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Populate ©Robert McCaa, Department of History and University of Minnesota Population Center | ||||||||||||||||||||||||||||||
| Populate...
easily, quickly and accurately carries out the calculations of inverse projection. I recommend it to anybody wishing to use inverse projection. --Ronald D. Lee, Graduate Group in Demography University of California (Berkeley) "Methods and Models in Macro-Demographic History: An Update and Assessment" in Old and New Methods in Historical Demography (Oxford University Press, 1993.) | ||||||||||||||||||||||||||||||
Introduction | ||||||||||||||||||||||||||||||
| Peruse this guide | Populate is designed to be used with only a quick perusal of this guide. A bit of reading will be rewarded by a better understanding of the operation of the program as well as the features and strengths of the inverse projection method. | |||||||||||||||||||||||||||||
| To Populate | To put Populate on the desktop: To start from the desktop, simply click the MS-DOS icon "populate.com" | |||||||||||||||||||||||||||||
| Speed Populating | A speedy way to learn the program is to open Windows Explorer and click Populate. The opening screen (Figure 1) offers three choices. Tap "E" to look at an example using data for England (1541-1871), tap "H" for Help, that is an introduction to Populate, or tap <enter> (or any other key) to enter a datafile name. Figure 1 | Opening Screen
P O P U L A T E(c) | Inverse Projection: Population Rates, Life Expectancy, Reproduction Ratios, and Age Structure (c)Copyright 1986, 1989, 1991, 2001 R. McCaa and Hector Perez Brignoli University of Minnesota Population Center Social Sciences 614, Minneapolis, MN 55455 rmccaa@umn.edu Thanks to Project WOKSAPE The University of Minnesota and International Business Machines Corporation P O P U L A T E(c) Version 2.9 April 14, 1991 Tap E for an Example, H = Help, or <enter> Menus |
Menus drive the program (see command line at the bottom of each Populate screen). To activate a command or select a feature, simply tap the first letter (hotkey) of words appearing on the command line at the bottom of the screen. Descriptive command names help the beginner or infrequent user to obtain results easily. | Why Populate? | What can counts of births and deaths reveal about life expectancy, fertility, age structure or population size? A lot! Populate computes population size, life expectancy, reproduction ratios, and even age structure, when estimates of births and deaths are the only data at hand. Based on Ronald Lee's inverse method of population projection, Populate uses real data--whenever possible--and fills in with information from models--when necessary--to compute population censuses at five year intervals. Once a projection is complete, the program makes it possible to quickly construct alternative scenarios by simply querying: what if...conditions were different? Populate answers with sets of demographic estimates enticed from a time series of births and deaths under varying assumptions--all easily specified according to what you know or are willing to guess. | Uncertainty and flexibility | Lee's method of projection requires that assumptions be made about the size of the initial population and its age and mortality structure, although not its level. With Populate you can rapidly re-examine estimates by varying one or all assumptions, as well as taking into account migration, birth or death under-registration, and age-specific patterns of fertility or migration. Where knowledge is uncertain--the case for most places before 1900 or, say, a few years into the future--this approach "sacrifices" the accuracy of conventional projection methods for flexibility. Students use the program to develop an understanding of population dynamics, to assess the effects of counterfactuals, or even project populations into the future under various scenarios. Researchers turn to Populate to compute consistent estimates, test data accuracy, and weigh alternative hypotheses about demographic densities and structures. | Demographic snapshots of the past | With Populate, the historian can select among estimates of population size and structure or mortality and fertility to bring a larger picture into focus, expose inconsistencies, and test the frailty of results. Populate helps reveal the impossible and provides tools for making all settings consistent. When the entire picture does not add up, the program's demographics help find out why. | Demographics of the future? | Demographers project, but do not predict. Populate does not predict either, but it does allow futurologists--licensed or not--to specify a set of conditions to see what the world or a piece of it might look like. Authorities often present a single demographic view of the future. This program allows you to imagine what the settings might be, then project to see what difference they might make. When specialists harness sophisticated tools to simple, politically inoffensive, or plainly unrealistic projections, the non-specialist may turn to Populate, trading technical sophistication for simplicity, the inoffensive for intuition, inquisitiveness and intelligence.
| Tutorials | Use tutorials (Learn at the Populate menu) to become familiar with Populate's features. Tap learn, then select a lesson. The tutor will monitor the lesson stroke-by-stroke. New lessons are easily created by simply turning the recorder on and putting the program through its paces. The recordings are saved to disc with the corresponding dataset and are automatically recalled to aid the student in analyzing specific demographic issues. | Vocabulary | The program's vocabulary is limited three types of commands--actions, display options, and statistics (Figure 2)--, totaling 45 words or commands. The meaning of each word is explained in this guide (click here) or may be reviewed while the program is running via its help screens. Chapters 3 and 4, "Composing Models" and "Displays", describe each word in context, and Chapter 7, "Glossary", briefly defines each word in alphabetical order. | Figure 2. |
Program Vocabulary When Populate is running, tap the underlined/capitalized letter to:
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