Investment in Oligopoly under Uncertainty : The Accordion Effect

In the strategic investment under uncertainty literature the trade off between the value of waiting known from single decision maker models and the incentive to preempt competitors is mainly studied in duopoly models.This paper aims at studying competitive investments in new markets where more than two (potential) competitors are present.In case of three firms an accordion effect in terms of investment thresholds is detected in the sense that an exogenous demand shock results in a change of the wedge between the investment thresholds of the first and second investors that is qualitatively different from the change of the wedge between the second and third investment threshold.This result extends to the n firm case.We show that a direct implication of the accordion effect is that there are two types of equilibria in the three firm case.In the first type all firms invest sequentially and in the second type the first two investors invest simultaneously and the third investor invests at a later moment.If we consider sequential equilibria and compare entry times of the first investors for different potential market sizes, it turns out that in the two firm case the first investor invests earlier than in the monopoly case, in the three firm case the investment timing lies in between the one and the two firm case, the four firm case lies in between the two and the three firm case, and so on and so forth.Hence, a policy maker interested in an early start up should hope for an even number of competitors, although for n large the investment times of the first investors are almost equal.