9 citations · 32 across the 17 of their papers we have counts for
17 papers
Fair Allocation with Optional Selling
Uriel Feige, Yotam Gafni
We consider fair allocation of indivisible goods in a setting in which agents have subjective valuation functions over the set of goods, and in addition, goods may be sold at given…
Centralization and Stability in Formal Constitutions
Yotam Gafni
Consider a setting where a social choice function (SCF) is chosen to decide votes in a formal system, including votes to replace the voting method itself. Voters vote according to…
A Small Collusion is All You Need
Yotam Gafni
Transaction Fee Mechanisms (TFMs) study auction design in the Blockchain context, and emphasize robustness against miner and user collusion, moreso than traditional auction theory.…
Envious Explore and Exploit
Omer Ben-Porat, Yotam Gafni, Or Markovetzki
Explore-and-exploit tradeoffs play a key role in recommendation systems (RSs), aiming at serving users better by learning from previous interactions. Despite their commercial succe…
Incentive-Compatible Collusion-Resistance via Posted Prices
Matheus V. X. Ferreira, Yotam Gafni, Max Resnick
We consider a refinement to the notions of collusion-resistance in transaction fee mechanisms. In particular, we require that the collusion is by itself incentive-compatible and in…
Beyond Proportional Individual Guarantees for Binary Perpetual Voting
Yotam Gafni, Ben Golan
Perpetual voting studies fair collective decision-making in settings where many decisions are to be made, and is a natural framework for settings such as parliaments and the runnin…
Prediction-sharing During Training and Inference
Yotam Gafni, Ronen Gradwohl, Moshe Tennenholtz
Two firms are engaged in a competitive prediction task. Each firm has two sources of data -- labeled historical data and unlabeled inference-time data -- and uses the former to der…
Barriers to Collusion-resistant Transaction Fee Mechanisms
Yotam Gafni, Aviv Yaish
To allocate transactions to blocks, cryptocurrencies use an auction-like transaction fee mechanism (TFM). A conjecture of Roughgarden [44] asks whether there is a TFM that is incen…
Scheduling With Time Discounts
Yotam Gafni, Aviv Yaish
We study a \emph{financial} version of the online problem of scheduling weighted packets with deadlines. The main novelty is that, while prior works assume packets have \emph{fixed…
Optimal Mechanism Design for Agents with DSL Strategies: The Case of Sybil Attacks in Combinatorial Auctions
Yotam Gafni, Moshe Tennenholtz
In robust decision making under uncertainty, a natural choice is to go with safety (aka security) level strategies. However, in many important cases, most notably auctions, there i…
Discrete & Bayesian Transaction Fee Mechanisms
Yotam Gafni, Aviv Yaish
Cryptocurrencies employ auction-esque transaction fee mechanisms (TFMs) to allocate transactions to blocks, and to determine how much fees miners can collect from transactions. Sev…
Long-term Data Sharing under Exclusivity Attacks
Yotam Gafni, Moshe Tennenholtz
The quality of learning generally improves with the scale and diversity of data. Companies and institutions can therefore benefit from building models over shared data. Many cloud…
A 2-Dimensional Binary Search for Integer Pareto Frontiers
Yotam Gafni
For finite integer squares, we consider the problem of learning a classification that respects Pareto domination. The setup is natural in dynamic programming settings. We show…
Unified Fair Allocation of Goods and Chores via Copies
Yotam Gafni, Xin Huang, Ron Lavi +1
We consider fair allocation of indivisible items in a model with goods, chores, and copies, as a unified framework for studying: (1)~the existence of EFX and other solution concept…
Worst-case Bounds on Power vs. Proportion in Weighted Voting Games with Application to False-name Manipulation
Yotam Gafni, Ron Lavi, Moshe Tennenholtz
Weighted voting games apply to a wide variety of multi-agent settings. They enable the formalization of power indices which quantify the coalitional power of players. We take a nov…
From Monopoly to Competition: Optimal Contests Prevail
Xiaotie Deng, Yotam Gafni, Ron Lavi +2
We study competition among contests in a general model that allows for an arbitrary and heterogeneous space of contest design, where the goal of the contest designers is to maximiz…
VCG Under False-name Attacks: a Bayesian Analysis
Yotam Gafni, Ron Lavi, Moshe Tennenholtz
VCG is a classical combinatorial auction that maximizes social welfare. However, while the standard single-item Vickrey auction is false-name-proof, a major failure of multi-item V…