Suppose you have two individual cross-sectional data sets on car prices for the years 2002 and 2004 covering the time periods both before and after the U.S. invasion of Iraq in 2003. You have 60 observations in your 2002 data set and 60 observations in your 2004 data set. You have decided to append your two individual cross-sectional data sets together to form one pooled cross-sectional data set.
After appending the two data sets, you now have____total observations in your new pooled cross-sectional data set. What are the primary advantages of pooled cross-sectional data over ordinary cross-sectional data?
a. Pooling cross sections enables you to observe changes in key relationships over time.
b. Pooling cross sections enables you to form a panel data set.
c. Pooling cross sections provides a larger sample size.
d. Pooling cross sections enables you to ignore the differences in data over time, since you are left with just one cross-sectional data set.
While similar in some respects, the key difference between panel data and pooled cross-sectional data is that pooled cross sections generally consist of____individual cross-sectional units that are tracked over time. This is not the case with panel data. Which of the following is true regarding panel (longitudinal) data sets?
a. These are more difficult to obtain than other types of data because they require following the same cross-sectional members over a period of time.
b. They are easier to obtain than other types of data because they use the same cross-sectional members over a small time period.
c. Panel data sets enable researchers to see the effects of a policy decision.
d. They do not track the same cross-sectional members over a period of time.