Basic Functionalities

Different people will do different things with IFs. In general those activities fall into four categories of functionality:

• Display: This mode allows users to display results of runs of the model, normally starting with extended exploration of the base case of the model. The base case helps show the character of the world today (size of populations, economies, energy use, etc.) and to examine the patterns and trends of development as captured in the base case of the model.
• Scenario Analysis: IFs allows users to create and display alternative scenarios about the future other than the base case in order to explore a range of uncertainty or to consider policy leverage. Quick Scenario Analysis with Tree is a tool used to alter parameters and initial conditions that drive different variables within the IFs system.
• Data Analysis: It is possible to create maps for geographic comparison and to undertake longitudinal or cross-sectional analysis of the extensive database within IFs to explore historical trends and relationships. This mode also allows users to view hundreds of the computed functions and relationships that underpin the IFs model as well as to learn about how to see which countries are members of which groups in the country data in IFs.
• Learning about the Model: The more one uses IFs, the more important it becomes to understand what lies "under the hood" or, as modelers often say, "inside the black box." The Help option of IFs assists you not only in using the model, but in exploring each sub-module through a variety of steps proceeding from verbal description through flow charts to equations.

The structure of following chapters and topics in this Help system corresponds generally to these function sets.