FLEXIBILITY IN DESIGN - Title Page - MIT

de Neufville + Scholtes D R A F T September 30, 2009Box 2.7_____________________________________________________________________________Ambiguous analysis of causes of trendsA regular classroom exercise at MIT involves working with extensive historical data on traffic inLos Angeles. The purpose is to explore how the experts on the actual job arrived at theirforecasts from this data. One phase of the exercise considers the expert analysis that selectedthe relative importance of population and income as drivers of traffic growth, based on whichcombinations matched the historical data most closely.The class exercise invites the students to match the Los Angeles data with any othersingle factor. In recent years the factors that most closely matched the data, and in each case didso much better than the model used by the consultants for Los Angeles, were the:• Divorces in France,• Egg production in New Zealand, and• Prison population of the State of Oregon!Of course, this is all nonsense. That is the point of the exercise. By themselves, good statisticalmatches of annual data means very little, if anything, and it is unrealistic to use these proceduresto develop and select useful forecasts._____________________________________________________________________________Part 1: Chapters 1 to 3 Page 38 of 69