A DYNAMIC NONLINEAR OPTIMIZATION STUDY OF MOUNTAIN PIMA SUBSISTENCE TECHNOLOGY

A dynamic nonlinear optimization analysis of subsistence patterns of t he Mountain Pima of Chihuahua, Mexico, included requirements for adequ ate amounts of calories, calcium, vitamin A, vitamin C, and balanced p rotein. Two methods of incorporating nonenergy nutritional needs into a time minimization program were compared. The first was a constraint model with sharp boundaries between adequacy and fatality. The second involved multiplying the total work time by a series of nutrient index ing factors. Each factor was calculated as a function of the ratio bet ween the recommended and actual rates of intake for all months and nut rients considered. Oxalate composition of some resources and seasonal variation in resource availability were taken into account. Two sets o f data were analyzed, one for a year of adequate rainfall, the other f or a year of severe drought. The predictions of the indexing model agr eed more closely with observed intake patterns than did the prediction s of the constraint model.