PORTLAND, Ore.—When it comes to predicting the future, Moore's Law has been a time-worn bell-weather. But did you know its just one of several competing laws with names like Sinclair-Klepper-Cohen's, Goddard's and Wright's Law?
Overall the best long-term predictor is Wright's Law, which improves its accuracy over Moore's law by framing its horizon in terms of units-of-production instead of absolute time. For instance, Moore's Law predicts that every 18 months the density of semiconductors will double, whereas Wright's Law predicts that as the number of units manufactured increases the cost-of-production decreases (no matter how long that might take). Thus Wright's Law--named after aeronautical engineer, Theodore "T.P." Wright--offers more accurate long-term predictions since it automatically adapts to economic growth rates.
Growth of prediction errors for competing laws to Moore's Law shows Wright's Law the best at long-time horizons, Goddard's Law as the worse at short time horizons, and Sinclair-Klepper-Cohen the worst for long-time horizons.
Wright's and other alternatives, such as Goddard's (which postulates that progress is driven only by economies of scale) and Sinclair-Klepper-Cohen's (which combines Wright's and Goddard's), were compared to the actual cost and production units in 62 different technologies, including computers, communications systems, solar cells, aircraft and automobiles. Historical data allowed accurate comparisons using "hind-casting" whereby a statistical model was developed to rank the performance of each postulated law over time.
MIT claims its results show that with careful use of historical data, future technological progress is forecastable with a typical accuracy of about 2.5 percent per year. The research was conducted by MIT professor Jessika Trancik, professor Bela Nagy at the Santa Fe Institute, professor Doyne Farmer at the University of Oxford and and professor Quan Bui at St. JohnÕs College (Santa Fe, N.M.).
Two criticisms: 1) Wright's law is worthless as a prediction; it is parametric in units. You need the prediction in time. So I have to have an Oracle predictor of units over time, and if I have that, who needs Wright? Not surprised it came out best in "hindcasting".
2) With Moore's Law, don't confuse cause and effect. Moore's Law is not an immutable cause. It was the target to which the semiconductor industry managed itself to, thus, get the doubling effect.