What causes a group of countries to agree to form a federation? Other
alternative arrangements, which often an chosen instead, are to form a
unitary state or to remain autonomous. Federations usually allow for
considerable freedom of movement among constituent regions. They also
provide a fairly limited redistribution of any rents earned in these r
egions. These two features together imply that residents of poor regio
ns can share in the rents in rich regions by migration. This fiscal mi
gration may waste resources. Why not simply share the tents equally am
ong residents of all regions? Such a unitary arrangement, although eff
icient, would not appeal to residents of a country which is likely to
be the best-off region in a federation. Complete autonomy may expose r
esidents of the separate countries to considerable idiosyncratic risk.
Hen I demonstrate that federation may be chosen by a group of countri
es, even though it is a more wasteful arrangement than either other al
ternative, if asymmetries among countries, and the degree of risk aver
sion, are large. Federal states also often implement transfers among t
he regions. These transfers can be viewed as substitutes for fiscal mi
gration. I also show that the possibility of transfers, even without a
ny commitment to specifics, makes federalism a more attractive option.
A federal constitution which requires transfers in excess of what wou
ld be made voluntarily may make federalism more attractive still. (C)
1998 Elsevier Science S.A.