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Explore the effectiveness of microcredit access through experimentation and innovation. Learn about the ongoing work, methodology, and impact measurement strategies to assess the broader definition of financial access. Discover implementation details and initial results in diverse market settings. Gain insights into the implications for lenders and potential benefits for households.
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Does Microfinance Make $ense?Experimental Approaches IFC M&E Conference May 9, 2006 Jonathan Zinman Dartmouth College
Plan for Talk • Evaluating Impacts of Microcredit Access Using Randomized Credit Supply Decisions • Design • Implementations • Some Results • Beyond Risk Assessment: Evaluating “Access” Interventions Broadly Defined • Other efficiency and strategy interventions • Enforcement • Pricing • Other contract terms: (maturity, loan size) • Savings takeup • Product presentation (marketing, mental accounting) • Product development (reminders) • Distribution Channels (“impulse savings”) • Beyond Impact Evaluation: Experimentation and Innovation • The importance of measuring why interventions (don’t) work • The possibility of transforming organizations into learning laboratories
Evaluating Impacts of Microcredit Access Using Randomized Credit Supply Decisions Ongoing work with Dean Karlan (Yale) Our Methodology: • Lender randomizes credit supply decisions: • Randomized-control design: social science gold standard • Subject pool of marginal applicants (“grey area”) • Some in grey area randomly treated (“derationed”) • Remaining in grey area control group (“rationed”) • We follow-up with household and/or business surveys: • Measure investments, broadly defined • Measure impacts, broadly defined • On borrowing/credit access • On various measures of well-being
Measuring ImpactsUsing Derationing • Impact= the difference in an outcome of interestin derationed and rationed groups: • Examples of outcomes: • lender’s profits • applicant borrowing (do rationed get credit elsewhere?) • applicant revenues • applicant consumption smoothness • NOT needed to measure impacts using this method: • No baseline survey needed • No perfect compliance with treatment assignment needed: workable if some derationed borrowers get loans, or vice versa • Can use statistical technique called “Intent to Treat” to measure impacts based on remaining random variation
Measurement Strategy Formally: (1) Yi = a + bderationedi + driski + fmonthi + ei • Y is an outcome from admin or survey data • derationed is randomly assigned by Lender • risk conditions the randomization (“reversal”) probability on the Lender’s assessment of how close to creditworthy • month partials out aggregate shocks in the time series
Derationing Implementations • Completed in South African consumer loan market • Underway in Filipino microenterprise loan market • Planning in Peruvian microenterprise loan market
Market Settings • Microenterprise credit market in Metro Manila • For-profit lender • Individual liability • Partly secured • Primarily small grocery/convenience stores • No targeting
Market Settings • Consumer loan market in South Africa • For-profit lender regulated by Microfinance Regulatory Council • Unsecured • Individual liability • High-risk • Short-term (4 months), fixed repayments • Expensive (11.75% monthly, simple) • Untargeted, “working poor” clientele
Implementation Details:Engineering Randomness • South Africa: derationing by random reversal (or not) of rejections in grey area • Metro Manila: derationing via implementation of new credit scoring model with random component in grey area
What’s in it for the Lenders? • Improve profitability by careful identification of the profitability frontier • What does the marginal profitable/break-even applicant look like • “Pilot approach” • Systematic and gradual changes • Improve efficiency by process innovation • Introduction of credit scoring • Experimentation and the learning organization • Democratization of approach used by sophisticated firms • ICIC, Green Bank
Preliminary Results fromSouth African Implementation • Derationing does increase borrowing over the 6-12 months following the experiment • Some positive impacts 6-12 months out: • Derationed households have less hunger • Derationed households more likely to maintain formal employment • No negative impacts on households • But power issues: small sample, so imprecise estimation of null effects • Derationed loans did have substantially worse repayment. • Profitability?
Beyond Risk Assessment:Access Broadly Defined Several other aspects of financial product delivery affect access: • Loan pricing: targeted groups may have different takeup elasticities • Dehijia et al vs. Karlan-Zinman • Maturity & loan amount elasticities may dwarf price elasticities for constrained borrowers • Karlan-Zinman; Attanasio et al
Access Broadly Defined • Efficiency-Sustainability-Access nexus: • Risk assessment (credit scoring) • Enforcement & monitoring experiment in Peru (Karlan, Mullainathan,and Zinman)
Access Broadly Defined: Savings • Do consumers have difficulty saving? • Self-control; Household control • Other motivation and follow-through problems • Then savings takeup decision critical: what drives it? • Product presentation: • Mental accounting (KMZ puzzles experiment) • Marketing and framing a la BKMSZ on loans • Product features (reminders, SMART, SEED) • Distribution channels: “Impulse Savings”
Beyond Evaluation: Why? • Interventions: how do we know what to try in the first place? • Intuition • Theory • Anecdata • Past Evaluations • Presence or absence underlying market failures interventions are designed to solve
Beyond Evaluation: Why? • Scientific evidence on empirical relevance of specific market failures also rare • Important to build into evaluations, experimentation • Example: measuring adverse selection and moral hazard • Most important theoretical motivations for microcredit • Little clean evidence on importance of either friction
Beyond Evaluation:Identifying Market Failures • Karlan-Zinman pricing experiment in South Africa (2005a, 2005b) • Derive profit-maximizing interest rate by randomizing interest rates • This requires one dimension of interest rate variation • Also measure why optimal interest rate is where it is • Demand elasticities • Repayment elasticities due to separate effects of adverse selection and moral hazard • Requires three dimensions of interest rate variation
Why invest in the why of interventions? • Policy • E.g.: adverse selection and moral hazard have different remedies • Practice: • Investments in screening? • Investments in enforcement? • Design of future interventions • Ongoing experimentation as process innovation
Experiment Evaluate Innovate Experimentation &the Learning Organization:A Virtuous Cycle