Do Bubbles Alter Contributions to Price Discovery? Evidence from the Chinese Soybean Futures and Spot Markets

Abstract

ABSTRACT The purpose of this study is to investigate whether bubbles have significantly influenced the performance of price discovery in Chinese soybean futures markets. To evaluate the performance of price discovery, we employ forecast error variance decomposition based on structural vector autoregression and directed acyclic graphs, using daily data from six price series of futures contracts expiring at different months and one spot soybean price for the past 13 years. Then, the full-period data are divided into bubble and non-bubble periods via the supremum augmented Dickey–Fuller test. The methods utilized on the full sample for price discovery are conducted again on two subperiods. Our empirical results show that price discovery in the Chinese soybean futures market performs much better in bubble periods and worse in non-bubble period compared to the full period, indicating that bubbles have significantly influenced the performance of price discovery in Chinese soybean futures markets.