Customer Preference Discontinuities: A Trigger for Radical Technological Change. Managerial and Decision Economics, forthcoming

Abstract The technology life cycle literature provides strong theoretical foundations that explain how an era of technological ferment culminates in a dominant design, as well as how technology progresses during the resulting era of incremental change. But the processes by which subsequent technological discontinuities occur, particularly their timing, remains relatively unexplored. What factors cause an industry to move from maturity back to a period of turbulence? This paper develops a model of technological evolution that incorporates both technological trajectories and a new concept: preference trajectories, which are cycles of incremental and discontinuous change in preferences. Preference discontinuities turn out to play an important role in triggering technological transitions in an industry. The model is illustrated using an in-depth historical study of 100 years in the typesetter industry, which underwent three major technological transitions, each of which was driven by preference discontinuities.

A reaction landscape identifies the intermediates critical for self-assembly of virus capsids and other polyhedral structures

The capsids of spherical viruses may contain from tens to hundreds of copies of the capsid protein(s). Despite their complexity, these particles assemble rapidly and with high fidelity. Subunit and capsid represent unique end states. However, the number of intermediate states in these reactions can be enormous—a situation analogous to the protein folding problem. Approaches to accurately model capsid assembly are still in their infancy. In this paper, we describe a sailshaped reaction landscape, defined by the number of subunits in each species, the predicted prevalence of each species, and species stability. Prevalence can be calculated from the probability of synthesis of a given intermediate and correlates well with the appearance of intermediates in kinetics simulations. In these landscapes, we find that only those intermediates along the leading edge make a significant contribution to assembly. Although the total number of intermediates grows exponentially with capsid size, the number of leading-edge intermediates grows at a much slower rate. This result suggests that only a minute fraction of intermediates needs to be considered when describing capsid assembly