2005/23 | LEM Working Paper Series | |
How to Construct Alternatives. A computational voting model |
||
Luigi Marengo, Corrado Pasquali |
||
Abstract | ||
Social choice models usually assume that choice is among pre-defined, uni-dimensional and "simple" objects.
Very often, on the contrary, choice is among multi-featured and "complex" objects: a candidate in an election
stands for an electoral programme which is a complex bundle of many interdependent political positions
on a wide variety of issues. Also in committees and organizations of various sorts
collective choices are most often made among policy "bundles" and authorities
can act upon the pre-choice stage of construction of such bundles. This pre-choice
power of alternatives construction may grant authorities a highly effective device
to influence the outcome of social choice even when the latter is totally free and
democratic.
In this paper we propose a model which investigates within a simple majority
vote framework the role of the object construction power, an analogous to the
agenda power. Even when object construction is simply defined as the possibility
of assembling and dis-assembling a fixed set of choice components into bundles, we
show that, under rather general conditions, it can radically change the outcome of
the majority voting process. In particular we show that any set of bundles (that
we call "choice modules") is associated to a set of possible social outcomes which
can be attained depending upon the initial conditions. Moreover we shows that
also Condorcet-Arrow cycles can appear or disappear depending upon which set
of modules is chosen.
|
||
Downloads | ||
|
||
Back |