Wei-Xing Zhou

• PhD
• Professor (Full) at East China University of Science and Technology

The stability of the global food supply network is critical for ensuring food security. This study constructs an aggregated international food supply network based on the trade data of four staple crops and evaluates its structural robustness through network integrity under accumulating external shocks. Network integrity is typically quantified in...

Delving into food security and food supply resilience requires a deep insight of the international crop trade dynamics, yet the complex patterns behind them are currently in the mist. This paper examines the determinants of the international crop trade networks, where complex dependencies and higher-order effects originating from hierarchical struc...

It is important to maintain the resilient international food trade network for food security. We have constructed the international trade networks of maize, rice, soybean, and wheat based on bilateral flows data between economies. Drawing on information theory, we have measured their dynamic resilience based on efficiency and redundancy during 1986...

The study examines the return connectedness between climate policy uncertainty (CPU), clean energy, fossil energy, and food markets. Using the time-domain method of Diebold and Yilmaz (2012) and frequency-domain methods of Barun{\'{i}}k and K{\v{r}}hl{\'{i}}k (2018), we find substantial spillover effects between these markets. Furthermore, high fre...

We investigate the extreme return connectedness between the food, fossil energy, and clean energy markets using the quantile connectedness approach, which combines the traditional spillover index with quantile regression. Our results show that return connectedness at the tails (57.91% for the right tail and 61.47% for the left tail) is significantl...

This paper investigates the risk spillovers among AI ETFs, AI tokens, and green markets using the R2 decomposition method. We reveal several key insights. First, the overall transmission connectedness index (TCI) closely aligns with the contemporaneous TCI, while the lagged TCI is significantly lower. Second, AI ETFs and clean energy act as risk tr...

Stable and efficient food markets are crucial for global food security, yet international staple food markets are increasingly exposed to complex risks, including intensified risk contagion and escalating external uncertainties. This paper systematically investigates risk spillovers in global staple food markets and explores the key determinants of...

This study investigates the relationships between agricultural spot markets and external uncertainties through multifractal detrending moving-average cross-correlation analysis (MF-X-DMA). The dataset contains the Grains & Oilseeds Index (GOI) and its five subindices for wheat, maize, soyabeans, rice, and barley. Moreover, we use three uncertainty...

This study examines contemporaneous and lagged spillover effects in BRICS staple grain futures markets and their linkages with U.S. markets. The results show that contemporaneous spillovers dominate, while net spillovers are driven by lagged connectedness. Systemic risk is lower in intra-BRICS markets compared to those including the U.S., highlight...

This study examines the quantile connectedness among grain futures markets in BRICS and international markets, with a particular focus on the ongoing and escalating impacts of the Russia-Ukraine conflict. The findings reveal significant heterogeneity in spillover effects across different quantiles and market conditions. Specifically, the time-varyi...

Resilience serves to assess the ability of financial markets to resist external shocks. The intensity and duration, used to indicate resilience, are calculated for China's financial markets in this paper, focusing on the performance of each financial market during and after several crises. Given that climate issues have been recognized as an import...

This study investigates the relationships between agricultural spot markets and external uncertainties via the multifractal detrending moving-average cross-correlation analysis (MF-X-DMA). The dataset contains the Grains \& Oilseeds Index (GOI) and its five sub-indices of wheat, maize, soyabeans, rice, and barley. Moreover, we use three uncertainty...

With economic globalization and the financialization of agricultural products continuing to advance, the interconnections between different agricultural futures have become closer. We utilize a TVP‐VAR‐DY model combined with the quantile method to measure the risk spillover between 11 agricultural futures in the United States and China from July 9,...

The strategic orchestration of football matchplays profoundly influences game outcomes, motivating a surge in research aimed at uncovering tactical nuances through social network analysis. In this paper, we delve into the microscopic intricacies of cooperative player interactions by focusing on triadic motifs within passing networks. Employing a da...

Food security is a critical issue closely linked to human being. With the increasing demand for food, international trade has become the main access to supplementing domestic food shortages, which not only alleviates local food shocks, but also exposes economies to global food crises. In this paper, we construct four temporal international crop tra...

Food supply stability is crucial to ensuring food security for economies, especially those with insufficient domestic food production. To safeguard against potential shortages, food imports are becoming increasingly important. Food import shocks have significant impacts on targeted economies. Using import trade data for four staple crops (maize, ri...

The Russia-Ukraine conflict is a growing concern worldwide and poses serious threats to regional and global food security. Using monthly trade data for maize, rice, and wheat from 2016/1 to 2023/12, this paper constructs three international crop trade networks and an aggregate international food trade network. We aim to examine the structural chang...

With the frequent occurrence of black swan events, global energy security situation has become increasingly complex and severe. Assessing the resilience of the international oil trade network (iOTN) is crucial for evaluating its ability to withstand extreme shocks and recover thereafter, ensuring energy security. We overcomes the limitations of dis...

Extreme events are ubiquitous in nature and social society, including natural disasters, accident disasters, crises in public health (such as Ebola and the COVID-19 pandemic), and social security incidents (wars, conflicts, and social unrest). These extreme events will heavily impact financial markets and lead to the appearance of extreme fluctuati...

The temporal rich club (TRC) phenomenon is widespread in real systems, forming a tight and continuous collection of the prominent nodes that control the system. However, there is still a lack of sufficient understanding of the mechanisms of TRC formation. Here we use the international N-nutrient trade network as an example of an in-depth identifica...

The statistical properties of the international trade networks of all commodities as a whole have been extensively studied. However, the international trade networks of individual commodities often behave differently. Due to the importance of pesticides in agricultural production and food security, we investigated the evolving community structure i...

The importance of fertilizers to agricultural production is undeniable, and most economies rely on international trade for fertilizer use. The stability of fertilizer trade networks is fundamental to food security. However, quantifying the temporal stability of a fast-growing system, such as the international fertilizer trade, requires a multi-dime...

Being the world's most popular sport, football research has traditionally concentrated on empirical summaries or statistics, with only limited data available in the past. In recent years, social network analysis has been applied to a variety of fields, which also brings new perspectives to the study of football spots. In this paper, we survey the l...

Grains account for more than 50% of the calories consumed by people worldwide, and military conflicts, pandemics, climate change, and soaring grain prices all have vital impacts on food security. However, the complex price behavior of the global grain spot markets has not been well understood. A recent study performed multifractal moving average an...

Grains account for more than 50% of the calories consumed by people worldwide, and military conflicts, pandemics, climate change, and soaring grain prices all have vital impacts on food security. However, the complex price behavior of the global grain spot markets has not been well understood. A recent study performed multifractal moving average an...

The circulation process of agro-products plays a pivotal role in ensuring food security. However, factors that drive the agro-products circulation are still lacking of investigation. Here, we build three circulation networks of grains, vegetables, and fruits between cities in China based on 7,913,054 online freight orders and explore how the sector...

Liver injury may cause many diseases, such as non-alcoholic fatty liver disease (NAFLD). Acetochlor is one of the representative chloroacetamide herbicides, and its metabolite 2-chloro-N-(2-ethyl-6-methyl phenyl) acetamide (CMEPA) is the main form of exposure in the environment. It has been shown that acetochlor can cause mitochondrial damage of He...

N-nutrients in nitrogen fertilizers are a critical resource for modern agricultural production, with most economies relying on imports to secure adequate supplies. The N-nutrient trade system is vital for global food security and ecological safety. We analyzed the N-nutrient trade network from 1991 to 2020, using the perspective of the temporal ric...

The Grains and Oilseeds Index (GOI) and its sub-indices of wheat, maize, soyabeans, rice, and barley are daily price indexes reflect the price changes of the global spot markets of staple agro-food crops. In this paper, we carry out a visibility graph (VG) analysis of the GOI and its five sub-indices. Maximum likelihood estimation shows that the de...

By employing the Multifractal detrended fluctuation (MFDFA) analysis methods, the multifractal nature is revealed in the high-frequency data of two typical indexes, the Shanghai Stock Exchange Composite 180 Index (SH180) and the Shenzhen Stock Exchange Composite Index (SZCI). It is found that there is a statistically significant relationship betwee...

This paper combines the Copula-CoVaR approach with the ARMA-GARCH-skewed Student-t model to investigate the tail dependence structure and extreme risk spillover effects between the international agricultural futures and spot markets, taking four main agricultural commodities, namely soybean, maize, wheat, and rice as examples. The empirical results...

Pesticides are a kind of agricultural input, whose use can greatly reduce yield loss, regulate plant growth, effectively liberate agricultural productivity, and improve food security. The availability of pesticides in economies all over the world is ensured by pesticide redistribution through international trade and economies play different roles i...

Energy security and energy trade are the cornerstones of global economic and social development. The structural robustness of the international oil trade network (iOTN) plays an important role in the global economy. We integrate the machine learning optimization algorithm, game theory, and utility theory for learning an oil trade decision-making mo...

International food trade is a growing complement to gaps in domestic food supply and demand, but it is vulnerable to disruptions due to some unforeseen shocks. This paper assembles the international crop trade networks using maize, rice, soybean, and wheat trade data sets from 1986 to 2020. We assess the importance of economies using multidimension...

Ensuring food supply stability is key to food security for economies, and food imports become increasingly important to safeguard food supplies in economies with inadequate food production. Food import shocks have significant impacts on targeted economies. Using import trade data of four staple crops (maize, rice, soybean, and wheat) from 1986 to 2...

Pesticides are important agricultural inputs to increase agricultural productivity and improve food security. The availability of pesticides is partially achieved through international trade. However, economies involved in the international trade of pesticides are impacted by internal and external shocks from time to time, which influence the redis...

Fertilizer availability is crucial for global food security, and international fertilizer trade plays a vital role in reallocating fertilizers across multiple economies. However, the stability of international fertilizer trade relationships between economies has not been studied. Using 29 year records of the global fertilizer trade from 1990 to 201...

Financial risk is spread and amplified through the interconnectedness among financial institutions. We apply a time-varying parameter vector autoregression model to analyze the dynamic spillover effects in the Chinese financial system. We find that the 2017 house price control policies have significantly increased the risk of China’s financial syst...

The international pesticide trade network (iPTN) is a key factor affecting global food production and food security. The trade relationship is a key component in iPTNs. In a complex international trade environment, we model the impacts of uncertain factors such as trade wars, economic blockades and local wars, as removing vital relationships in the...

The multifractal nature of agriculture-related stocks and derivatives has been extensively studied. However, due to the scarcity and lack of representativeness of available data, the complex behaviors of the global grain spot markets are less researched. We perform multifractal detrending moving average (MF-DMA) analysis on the daily data of the Gr...

International seed trade networks (iSTNs) are complex networks formed by the trade of seeds between economies. We investigate the statistical properties of the international trade networks for maize seeds and rice seeds from the viewpoint of temporal directed and weighted networks. We find that most properties, including node and edge numbers, aver...

Food security is a critical issue closely linked to human being. With the increasing demand for food, international trade has become the main access to supplementing domestic food shortages, which not only alleviates local food shocks, but also exposes economies to global food crises. In this paper, we construct four temporal international crop tra...

The importance of fertilizers to agricultural production is undeniable, and most economies rely on international trade for fertilizer use. The stability of fertilizer trade networks is fundamental to food security. We use three valid methods to measure the temporal stability of the overall network and different functional sub-networks of the three...

We employ the generalized forecast error variance decomposition based on the vector autoregression model to investigate factors’ volatility spillovers. Furthermore, we investigate the relationship between factor volatility spillovers and their premia via the portfolio analysis. We find: (1) North America is the net transmitter of volatility shock,...

The statistical properties including community structure of the international trade networks of all commodities as a whole have been studied extensively. However, the international trade networks of individual commodities often behave differently. Due to the importance of pesticides in agricultural production and food security, we investigate the e...

With the growing demand for energy, the importance of oil as a major energy resource is increasingly evident, and trade has become the key to balancing energy supply and demand. We construct the evolving international oil trade network (iOTN) and analyze the structure and evolution characteristics of the network. Meanwhile, we identify different oi...

The fluctuations in global policy affect the volatility of international crude oil markets. It is quite meaningful to analyze the impact of policy uncertainty on crude oil market volatility from a global integration perspective in deep. This paper aims to examine whether the global uncertainty of economic policy (GEPU) and the uncertainty of uncert...

We revisit the dynamic relationship between domestic economic policy uncertainty and stock markets using the symmetric thermal optimal path (TOPS) method. We observe different interaction patterns in emerging and developed markets. Economic policy uncertainty drives the stock market in China, while stock markets play a leading role in the UK and th...

We derive the default cascade model and the fire-sale spillover model in a unified interdependent framework. The interactions among banks include not only direct cross-holding, but also indirect dependency by holding mutual assets outside the banking system. Using data extracted from the European Banking Authority, we present the interdependency ne...

This paper adopts the random matrix theory (RMT) to analyze the correlation structure of the global agricultural futures market from 2000 to 2020. It is found that the distribution of correlation coefficients is asymmetric and right skewed, and many eigenvalues of the correlation matrix deviate from the RMT prediction. The largest eigenvalue reflec...

Predicting the occurrence of tail events is of great importance in financial risk management. By employing the method of peak-over-threshold (POT) in extreme value theory (EVT) to identify the financial extremes, we perform a recurrence interval analysis (RIA) on these extremes. We find that the waiting time between consecutive extremes (recurrence...

In the international oil trade network, trade shocks triggered by extreme events may spread over the entire network along with the trade links of the central economies and even lead to the collapse of the whole system. To investigate the robustness of the international oil trade network under targeted attacks (i.e. shocks) to economies, we focus on...

Uncovering the risk-transmitting path within economic sectors in China is crucial for understanding the stability of the Chinese economic system, especially under the current situation of the China–US trade conflicts. In this paper, we aim to uncover the risk spreading channels by means of volatility spillovers within the Chinese sectors using stoc...

The efficiency of the international oil trade networks (iOTNs) is an important measure of the efficient redistribution of oil resources among various economies. Adopting cooperation strategies between economies can enhance the efficiency of the iOTNs. We design a series of trade cooperation strategies based on trade volumes, geographic locations an...

To meet the increasing demand for food around the world, pesticides are widely used and will continue to be widely used in agricultural production to reduce yield losses and maintain product quality. International pesticide trade serves to reallocate the distribution of pesticides around the world. We investigate the statistical properties of the i...

As a vital strategic resource, oil has an essential influence on the world's economy, diplomacy and military development. Oil resources are unevenly distributed. Therefore, trade is an important way to realize the allocation of oil resources on a global scale. This paper establishes a trading-based network model for international oil trade to study...

With increasing global demand for food, international food trade is playing a critical role in balancing the food supply and demand across different regions. Here, using trade datasets of four crops that provide more than 50% of the calories consumed globally, we constructed four international crop trade networks (iCTNs). We observed the increasing...

The development of logistics accelerates the transportation process, which in turn increases the exchanging efficiency between cities. To understand such exchanging interactions among cities, we build a city logistics network based on a unique data set, which contains millions of online freight orders spanning a period of one year. It is found that...

Weiqi, also called Go or Baduk, is regarded as the most complicated board game in the world. Weiqi playing has a very long history in East Asia. Its strategic thinking in decision-making even affects militarists there. The availability of the records of almost all Weiqi games in the past decades enables us to perform quantitative studies about this...

We model hierarchical cascades of failures among banks linked through an interdependent network. The interaction among banks include not only direct cross-holding, but also indirect dependency by holding mutual assets outside the banking system. Using data extracted from the European Banking Authority, we present the interdependency network compose...

Using a unique data set containing about 15.06 million truck transportation records in five months, we investigate the highway freight transportation diversity of 338 Chinese cities based on the truck transportation probability pij from one city to another. The transportation probabilities are calculated from the radiation model based on the geogra...

Stock markets exhibit different states due to internal and external shocks. It is of great significance to identify the status of global financial markets. Based on 48 global stock indices from 1996 to 2018, we constructed a global stock index transfer entropy network, which represents the information flow between stock markets in different economi...

This paper focuses on the horse race of weekly idiosyncratic momentum (IMOM) with respect to various idiosyncratic risk metrics. Using the A-share individual stocks in the Chinese market from January 1997 to December 2017, we first evaluate the performance of the weekly momentum and idiosyncratic momentum based on raw returns and idiosyncratic retu...

Nighttime lights (NTLs) have been used as a proxy for economic growth in recent years. To verify the effectiveness of NTL in measuring regional economies, this article studies the regional economic convergence phenomenon in China’s provinces by a comparative analysis of NTL data and GDP data from 1992 to 2013. It is found that there is a significan...

In the international oil trade network (iOTN), trade shocks triggered by extreme events may spread over the entire network along the trade links of the central economies and even lead to the collapse of the whole system. In this study, we focus on the concept of "too central to fail" and use traditional centrality indicators as strategic indicators...

We use 239-day trading-level data for a stock on the Shanghai Stock Exchange, including about 440,000 traders and 1.77 million trading relationships, to study the representation of traders in a trading network using the network representation learning method, and to identify different traders' local outlier factor (LOF). Based on the local outlier...

Abstract Empirical investor networks (EIN) proposed by Ozsoylev et al. are assumed to capture the information spreading path among investors. Here, we perform a comparative analysis between the EIN and the cellphone communication networks (CN) to test whether EIN is an information exchanging network from the perspective of the layer structures of e...

This study proposes an extension of the Asymmetric CoVaR method in Espinosa et al. (J Bank Finance 58: 471–485, 2015) to capture the time-varying asymmetric responses of the financial system to positive and negative shocks to individual institutions. Building on the extended method and considering a set of Chinese financial institutions, we assess...

Highway freight transportation (HFT) plays an important role in the economic activities. Predicting HFT networks is not only scientifically significant in the understanding of the mechanism governing the formation and dynamics of these networks, but also of practical significance in highway planning and design for policymakers and truck allocation...

Using a unique data set containing about 15.06 million truck transportation records in five months, we investigate the highway freight transportation diversity of 338 Chinese cities based on the truck transportation probability $p_{ij}$ from one city to the other. The transportation probabilities are calculated from the radiation model based on the...

This article investigates the effect of cross‐shareholdings on stock price synchronicity, as a measure of price informativeness, of the listed firms in the Chinese stock market. We gauge firms' levels of cross‐shareholdings in terms of centrality in the cross‐shareholding network. It is confirmed that it is through a noise‐reducing process that cro...

We examine the relation between daily order imbalance and stock returns in the Chinese stock market. We show that lagged order imbalance significantly and negatively predicts future stock returns. In addition, the predictive relation is robust for size and turnover subsamples, but stronger for small stocks and stocks with high turnover. Finally, we...

Uncertainty plays an important role in the global economy. In this paper, the economic policy uncertainty (EPU) indices of the United States and China are selected as the proxy variable corresponding to the uncertainty of national economic policy. By adopting the visibility graph algorithm, the four economic policy uncertainty indices of the United...