We model charter school entry and choice of educational practices. Student achievement depends on cognitive ability, motivation, effort, and match of school curriculum to ability. Exercising charter school autonomy over curriculum, to maximize achievement gains, the charter sets curriculum to...

Quantifying factors giving rise to temporal variation in forest fires is important for advancing scientific understanding and improving fire prevention. We demonstrate that eighty percent of the large year-to-year variation in forest area burned in California can be accounted for by variation in...