banerjee and his co-workers try to measure the effectiveness of actions (such as government programmes) in improving people's lives. for this, they use randomized controlled trials, similar to clinical trials in medical research. for example, although polio vaccination is freely available in india, many mothers were not bringing their children for the vaccination drives. banerjee and prof. esther duflo, also from mit, tried an experiment in rajasthan, where they gifted a bag of pulses to mothers who vaccinated their children. soon, the immunization rate went up in the region. in another experiment, they found that learning outcomes improved in schools that were provided with teaching assistants to help students with special needs.