Table 3Ordered probit results, marginal probability estimates

Variable HMO PPO Indemnity
Constant 0.158 −0.048 −0.110
Hospital HERF −0.189** 0.057** 0.131**
Physicians per 10,000 capita 0.009** −0.003** −0.006**
Hospital assets per capita −0.019 0.006 0.014
Income per capita 0.002 −0.001 −0.001
Young people −0.004 * 0.001 0.003 *
Seniors 0.006 −0.002 −0.004
Population density 0.007 * −0.002 −0.005 *

HERF = hospital Herfindahl index; HMO = health maintenance organization; Indemnity = indemnity plan; Kaiser = Kaiser HMO; PPO = preferred provider organization.

**

Coefficient is statistically significant at the 95 percent level or better.

From: Where Do HMOs and PPOs Locate? Debunking an Urban Myth

Cover of Where Do HMOs and PPOs Locate? Debunking an Urban Myth
Where Do HMOs and PPOs Locate? Debunking an Urban Myth [Internet].
Grefer J, Mobley LR, Frech HE III.
Research Triangle Park (NC): RTI Press; 2009 Mar.
© 2009 Research Triangle Institute. All rights reserved.

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