Experimental Design
The experimental design is a cluster randomized controlled trial with four treatment arms (T0, T1, T2, and T3) across 240 maize-producing villages in northern Nigeria. Farmers randomly assigned to the four treatment arms are exposed to the following:
T0 (Control): AI chatbot that provides recommended fertilizer package (rate, type, timing, and basic “how-to”), rainfall forecasts, agronomic and investment returns guidance; advice is deterministic and point-estimate based; no stochastic production or price content.
T1 (Risk-Aware Advisory): T0 + explicit stochasticity in production and market outcomes, scenario-based returns, and risk-adjusted profitability guidance.
T2 (Risk-Aware + Passive Explainer): T1 + short passive video explaining risk concepts and how the chatbot can answer probabilistic questions. Holds total dosage and exposure to risk content roughly constant relative to T3.
T3 (Risk-Aware + Risk-Inquiry Priming): T1 + interactive incentivized investment game in which farmers choose fertilizer investments under uncertainty, observe realized payoffs, and are nudged toward asking the chatbot about return likelihoods and distributions