Heterogeneity, Intrafamily Distribution and Child Health
利用哥伦比亚Candelaria地区1968-1974年的家庭数据，估计出生顺序、生育间隔、人均食物消费等因素对儿童出生时及出生后6个月内年龄标准化体重的影响，发现健康禀赋较好的家庭生育更多、间隔更短的孩子，但人均食物消费并未增加，表明家庭行为倾向于减少儿童健康的不平等。
Data were collected in Candelaria Colombia from 1968 to 1974 to evaluate the impact of child health services in all households in which there were any children under 6 years old. To estimate the birth outcome equation and post-birth health equation a subsample of 109 households was selected in which at least 2 children were born during the 7-year program. The sample size was 238 children. Estimates of the parameters of the normalized weight equations were obtained using seemingly-unrelated-regression (SUR) the family fixed effects procedure (FFE) and the lagged instrumental fixed effects technique (LIFE). An illustrative dynamic model of intra-family allocative behavior incorporating variations in individual child characteristics was formulated to show how both the timing of childbearing and child-specific allocations vary with both family and child-specific health endowments. The information restrictions were used in the model associated with the sequencing of births to develop an estimation procedure which takes into account both intrafamily and interfamily heterogeneity. Longitudinal data on children and households compared estimates of the effects of birth order birth spacing and timing per capita food consumption inoculations and the incidence of breast feeding on the age-standardized weight of children at 2 life-cycle points: at birth and within 6 months after birth. The estimates indicated that healthier families for given income had more children and more closely spaced children but consumed no more food per capita than did less well-endowed families. These results imply that families behave so as to reduce inherent interfamily inequalities in child health. However while the estimates suggest that the healthier the prior surviving child the more quickly parents are likely to have a subsequent child parents are also more likely to breastfeed an inherently healthier child.