Environmental Decisionmaking

Problem Set #1:

1) (5 pts) Find data on changes in US population over the last few decades, and use information about the recent growth rate, and the historical change in growth rate, to predict population in 2103.

2) (5 pts) Find similar data by age cohort (i.e. what are rates for giving birth and dying for individuals aged 0-10, 11-20, 21-30, etc.). Use this data to construct a spreadsheet model for population every 10 years until the year 2103. You may assume that the immigration rate is the same for all age cohorts, and that death rates are 100% for the last age cohort.

3) (5 pts) Discuss your models. Do you think they represent good estimates for US population in the next 10 years? 40? 100? Why or why not? Is anything significant missing from them? Can you think of a way to add this to your models? (Doing so would be looked upon favorably).

4) (3 pts) The second model was significantly more complex than the first. Was anything gained by including the extra complexity?

5) (2 pts) Look up a population projection on the web. How does this compare with your simple models?