What is the cost of low participation in French timber auctions?

How much is the standing timber from public forests worth? To estimate the value of a timber lot, we adopt the transaction evidence appraisal approach using data from timber auctions in Lorraine (Eastern France) accounting for the facts that: (i) the seller's reserve prices are secret, (ii) there remain many unsold lots and (iii) the number of bidders varies across auctions. Taking into account the endogenous participation in our hedonic price equation for the highest bid, we estimate that, compared to lots that receive two bids, the highest bid is 22% lower when there is only one bid and 37% higher when there are three or more bids.