We analyze the link between entry and R&D spending distribution. We consider a monopolistic competitive market with free entry in which firms can invest in cost-cutting R&D by paying a fixed cost first. For an intermediate level of fixed cost, there is a unique equilibrium in which the market...

We study a dynamic matching environment where individuals arrive sequentially. There is a trade‐off between waiting for a thicker market, allowing for higher‐quality matches, and minimizing agents' waiting costs. The optimal mechanism cumulates a stock of incongruent pairs up to a threshold...