Can mechanism design save democracy? We propose a simple design that offers a chance: individuals pay for as many votes as they wish using a number of "voice credits" quadratic in the votes they buy. Only quadratic cost induces marginal costs linear in votes purchased and thus welfare optimality...

We consider the problem of allocating a single object to the agents with payments. Agents have preferences that are not necessarily quasi-linear. We characterize the class of rules satisfying pairwise strategy-proofness and non-imposition by the priority rule. Our characterization result remains...

This online appendix proves the central result in Lalley and Weyl (Forthcoming). The full text PDF for "Qaudratic Voting: How Mechanism Design Can Radicalize Democracy" may be found here: http://ssrn.com/abstract=2003531

Consider a setting in which individual strict preferences need to be aggregated into a social strict preference relation. For two alternatives and an odd number of agents, it follows from May’s Theorem that the majority aggregation rule is the only one satisfying anonymity, neutrality, and...

We consider the allocation problem of assigning heterogenous objects to a group of agents and determining how much they should pay. Each agent receives at most one object. Agents have non-quasi-linear preferences over bundles, each consisting of an object and a payment. Especially, we focus on...

Condorcet domains are sets of linear orders with the property that, whenever the preferences of all voters of a society belong to this set, their majority relation has no cycles. We observe that, without loss of generality, every such domain can be assumed to be closed in the sense that it...

This paper analyzes how to choose a delegation, a committee to represent a society such as in a peace conference. We propose normative conditions and seek optimal, consistent, neutral, and non-manipulable ways to choose a delegation. We show that a class of threshold rules are characterized by...

This paper analyzes strategy-proof collective choice rules when individuals have single-crossing preferences on a finite and ordered set of social alternatives. It shows that a social choice rule is anonymous, unanimous, and strategy-proof on a maximal single-crossing domain if and only if it is...

Let 𝝫𝑛 be the set of the binary strategy-proof social choice functions referred to a group of n voters who are allowed to declare indifference between the alternatives. We provide a recursive way to obtain the set 𝝫𝑛+1 from the set 𝝫𝑛. Computing the cardinalities |𝝫𝑛|...

We study strategy-proof rules for choosing between two alternatives. We consider the full preference domain which allows for indifference. In this framework, for strategy proof rules, ontoness does not imply efficiency. We weaken the requirement of efficiency to ontoness and characterizes the...