Included countries are Bulgaria, Czechoslovakia, East Germany, Hungary, Poland, and the Soviet Union. The REIS data base provides local area economic data for states, counties, and metropolitan areas for 1969-1996. The REIS has been conducted annually since 1969. You can search the title of paper and related data sets in the following web site. Before exploring an appropriate data set to a specific research topic, you need to understand the characteristics of time dimensions in social surveys.
Most empirical studies are cross-sectional due to the limits of time and money.
Some well known surveys, such as the General Social Survey and the Current Population Survey , are cross-sectional. One of the main drawbacks of cross-sectional studies is that it is not easy to analyze the causal relationships among variables, especially when the chronological ordering of variables or when tracing the changes of sample populations are critical to research hypotheses. Time-series data are generated and used for longitudinal research designs. And a time series analysis is a statistical method to analyze the changes in certain variables over time. Graph-b presents the concept of trend study.