Center for Effective Global Action

We provide evidence that mobile phone records can be used to predict the socioeconomic status and other welfare indicators of individual mobile phone subscribers. Combing several terabytes of anonymized transactional mobile phone records with data collected through 2,200 phone-based interviews, we test the extent to which it is possible to predict an individual's responses to survey questions based on phone records alone. We observe signicant correlations between asset ownership and a rich set of measures derived from the phone data that capture phone use, social network structure,and mobility.

Simple classication methods are able to predict, with varying degrees of accuracy, whether the respondent owns assets such as radios and televisions, as well as xed house- hold characteristics such as access to plumbing and elec- tricity. More modest results are obtained when attempting to predict a broader set of development indicators such as an individual's response to the question, "Have you had to pay unexpected medical bills in the past 12 months?" While these methods oer a powerful opportunity for policymakers and researchers working in developing countries, we argue that considerable calibration and renement is needed before such methods can be deployed.