market share and advertising is the only strategic variable. Entry occurs when the relative effectiveness of incumbent …We analyze the relationship between market size and entry when an incumbent and a potential entrant compete to gain …'s advertising is smaller than a threshold level that depends on the size of the market. This threshold level is monotonically and …

that entry and exit rates are positively correlated across industries. Our objective is to investigate the effect of sunk … costs and, in particular, market size on entry and exit rates. We analyse a stochastic dynamic model of a monopolistically … show existence and uniqueness of a stationary equilibrium with simultaneous entry and exit: efficient firms survive while …

that entry and exit rates are positively correlated across industries. Our objective is to investigate the effect of sunk … costs and, in particular, market size on entry and exit rates, and hence on the age distribution of firms. We analyze a …. We show existence and uniqueness of a stationary equilibrium with simultaneous entry and exit: efficient firms survive …

and fixed costs may have interesting, non-obvious effects on entry and exit. Before costs change, the model exhibits … amounts of entry and exit. When costs rise, price rises and the market quantity supplied falls, but the amount of entry and … exit may rise or fall. The most intuitive outcome from a cost increase is the competitor neutral case, in which entry …

consumers we establish see-saws between consumers and advertisers. Entry of a lower-quality platform increases consumer surplus …, but decreases advertiser surplus if industry platform profits decrease with entry. Merger decreases consumer surplus, but … platforms use two-sided pricing or consumers like advertising,advertiser and consumer interests are often aligned. …

Schmalensee (1974) shows that, when the cost functions of the advertising e¤ort are linear, the monopoly position is … only sustained when the advertising�s e¤ectiveness of the incumbent is relatively high. We show that this result does not … hold in a more general nonlinear cost. The no-entry equilibrium may hold even when the relative e¤ectiveness of the …

consumers we establish see-saws between consumers and advertisers. Entry of a lower-quality platform increases consumer surplus …, but decreases advertiser surplus if industry platform profits decrease with entry. Merger decreases consumer surplus, but … platforms use two-sided pricing or consumers like advertising,advertiser and consumer interests are often aligned. …