This paper empirically investigates the effect of the competitive environment (number of participants) on the cost of procurement. We use a unique dataset provided by the Public Procurement Authority (PPA) of Turkey that covers all of the government procurement auctions for the years...

Using online auction data, we address the endogeneity involved in estimating the eff ect of the number of bidders on the winning bid. We introduce a novel instrumental variable. Our results indicate that the bias arising from treating the number of bidders as exogenous, is substantial