Microlending, where a bank lends to a small group of people without credit histories, began with the Grameen Bank in Bangladesh, and is widely seen as the creation of Muhammad Yunus, who received the Nobel Peace Prize in recognition of his largely successful efforts. Since that time the modeling of microlending has received a fair amount of academic attention. One of the issues not yet addressed in full detail, however, is the issue of the size of the group. Some attention has nevertheless been paid using an experimental and game theory approach. We, instead, take a mathematical approach to the issue of an optimal group size, where the goal is to minimize the probability of default of the group. To do this, one has to create a model with interacting forces, and to make precise the hypotheses of the model. We show that the original choice of Muhammad Yunus, of a group size of five people, is, under the right, and, we believe, reasonable hypotheses, either close to optimal, or even at times exactly optimal, i.e., the optimal group size is indeed five people.
相似文献The study of the nutritional status is relevant during the entire life course, but in children it is relevant as malnutrition may be a marker of underlying functional and mental health deficits. Evidence of the association between malnutrition and school dropout is not conclusive. Our aim was to analyze children’s nutritional trajectory measured using their Body Mass Index (BMI) of a Uruguayan cohort and its association with school dropout. With this purpose, Latent Class and Joint Latent Class Mixed Models were fitted to children’s cohort study (N?=?1392 girls and 1492 boys) in sex-stratified analyses adjusting for sociodemographic characteristics. We identified latent classes of boys and girls with similar BMI trajectories during school years and differences in relevant socioeconomic and anthropometric characteristics. Results indicated that boys dropped out at younger ages than girls. No association between age of school dropout and nutritional trajectory classes was found. None of the classes exhibited a deficit or decrease in BMI trajectories during school ages, although the obesity and overweight classes could be of concern. Results suggested no significant association between obesity or overweight and age of school dropout for children up to 14 years old. Future research on other samples may inform about trajectories in higher educational levels.
相似文献