar chart is produced, the vertical scale will be “frequency density” and the bars will be of different widths, corresponding to your classes.