This paper examines the role of speculative motives in the determination of commodity prices and specifically food related commodity prices. The motivation for this study is the considerable flow of funds into commodities, the widespread view that the process of financialization has led to greater levels of speculation and that speculation is the primary cause of regular spikes in food prices since the turn of the century. We consider two forms of short-term trading, a biasing influence (Manipulators) and a correcting influence (Speculators), relative to the fundamental price. While both forms of short-term trading are relevant, they are small in terms of their influence on overall prices. We do however find some evidence of an increased role being played by Manipulators during the period most associated with financialization.

本文研究了投机动机在确定商品价格，特别是与食品相关的商品价格中的作用。这项研究的动机是大量资金流入大宗商品，人们普遍认为金融化过程导致了更高水平的投机，而投机是世纪之交以来食品价格经常飙升的主要原因。我们考虑两种形式的短期交易，相对于基本面价格的偏向影响（操纵者）和修正影响（投机者）。虽然这两种形式的短期交易都是相关的，但它们对整体价格的影响很小。然而，我们确实发现了一些证据表明，在与金融化最相关的时期，操纵者所发挥的作用越来越大。