Working Paper: CEPR ID: DP9340
Authors: Lori Beaman; Dean S. Karlan; Bram Thuysbaert; Christopher Udry
Abstract: In an experiment providing fertilizer grants to women rice farmers in Mali, we found that women who received fertilizer increased both the quantity of fertilizer they used on their plots and complementary inputs such as herbicides and hired labor. This highlights that farmers respond to an increase in availability of one input by re-optimizing other inputs, making it challenging to isolate the returns to any one input. We also found that while the increase in inputs led to a significantly higher level of output, we find no evidence that profits increased. Our results suggest that fertilizer's impact on profits is small compared to other sources of variation. This may make it difficult for farmers to observe the impact of fertilizer on their plots, and accordingly this affects their ability to learn about the returns to fertilizer and could affect their decision to adopt even in the absence of credit constraints.
Keywords: Agricultural Economics; Returns to Fertilizer
JEL Codes: O12; O13; Q12
Edges that are evidenced by causal inference methods are in orange, and the rest are in light blue.
| Cause | Effect |
|---|---|
| Lack of observable profit increases (E25) | Farmers' ability to learn about returns to fertilizer (Q16) |
| Fertilizer provision (Q16) | Quantity of fertilizer used (Q15) |
| Fertilizer provision (Q16) | Use of complementary inputs (herbicides and hired labor) (Q12) |
| Increase in inputs (E23) | Output level (C67) |
| Fertilizer provision (Q16) | Profits (D33) |