Simplifying Automated Hoarding Methods

A number of mobile computing systems have used the technique of hoarding, which allows a mobile device to store a chosen subset of known files, to give disconnected users the illusion of a complete filesystem in the presence of limited storage. We undertook an extensive and detailed simulation study of the parameters of a well-known hoarding system, Seer, in an attempt to discover the parameters that would produce the best performance. To our surprise, we discovered that the best parameter combinations were those that completely disabled Seer's complex clustering methods, reverting the system instead to a modified form of LRU hoarding. We discuss the experiments and our results, and propose designs for future systems and directions for future research

Factors associated with cognitive achievement in late childhood and adolescence: The Young Lives cohort study of children in Ethiopia, India, Peru, and Vietnam

Background: There is a well-established link between various measures of socioeconomic status and the schooling achievement and cognition of children. However, less is known about how cognitive development is impacted by childhood improvements in growth, a common indicator of child nutritional status. This study examines the relationship between socioeconomic status and child growth and changes in cognitive achievement scores in adolescents from resource-poor settings. Methods: Using an observational cohort of more than 3000 children from four low- and middle-income countries, this study examines the association between cognitive achievement scores and household economic, educational, and nutritional resources to give a more accurate assessment of the influence of families on cognitive development. A composite measure of cognition when children were approximately 8, 12, and 15 years of age was constructed. Household factors included maternal schooling, wealth, and children’s growth. Results: A positive and statistically significant relationship between household factors and child cognition was found for each country. If parents have more schooling, household wealth increases, or child growth improves, then children’s cognitive scores improve over time. Results for control variables are less consistent. Conclusion: Our findings suggest there is a consistent and strong association between parental schooling, wealth, and child growth with child cognitive achievement. Further, these findings demonstrate that a household’s ability to provide adequate nutrition is as important as economic and education resources even into late childhood and adolescence. Hence, efforts to improve household resources, both early in a child’s life and into adolescence, and to continue to promote child growth beyond the first few years of life have the potential to help children over the life course by improving cognition.This study is supported by the Bill and Melinda Gates Foundation (Global Health Grant OPP10327313), Eunice Shriver Kennedy National Institute of Child Health and Development (Grant R01 HD070993), and Grand Challenges Canada (Grant 0072-03 to the Grantee, The Trustees of the University of Pennsylvania). The data used in this study come from Young Lives, an international study of childhood poverty, following the lives of 12,000 children in four countries – Ethiopia, India, Peru and Vietnam – over 15 years (www.younglives.org.uk). Young Lives is core-funded by UK aid from the Department for International Development (DFID) and co-funded from 2010-2014 by the Netherlands Ministry of Foreign Affairs, and by Irish Aid from 2014 to 2015. Findings and conclusions in this article are those of the authors and do not necessarily reflect positions or policies of the Bill and Melinda Gates Foundation, the Eunice Kennedy Shriver National Institute of Child Health and Human Development, Grand Challenges Canada, Young Lives, DFID or other funders