Panel Data - Example

Example

balanced panel: unbalanced panel:
\begin{matrix}
\mathrm{person} & \mathrm{year} & \mathrm{income} & \mathrm{age} & \mathrm{sex}\\
1 & 2003 & 1500 & 27 & 1 \\
1 & 2004 & 1700 & 28 & 1 \\
1 & 2005 & 2000 & 29 & 1 \\
2 & 2003 & 2100 & 41 & 2 \\
2 & 2004 & 2100 & 42 & 2 \\
2 & 2005 & 2200 & 43 & 2
\end{matrix} \begin{matrix}
\mathrm{person} & \mathrm{year} & \mathrm{income} & \mathrm{age} & \mathrm{sex}\\
1 & 2003 & 1500 & 27 & 1 \\
1 & 2004 & 1700 & 28 & 1 \\
2 & 2003 & 2100 & 41 & 2 \\
2 & 2004 & 2100 & 42 & 2 \\
2 & 2005 & 2200 & 43 & 2 \\
3 & 2004 & 3000 & 35 & 1
\end{matrix}

In the example above, two data sets with a two-dimensional panel structure are shown, although the second data set might be a three-dimensional structure since it has three people. Individual characteristics (income, age, sex. educ) are collected for different persons and different years. In the left data set two persons (1, 2) are observed over three years (2003, 2004, 2005). Because each person is observed every year, the left-hand data set is called a balanced panel, whereas the data set on the right hand is called an unbalanced panel, since Person 1 is not observed in year 2005 and Person 3 is not observed in 2003 or 2005.

Read more about this topic:  Panel Data

Famous quotes containing the word example:

    Our intellect is not the most subtle, the most powerful, the most appropriate, instrument for revealing the truth. It is life that, little by little, example by example, permits us to see that what is most important to our heart, or to our mind, is learned not by reasoning but through other agencies. Then it is that the intellect, observing their superiority, abdicates its control to them upon reasoned grounds and agrees to become their collaborator and lackey.
    Marcel Proust (1871–1922)