A Negotiator's Backup Plan: Optimal Concessions with a Reservation Value
Tamara C. P. Florijn, Pinar Yolum, Tim Baarslag
TL;DR
The paper addresses optimal bidding under private reservation values in bilateral negotiations and introduces the Marginal Improvement Algorithm for Reservation Values (MIA-RVelous), a greedy method that inserts the reservation value and iteratively adds bids with maximal marginal improvement to maximize $EU_{rv}(\pi)$, achieving $O(n^2D)$ time. It proves the optimality of the resulting bid sequence and demonstrates how the reservation value can drive the selection of riskier, higher-utility bids. The discussion outlines extensions to probabilistic reservation values and to concurrent, multi-thread negotiations, underscoring practical impacts for backup-plan aware negotiation strategies.
Abstract
Automated negotiation is a well-known mechanism for autonomous agents to reach agreements. To realize beneficial agreements quickly, it is key to employ a good bidding strategy. When a negotiating agent has a good back-up plan, i.e., a high reservation value, failing to reach an agreement is not necessarily disadvantageous. Thus, the agent can adopt a risk-seeking strategy, aiming for outcomes with a higher utilities. Accordingly, this paper develops an optimal bidding strategy called MIA-RVelous for bilateral negotiations with private reservation values. The proposed greedy algorithm finds the optimal bid sequence given the agent's beliefs about the opponent in $O(n^2D)$ time, with $D$ the maximum number of rounds and $n$ the number of outcomes. The results obtained here can pave the way to realizing effective concurrent negotiations, given that concurrent negotiations can serve as a (probabilistic) backup plan.
