“…One, followed, for instance, by Williams (1993) for the real estate market, is to assume that ex-ante there are n symmetric firms, 1,..., n , whose value depends on exogenous state variables and in equilibrium all firms invest at the same time as soon as a given threshold is reached. Another, followed by Bouis et al (2009), is to assume that ex-ante there are more than two firms (three in this case) whose value depends on exogenous state variables but firms enter the market sequentially, providing analytical (or quasi-analytical) solutions for the investment thresholds of each firm. This latter approach seems more realistic, particularly for large oligopolies where the coordination for simultaneous investment is hardly feasible, but analytically very challenging as the number of firms grows.…”