The Pick of the Crop: Agricultural Practices and Clustered Networks in Village Economies
Journal of the European Economic Association · 2025 · André Gröger、Yanos Zylberberg
中文摘要
本文研究社会网络如何塑造（或未能塑造）农业实践。我们利用了两类数据：（1）以明确划定的地块为嵌套层级、覆盖农业生产的独特普查数据；（2）越南农村四个重新安置村庄内部的社会网络数据。第一步，我们利用构成各村庄的少数几条街道内的住宅位置，从网络形成中提取外生变异（这些村庄的人口是通过交错分批的人口安置迁入形成的），并估计社会联系对采用高产作物的回报。我们发现了较大的网络乘数效应，这与较低的采用率表面上相矛盾。第二步，我们研究网络形成的结构以解释这一谜题：社会网络呈现出高度的同质性，异质家庭之间有价值的联系十分罕见。由于网络具有集群化特征，且农业实践的传播是动态且内生的，社会联系的回报呈现递减，而针对“中间人”的政策最能缓解这一问题。
Abstract
Abstract This paper studies how social networks (might fail to) shape agricultural practices. We exploit (1) a unique census of agricultural production nested within delineated land parcels and (2) social network data within four repopulated villages of rural Vietnam. In the first step, we extract exogenous variation in network formation from home locations within the few streets that compose each village (populated through staggered population resettlement), and we estimate the return to social links in the adoption of highly productive crops. We find a large network multiplier in apparent contradiction with low adoption rates. In the second step, we study the structure of network formation to explain this puzzle: Social networks display large homophily, and valuable links between heterogeneous households are rare. Due to the clustered nature of networks and the dynamic, endogenous propagation of agricultural practices, there are decreasing returns to social links, and policies targeting “inbetweeners” are most able to mitigate this issue.