Incentive to Reduce Cost under Incomplete Information

I examine how ex ante symmetric firms that compete in prices strategically decide to invest in research and development of cost-reducing technology when the rival firm and the consumers are not aware of the actual outcome of the investment. I also compare the strategic incentive to invest and market outcomes under incomplete information with that of the full information. I find that equilibrium investment under incomplete information with unobservable investment is same as that of (symmetric) full information equilibrium and is also socially optimal.