A computer-implemented method for determining a bid for a auction. A valuation for the auction, a risk preference, and a rate of change of the risk preference are received. A joint distribution is determined based on historical auction information and at least one updated valuation for an historical auction. A density of the joint distribution is determined. The bid is determined based on the risk preference, the rate of change of the risk preference, the valuation, the joint distribution, and the density of the joint distribution.