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My name is pronounced: Day-vee Wex

Welcome! I am a fifth-year Ph.D. student in the Department of Economics at the Massachusetts Institute of Technology (MIT). My research is in development economics and organizational economics, focusing on technology and firms in lower-income countries, particularly in West Africa.

My dissertation explores how digital technologies reshape economic relationships and contract structures within and between firms, while uncovering the key drivers and barriers to their adoption.

Over the past eight years, I have conducted research projects in Côte d'Ivoire, Ethiopia, Senegal, and Togo.

I will be on the Academic Job Market in Fall 2024. [CV] - houeix@mit.edu

Working Papers

  1. Digitalization and Within-Firm Contracts (Job Market Paper), Draft Coming Soon
    Abstract

    I combine two field experiments in Senegal with a contract theory model to examine the impact of digital payment technologies on within-firm contracts. These technologies make transactions observable to employers, reducing moral hazard, but potentially hindering initial adoption by employees due to their informational rent. In the first experiment, I randomized access to digital payment technology for taxi drivers and within this group, further randomized the degree to which transactions are observable by employers in a panel of 613 owner-driver relationships. I find that digital payments benefit drivers and serve as effective monitoring tools for taxi owners. Enhanced transaction observability increases worker effort, shifts contracts toward fixed wages, and reduces turnover. However, the introduction of the technology leads to a separating equilibrium among workers: 50% of drivers, primarily the least productive and poorest, refused to adopt it, thus exacerbating welfare inequality. The second experiment reveals that assuring these drivers that digital transactions would remain undisclosed to owners nearly doubles adoption rates. Structural simulations suggest that a complete shift to wage employment, where owners are fully informed about worker types and actions, combined with subsidies for technology adoption, would substantially increase welfare. These findings highlight the trade-off between transparency and adoption of digital technologies, stressing the need for policymakers and innovators to consider distributional impacts to ensure broad adoption and enhance firm growth.

  2. Nationwide Diffusion of Technology Within Firms’ Social Networks, Draft Coming Soon
    Abstract

    I conduct a randomized experiment to study nationwide technology diffusion of a new digital payments technology in Senegal. By leveraging two novel sources of network data - mobile money transactions and anonymized phone contact directories covering the near universe of the adult population in Senegal - I identify three sets of spillovers from taxi firms randomized to receive early access to the technology: to other firms within the taxi industry; to other industries; and to other cities. I show that spillovers go beyond strategic complementarities, reflecting social learning facilitated by social ties and remote interactions.

  3. Relational Frictions Along the Supply Chain: Evidence from Senegalese Traders (with Edward Wiles), Draft Coming Soon

  4. Financial Inclusion and Rural Electrification: Evidence from Togo (with Paul Brimble, Axel Eizmendi Larrinaga, and Toni Oki), Draft Coming Soon
    Abstract

    Despite recent advancements, most people in sub-Saharan Africa still lack electricity. While rural electrification has garnered policy attention, recent academic literature estimates low demand. We argue that high transaction and transport costs for paying electricity bills - a critical friction faced by rural households - partly explain this puzzle and weaken policy effectiveness. We examine the scattered rollout of two nationwide policies in Togo in 2019 to support this claim: a subsidy program for solar home systems and an expansion of mobile money agents. The subsidy, which nearly halved the price, doubled adoption rates, primarily among customers near mobile money agents. These customers could reduce their payment frequency and buy in bulk, due to lower baseline transaction costs. The follow-up mobile money agent expansion reduced transaction costs directly, leading to a decrease in payment frequency due to a large income effect. In this setting of high liquidity constraints, the ability to buy in bulk outweighed the benefits of cheaper consumption smoothing. Our findings highlight the complementary role of subsidies and financial inclusion in increasing access to essential services.

  5. Eliciting Poverty Rankings from Urban or Rural Neighbors: Methodology and Empirical Evidence (with Pascaline Dupas and Marcel Fafchamps), Revised August 2024 for Quantitative Economics
    Abstract | PDF

    We introduce a novel approach for eliciting relative poverty rankings that aggregates partial orderings reported independently by multiple neighbors. We first identify the conditions under which the method recovers more accurate rankings than the commonly used Borda count method. We then apply the method to secondary data from rural Indonesia and to original data from urban Cote d’Ivoire. We find that the aggregation method works as well as Borda count in the rural setting but, in the urban setting, reconstructed rankings from both the pairwise and Borda count methods are often incomplete and sometimes contain ties. This disparity suggests that eliciting poverty rankings by aggregating rankings from neighbors may be more difficult in urban settings. We also confirm earlier research showing that poverty rankings elicited from neighbors are correlated with measures of poverty obtained from survey data, albeit not strongly. Our original methodology can be applied to many situations in which individuals with incomplete information can only produce a partial ranking of alternatives.

Selected Work in Progress

  • Digitalization of Local Tax Collection in Côte d’Ivoire (with Pascaline Dupas)

Other Publications