High-bidder always computed * based on the current hotel prices as opposed to using priors and averages of past closing prices Low-bidder always computed * as in variant * but also only bid for hotel rooms at over the current ask price as opposed to the marginal utility which tended to be e more than $
At the extremes with ATTac-200 and high-bidders playing at least one hotel price skyrockets in every game since all agents bid very high for the hotel rooms  On the other hand  with ATTac-200 and   low-bidders playing  hotel prices never skyrocket since all agents but ATTac-200 bid close to the ask price Our goal was to measure whether ATTac2000 could perform well in both extreme scenarios as well as various intermediate ones summarizes our results Table

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Table The difference between ATTac-2000s score and the score of each of the other seven agents averaged over all games in a controlled experiment All differences are statistically significant at the level except the one marked in italics Each row corresponds to a different number of high bidders excluding ATTac2000 itself The first column presents the number of high bidders as well as the nnmmmmeeerrrreeerrreeerrreeerrreeerrreeerrreeerrreeerrreeerrreeerrreeerrreeerrreeerrreeerrreeerrreeerrre The column labeled agent " shows how much better ATTac-2000 did on average than agent the Scores above the stair step line are for high bidders  variant and scores below ting the line are for low bidders  variant Results for identical agents are averaged to obtain a single average score difference for each type of agent in each row  In all cases  ATTac-2000 beats the other agents Each row of Table   corresponds to a different number of high bidders in the game for example the row labeled with high bidders corresponds to ATTac 2000 playing with Results for identical agents are averaged copies of variant and copies of variant to obtain a single average score difference for each type of agent in each row  In the first column  we also show in parentheses the number of games played for the results in each row each row reflects a different number of runs In all cases we ran enough game instances to achieve statistically significant results  However in some cases we ran more instances than turned out to be required  The column labeled agent   shows the difference between ATTac-200 s score and the score of agent averaged over all games In all scenarios these