Citation:
Econometrica, 1996, v. 64, n. 3, p. 691-704
ISSN:
1468-0262
Sponsor:
The authors are grateful for financial support from NSF Grants SBR-9223320, SBR-9223175,
SBR-9409180, DGICYT PB92-0245, Human Capital Mobility Programme ERBCHBICT940975, and
the VCLA Academic Senate