FLEXIBILITY IN DESIGN - Title Page - MIT

de Neufville + Scholtes D R A F T September 30, 2009• The International Energy Agency (200X)provides energy forecasts, indicating for examplethat “Demand for oil rises from 85 million barrels per day now to 106 mb/d in 2030” ;• The US Energy Information Administration (200x)predicts that wind energy production inthe United States will rise from 24.81 gigawatts in 2008 to 42.14 in 2030;• Gartner Inc. (2005) forecast the future sales of cells phones in the USA as“By 2009 the basic smart phone category will grow by 44.9 percent to 180.2 million units,while enhanced smart phones will grow by 67.9 percent to 98.5 million units”Such highly precise forecasts are not credible. The most skilled technicians, usingsophisticated scientific instruments, operating in tightly controlled laboratories, would be fortunateto achieve such levels of accuracy in measuring known substances. Estimates of what mighthappen, in the messy real world, years ahead, cannot be anywhere near this good. If we arelucky, our predictions might be within a few percent of eventual reality – optimistically, the first twofigures of the forecast might be correct.Yet the common feature for almost all point forecasts is that they provide no indication oftheir uncertainty, let alone of the degree of confidence we will have in them. They do not suggestthe real possibility – the almost certainty -- that actual situations may be very different from theforecasts. The point forecasts are thus misleading. In fact, as shown below, there are typicallylarge gaps between the point forecasts and what actually occurs.[Box 2.2 about here]Specialized professionals. Another important feature of standard practice is the way it is done.Specialized professionals usually manage the process of forecasting. They typically work inseparate agencies or companies, distinct from the designers or planners for the systems underconsideration. For example:• Economists and statisticians develop models to predict the future levels of air traffic.• Market analysts use consumer surveys and focus groups to define future sales ofautomobiles.• Geologists develop best estimates of the size of oil fields, which they hand over to thestructural and other engineers designing oil platforms.In short, there is a great professional distance between the producers of the forecasts and thosethat will use these figures for design. Physical and institutional distance between these groupsfurthermore reinforces this separation.This separation of tasks conveniently shifts responsibilities and provides convenientexcuses for design professionals. If their product does not meet the actual demands, they canfeel absolved of responsibility. They can argue that they did what they were told to do, and cannotbe responsible for the mistakes of the forecasters – who are conveniently in some otherPart 1: Chapters 1 to 3 Page 25 of 69