We report on an experiment examining why default options impact behavior. By randomly assigning employees to different varieties of a salary-linked savings account, we find that default enrollment increases participation by 40 percentage points--an effect equivalent to providing a 50% matching...

One-fifth of the world's population lives in countries affected by fragility, violence and conflict, impeding long-term economic growth. However, little is known about how firms respond to local changes in security, partly because of the difficulty of measuring firm activity in these settings....

Building state capacity is uniquely challenging in fragile states. We report results from a randomized evaluation of a major Afghan government initiative to increase capacity by modernizing its payroll. The reform, which required teachers to biometrically register and receive salary payments via...

Building state capacity is uniquely challenging in fragile states. We report results from a randomized evaluation of a major Afghan government initiative to increase capacity by modernizing its payroll. The reform, which required teachers to biometrically register and receive salary payments via...

Religious adherence has been hard to study in part because it is hard to measure. We develop a new measure of religious adherence, which is granular in both time and space, using anonymized mobile phone transaction records. After validating the measure with traditional data, we show how it can...