“…The bidder now needs to estimate the distribution of the price to beat -the highest bid of the competition -to compute its optimal bid [Krishna, 2009]. Second, it is common for the bidder to have some constraints on the advertising campaign, such as a maximum budget per day, or a maximum cost per click [Conitzer et al, 2018, Heymann, 2019. While in several cases a linear scaling applied to the display valuation may be enough to optimally satisfy a budget constraint, the value of this scaling factor is not known in advance, and several articles propose to update the bidding strategy to better take such constraint into account [Cai et al, 2017, Grislain et al, 2019, Lee et al, 2013, Yang et al, 2019.…”