Strategic Bidding in Knapsack Auctions
Peyman Khezr, Vijay Mohan, Lionel Page
TL;DR
This work examines knapsack auctions where object values are private and sizes are public, embedded within a Greedy allocation framework. It analyzes three payment rules—Uniform-Price, Discriminatory Price, and Generalized Second Price—through theory, lab experiments with human bidders, and AI-driven simulations. The UP mechanism is shown to be DSIC and unique but inefficient, while DP and GSP yield higher revenue, with GSP closely matching UP in efficiency in practice. Across all methods, results indicate clear trade-offs between truthfulness, revenue, and efficiency, providing practical guidance for market design in NP-hard allocation problems under incomplete information, with AI simulations offering scalability and robustness checks.
Abstract
This paper examines knapsack auctions as a method to solve the knapsack problem with incomplete information, where object values are private and sizes are public. We analyze three auction types-uniform price (UP), discriminatory price (DP), and generalized second price (GSP)-to determine efficient resource allocation in these settings. Using a Greedy algorithm for allocating objects, we analyze bidding behavior, revenue and efficiency of these three auctions using theory, lab experiments, and AI-enriched simulations. Our results suggest that the uniform-price auction has the highest level of truthful bidding and efficiency while the discriminatory price and the generalized second-price auctions are superior in terms of revenue generation. This study not only deepens the understanding of auction-based approaches to NP-hard problems but also provides practical insights for market design.
