  We study a portioning setting in which a public resource such as time or
money is to be divided among a given set of candidates, and each agent proposes
a division of the resource. We consider two families of aggregation rules for
this setting - those based on coordinate-wise aggregation and those that
optimize some notion of welfare - as well as the recently proposed Independent
Markets mechanism. We provide a detailed analysis of these rules from an
axiomatic perspective, both for classic axioms, such as strategyproofness and
Pareto optimality, and for novel axioms, which aim to capture proportionality
in this setting. Our results indicate that a simple rule that computes the
average of all proposals satisfies many of our axioms, including some that are
violated by more sophisticated rules.
