A few years ago, economist Esther Duflo, PhD ‘99, found a problem that threatened to stump her. In the rural villages of Udaipur, a district in northern India with one of the worst child mortality rates in the world, parents were spurning health clinics’ offer of free immunizations against deadly diseases such as measles and tuberculosis. Only 2 percent of local children were being immunized by age two.
Duflo, MIT’s Abdul Latif Jameel Professor of Poverty Alleviation and Development Economics, specializes in finding unorthodox ways to help the world’s poor. So she concocted an experiment with MIT-based collaborators Abhijit Banerjee and Rachel Glennerster, along with officials from Seva Mandir, a local nongovernmental organization. In some villages, they offered parents about two pounds of free lentils when they brought their children in for shots. Before long, families started streaming into these clinics. About four in 10 children got immunized where free lentils were available.
According to mainstream economic thinking, the success of the lentil giveaway made no sense. The shots were already free. The lentils, a cheap staple of the Indian diet, added little value. “The standard theory of human capital accumulation cannot explain why you go from a few percent to 38 percent,” says Duflo. “The fact that there is huge responsiveness to such a small thing is contrary to theory.”