Role of design complexity in technology improvement
Open Access
- 16 May 2011
- journal article
- research article
- Published by Proceedings of the National Academy of Sciences in Proceedings of the National Academy of Sciences of the United States of America
- Vol. 108 (22), 9008-9013
- https://doi.org/10.1073/pnas.1017298108
Abstract
We study a simple model for the evolution of the cost (or more generally the performance) of a technology or production process. The technology can be decomposed into n components, each of which interacts with a cluster of d - 1 other components. Innovation occurs through a series of trial-and-error events, each of which consists of randomly changing the cost of each component in a cluster, and accepting the changes only if the total cost of the cluster is lowered. We show that the relationship between the cost of the whole technology and the number of innovation attempts is asymptotically a power law, matching the functional form often observed for empirical data. The exponent α of the power law depends on the intrinsic difficulty of finding better components, and on what we term the design complexity: the more complex the design, the slower the rate of improvement. Letting d as defined above be the connectivity, in the special case in which the connectivity is constant, the design complexity is simply the connectivity. When the connectivity varies, bottlenecks can arise in which a few components limit progress. In this case the design complexity depends on the details of the design. The number of bottlenecks also determines whether progress is steady, or whether there are periods of stasis punctuated by occasional large changes. Our model connects the engineering properties of a design to historical studies of technology improvement.Keywords
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This publication has 31 references indexed in Scilit:
- The Perils of the Learning Model for Modeling Endogenous Technological ChangeThe Energy Journal, 2014
- Schumpeterian economic dynamics as a quantifiable model of evolutionNew Journal of Physics, 2010
- Beyond the learning curve: factors influencing cost reductions in photovoltaicsEnergy Policy, 2006
- Technological innovation and complexity theoryEconomics of Innovation and New Technology, 2006
- Learning rates for energy technologiesEnergy Policy, 2001
- Learning Curves in ManufacturingScience, 1990
- Treating Progress Functions as a Managerial OpportunityAcademy of Management Review, 1984
- Debunking the Learning CurveIEEE Transactions on Components, Hybrids, and Manufacturing Technology, 1982
- Measurement of technology progress and capital cost for nuclear, coal-fired, and gas-fired power plants using the learning curveEngineering and Process Economics, 1979
- Studies on the telegraphic language: The acquisition of a hierarchy of habits.Psychological Review, 1899