Skip to main content
Fig. 5 | BMC Medical Research Methodology

Fig. 5

From: Heckman-type selection models to obtain unbiased estimates with missing measures outcome: theoretical considerations and an application to missing birth weight data

Fig. 5

Inverse Mills ratio for wealth quintile by IFAS. Shows the expected probability of selection by wealth quintile and supplementation. The average difference in the selection probabilities (likelihood of having BW data) is about 25 percentage points across all wealth quintiles, suggesting that a potentially rather different pool of women is observed in the treatment and control groups. This difference is reflected in the inverse mills ratio (IMR) correction term the Heckman model estimates in Appendix Fig. 4. The average difference in the IMR between women with IFAS and women without IFAS is 0.30 standard deviations in the unobserved latent selection trait ν

Back to article page

BMC Medical Research Methodology

ISSN: 1471-2288

Contact us