@Override
 /** Bid the minimum amount possible. */
 public int bidAmount(Auction auction) {
   int amount = auction.minimumBid();
   if (r.nextDouble() > 0.98) {
     int change =
         Math.max(
             0, (int) ((1 - auction.proportionOfTrueValuation()) * 0.1 * auction.trueValue()));
     amount += change;
   }
   return amount;
 }