In spite of mounting evidence about the growth of medium-scale farms (MSFs) across Africa, there is limited empirical evidence on their impact on neighbouring small-scale farms (SSFs). We examine the relationships between MSFs and SSFs, with particular focus on the specific mechanisms driving potential spillover effects. First, we develop a theoretical model explaining two propagating mechanisms: learning effects (training) and cost effects (reduced transactions cost). An empirical application to data from Nigeria shows that SSFs with training from MSFs tend to use higher levels of modern inputs (have higher productivity), and receive higher prices and income. The results also show that purchasing inputs from MSFs reduces the costs of accessing modern inputs and is associated with higher inorganic fertiliser use by SSFs. Our results suggest that the benefits of receiving training and purchasing inputs from MSFs are particularly important for very small-scale producers, operating less than 1 hectare of land. This implies that policies which promote the efficient operation of MSFs and encourage their interaction with SSFs can be an effective mechanism for improving the productivity and welfare of smallholder farms, hence reducing their vulnerability to extreme poverty.

中文翻译：

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中型农场能否支持小农商业化并改善福利？来自尼日利亚的证据

尽管有关中型农场 (MSF) 在整个非洲的增长的证据越来越多，但关于它们对邻近小型农场 (SSF) 的影响的实证证据有限。我们研究了 MSF 和 SSF 之间的关系，特别关注驱动潜在溢出效应的具体机制。首先，我们开发了一个理论模型来解释两种传播机制：学习效应（培训）和成本效应（降低交易成本）。对尼日利亚数据的实证应用表明，接受过 MSF 培训的 SSF 倾向于使用更高水平的现代投入（具有更高的生产率），并获得更高的价格和收入。结果还表明，从 MSFs 购买投入物可以降低获取现代投入物的成本，并且与 SSFs 使用更多的无机肥料有关。我们的结果表明，接受培训和从无国界医生那里购买投入物的好处对于经营土地不到 1 公顷的超小规模生产者尤为重要。这意味着促进 MSFs 有效运作并鼓励它们与 SSFs 互动的政策可以成为提高小农生产力和福利的有效机制，从而降低他们对极端贫困的脆弱性。