# Multi-unit Assignment under Dichotomous Preferences

## TL;DR

This paper investigates a money-free allocation problem where agents with accept/reject preferences are assigned multiple objects, showing that the egalitarian solution has advantageous fairness and strategic properties over the competitive equilibrium.

## Contribution

It introduces the egalitarian solution for multi-unit assignment with dichotomous preferences, highlighting its fairness, uniqueness, and strategy-proofness, and compares it to the competitive equilibrium.

## Key findings

- Egalitarian solution is Lorenz dominant and utility unique.
- Egalitarian solution is group strategy-proof.
- Both solutions are disjoint in this setting.

## Abstract

I study the problem of allocating objects among agents without using money. Agents can receive several objects and have dichotomous preferences, meaning that they either consider objects to be acceptable or not. In this setup, the egalitarian solution is more appealing than the competitive equilibrium with equal incomes because it is Lorenz dominant, unique in utilities, and group strategy-proof. Moreover, it can be adapted to satisfy a new fairness axiom that arises naturally in this context. Both solutions are disjoint.