Experimental Design Details
The study is implemented through village-based lab-in-the-field sessions conducted with women members of Village Savings and Loan Associations (VSLAs). Within each session, participants first complete a baseline survey capturing demographic characteristics, agricultural practices, prior exposure to digital agricultural technologies (DATs), and baseline knowledge of soil fertility management practices.
Participants are then randomly assigned at the individual level within session to one of three arms: (i) SMS and voice-based delivery of agricultural advisory content on soil types and soil fertility management practices (Treatment 1), (ii) delivery of the same advisory content via a smartphone application (Zaulimi) (Treatment 2), or (iii) an active control group that views a short WASH (water, sanitation, and hygiene) video unrelated to agriculture. The informational content is held constant across treatment arms in order to isolate the effect of delivery modality.
Immediately following treatment exposure, all participants complete an endline survey measuring agricultural knowledge, perceived comprehension of the information received, perceived usability of the delivery channel, confidence in applying the information (self-efficacy), and intended behavioural responses.
Participants then undertake an incentivized revealed preference task in which they make a real choice between an agricultural input (fertilizer) and a consumption good (sugar), allowing assessment of short-run investment-related decision-making following exposure to advisory information.
In a subset of villages, participants also complete a discrete choice experiment (DCE) module at baseline and endline to elicit stated preferences over key attributes of digital agricultural advisory platforms, including delivery format, language, interactivity, contextualization, market information, and cost. The DCE is followed by additional questions capturing attribute attendance and preferred DAT design features.
Random assignment is implemented using computer-assisted survey software, with approximately equal allocation across study arms within each session.