Panel data

A combination of time series data and crossectional data is called panel data. The panel data is also called longitudinal data.

Different types of panel data

Balanced panel data

An equal number of observations for each entire period is called balance panel data

Micro or short panel data:

The number of firms is more than the number of periods.

Macro or long panel data:

The number of periods is more than the number of firms.

Unbalanced panel data:

The number of observations is not the same for all subjects (firm, variable, etc.)