ABSTRACT The aggregate distortions to the incentives of South African agricultural producers have been estimated, but these measures have not been disaggregated to reveal individual agents’ incentives in a vertical value chain. In order to do this, the aggregate distortion estimates were first updated to account for the past decade, and then the wheat value chain was disaggregated for the marketing years starting in October 2000 and ending in September 2014. The results highlight how aggregate distortion estimates as developed by Anderson et al. (2006) and calculated by Kirsten, Edwards, and Vink (2009) for South African agriculture in essence mask the inter agent distortion differences in a vertical value chain. The focus in this article is on the measurement of the disaggregated distortions, while further research on the structure of the industry (its competitiveness at all levels of the value chain) and the role of the exchange rate is required to increase our understanding of the real incentives that confront these agents.

中文翻译：

---

南非农业激励机制的扭曲：小麦产业的案例研究

摘要 南非农业生产者激励的总体扭曲已被估计，但这些措施尚未分解以揭示垂直价值链中个体代理的激励。为此，首先更新了总失真估计以考虑过去十年，然后对从 2000 年 10 月开始到 2014 年 9 月结束的销售年度的小麦价值链进行分解。结果突出显示了总失真估计如何作为由安德森等人开发。（2006 年）以及由 Kirsten、Edwards 和 Vink（2009 年）计算的南非农业在本质上掩盖了垂直价值链中主体间扭曲的差异。本文的重点是测量分解的失真，