This study is motivated by the need to understand how the rise of medium‐scale farms in Africa is affecting small‐scale farm households. Survey evidence over the past decade has shown a dramatic rise in the prevalence of ‘medium’ sized farms between 5 and 100 hectares, but smaller farms still constitute the vast majority of farms and rural households. Prior evidence highlights a co‐evolution between the concentration of landholdings, surplus production volumes, and entry of larger traders into the market. Whether these changes tend to impact on smallholders negatively, crowding them out of markets, for example, or positively, potentially opening new marketing channels, is an empirical question. Using a multi‐stage model for maize market participation in Zambia, we find that in areas where medium‐scale farms are growing, even the smaller farms are becoming more likely to sell maize, more likely to sell to the private sector, more likely to sell to larger traders, and expected sales amongst sellers are higher. On balance, the growth of medium‐scale farms and large‐scale traders seems to have positive spillover effects on nearby smallholder marketing options.

中文翻译：

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中型农场会改善赞比亚小农的市场准入条件吗？

本研究的动机是需要了解非洲中型农场的兴起如何影响小规模的农户。过去十年的调查证据表明，介于5到100公顷之间的“中型”农场的流行率急剧上升，但是较小的农场仍然构成了绝大多数的农场和农村家庭。先前的证据表明，土地所有权的集中，剩余生产量和较大贸易商进入市场之间存在共同演变。这些变化是否会给小农带来消极影响，例如将其挤出市场，还是会积极地打开新的营销渠道，这是一个经验性的问题。使用赞比亚玉米市场参与的多阶段模型，我们发现在中等规模农场正在成长的地区，即使是规模较小的农场，也越来越有可能出售玉米，更有可能出售给私营部门，更有可能出售给较大的贸易商，并且卖方之间的预期销售量也更高。总体而言，中型农场和大型贸易商的增长似乎对附近的小农销售选择具有积极的溢出效应。