@article {653156,
	title = {Enrollee Mix, Treatment Intensity, and Cost in Competing Indemnity and HMO Plans},
	journal = {Journal of Health Economics},
	volume = {22},
	number = {1},
	year = {2003},
	pages = {23-45},
	author = {Daniel Altman and David Cutler and Richard Zeckhauser}
}
