INDIVIDUAL SERIES

In this series, each type of value is shown separately. Groups or Classes are not formed. Individual Series has only one column and that is the observations. There is no column for frequency. All the observations have a frequency of 1.

DISCRETE SERIES

It is also called Ungrouped Frequency Distribution. Discrete Series are shown on the basis of definite/discrete values. There is more than one frequency for each item. Different values of the variables are shown with their respective frequencies. A discrete variable does not take a fractional value but takes just definite integral values. 

CONTINUOUS SERIES

It is also called Grouped Frequency Distribution. A continuous series is one which the different values of the variables are stated in a continuous manner along with their respective frequencies. The classes are formed from beginning to end, without any breaks. Such series can be stated either in the form Inclusive or Exclusive.

Inclusive Series

In this type of series, the upper limit of the class interval is included in the class itself. The class does not overlap.

Exclusive Series

In this type of series, the upper limit of the class interval is excluded from the class itself and is included in the next class.