Please use this form to submit your study for inclusion into our database. It will be checked by a member of the Innovation Growth Lab team, who may be in contact to ask for more information. Your email address * Your name * Title * The name of the study Short summary A randomized control trial in central Tanzania, centered on the production and distribution of a ”Yellow Pages” phone directory with contact information for local enterprises. A brief description of the project's goals and its current state Abstract <p>Mobile phones reduce the cost of communicating with existing social contacts, but do not eliminate frictions in forming new relationships. We report the findings of a two-sided randomized control trial in central Tanzania, centered on the production and distribution of a ”Yellow Pages” phone directory with contact information for local enterprises. Enterprises randomly assigned to be listed in the directory receive more business calls, make greater use of mobile money, and are more likely to employ workers. There is evidence of positive spillovers, as both listed and unlisted enterprises in treatment villages experience significant increases in sales relative to a pure control group. Households randomly assigned to receive copies of the directory make greater use their phones for farming, are more likely to rent land and hire labor, have lower rates of crop failure, and sell crops for weakly higher prices. Willingness-to-pay to be listed in future directories is significantly higher for treated enterprises.</p> The full abstract of the study, if available Links http://www.jblumenstock.com/files/papers/DAB-yellow_pages.pdf Links to any published papers and related discussions Authors * Affiliations Academic and other institutes that the authors of the study are members of Delivery partner Organisations involved in delivering the trial, if appropriate Year Year Year199419951996199719981999200020012002200320042005200620072008200920102011201220132014201520162017201820192020202120222023202420252026 Month MonthJanFebMarAprMayJunJulAugSepOctNovDec Day Day12345678910111213141516171819202122232425262728293031 Journal Journal publishing the study, if available Publication stage * Working Paper Published Ongoing Research Forthcoming Discussion Paper Research theme * Entrepreneurship Innovation Business Growth Country Country or countries where this study took place. Topics What sort of topics does the study cover? Sample attributes Hypotheses / research question Sample Trial population and sample selection Number of treatment groups Size of treatment groups Size of control group Unit of analysis Clustered? Yes No Cluster details Trial attributes Treatment description Rounds of data collection Baseline data collection and method Data collection method and data collected Evaluation Outcome variables Results Intervention costs Cost benefit ratio Reference Citation for use in academic references