Competitive trading in forward and spot markets under yield uncertainty
研究产量不确定性如何影响远期与现货混合市场的均衡结果，发现产量风险增加可能使企业减少远期销售、降低现货价格波动，但远期市场会加剧现货价格波动。
Many agricultural commodities are traded in both forward and spot markets. This paper studies the interplay of random yield and forward market in a hybrid market with spot and forward transactions. We examine two main questions: (a) How does yield uncertainty (yield risk and yield correlation) affect the equilibrium outcome in this hybrid market? (b) How does the existence of a forward market influence the firms' strategic behaviors and spot price volatility, and how does yield uncertainty mediate the role of the forward market? In our baseline model that considers two firms and no withholding behavior by the firms, it is found that as yield risk increases, firms may sell less in the forward market, and counterintuitively, higher yield risk may benefit firms and make the spot price less volatile. The existence of a forward market leads to greater spot price volatility; that is, a forward market destabilizes spot prices. We identify a mitigating effect of yield variability, but an enhancing effect of yield correlation, on the role of the forward market. Finally, we extend our baseline model to the case with more than two firms and the setting where the firms may withhold some products and demonstrate that some of the key results in the baseline model carry over to these extensions. Nevertheless, the firms' withholding behavior represents a new driving force that changes some results. For example, the decreasing trend of spot price volatility in yield risk disappears in the withholding model.