IFs is a tool for thinking about the future. In addition to exploring the base case and building alternative scenarios thinking about the future requires understanding the past. Moreover, exploration of historic data is a key to evaluating and enhancing the relationships used in IFs and other models for forecasting.

An extensive, country-specific database underlies IFs. It is used for (1) computing the initial conditions for all countries/regions, and (2) investigating relationships between variables as a basis for specifying those relationships within IFs. Lesson 3 introduces you to tools for exploring that database.

Begin at the Main Menu, touch the Data Analysis option and look at the sub-options. These include:

• World Map
• Analyze Across Countries (Cross-Sectional Analysis)
• Analyze Across Time (Longitudinal Analysis)

This lesson gives you a brief introduction to each form of analysis, with pointers to more extended discussion.

World Map

This Data Analysis option allows users to map various sets of historic data on a world map. After you have finished with this topic, you should be able to do/answer the following:

• From the Data Table, which category would you choose if you wanted to display data representing values and norms held by different countries?
• Can you produce a map that separates GDP at PPP out into 6 different categories, each category having the same number of members?
• Can you change the map display? 

Analyze Across Countries (Cross-Sectional Analysis)

This Data Analysis option allows users to access the extensive data base that underlies IFs and statistically compare data sets. After you have finished with this topic, you should be able to do/answer the following:

• Can you select total fertility rate as your dependent variable and GDP at PPP as your independent variable?
• After you have successfully plotted your data, can you export it to Excel?
• What do the data under Primary and Statistics and Secondary Statistics tell you?

Analyze Across Time (Longitudinal Analysis)

This Data Analysis option allows users to access the data base that underlies IFs and compare data sets longitudinally. After you have finished with this topic, you should be able to do/answer the following:

• Select a set of data. How can you display this across time?
• Plot information comparing GDP at PPP with tfrm for one country of your choosing.
• Experiment with one country of interest to you. Choose variable from the World Value Survey as your dependent variable and economic indicators as your independent variable. What do you notice?