Fig 1.
Volatility of the global representative stock index: 2005–2010.
The volatility of the global representative stock index from the year 2005 to 2010. They are FTSE Europe Pioneer 300 Index, Shanghai Composite Index, FTSE Straits Times Index, S & P 500 index, European Stoxx 600 index and Dow Jones Industrial Average index.
Table 1.
This is the name of the 38 global main stock indexes in the world. We collected from Yahoo! Finance. For the convenience of expression and computation later, we numbered it. For each item, the front is its serial number, followed by the corresponding stock index.
Fig 2.
Correlation coefficient matrix before the crisis.
This is the correlation coefficient matrix before the crisis. This is corresponding to data in S3 File. The vertical axis and the horizontal axis all represent the 38 stock indexes. The redder the color of the block area, the greater the correlation coefficient. The bluer the color of the block area is, the smaller the correlation coefficient is.
Fig 3.
Correlation coefficient matrix during the crisis.
This is the correlation coefficient matrix during the crisis. This is corresponding to data in S3 File. The vertical axis and the horizontal axis all represent the 38 stock indexes. The redder the color of the block area, the greater the correlation coefficient. The bluer the color of the block area is, the smaller the correlation coefficient is.
Fig 4.
Correlation coefficient matrix after the crisis.
This is the correlation coefficient matrix after the crisis. This is corresponding to data in S3 File. The vertical axis and the horizontal axis all represent the 38 stock indexes. The redder the color of the block area, the greater the correlation coefficient. The bluer the color of the block area is, the smaller the correlation coefficient is.
Fig 5.
Minimum spanning tree of network before the crisis.
The network before the crisis is divided into three areas of aggregation. They are American stock market, Asia Pacific& Australia stock market and European stock market. The lighter the color of the node is, the greater the degree of the node is. In addition, the thicker the edge is, the greater the weight is in the figure.
Fig 6.
Minimum spanning tree of network during the crisis.
The network during the crisis is divided into three areas of aggregation. They are American stock market, Asia Pacific& Australia stock market and European stock market. The lighter the color of the node is, the greater the degree of the node is. In addition, the thicker the edge is, the greater the weight is in the figure.
Fig 7.
Minimum spanning tree of network after the crisis.
The network after the crisis is divided into three areas of aggregation. They are American stock market, Asia Pacific& Australia stock market and European stock market. The lighter the color of the node is, the greater the degree of the node is. In addition, the thicker the edge is, the greater the weight is in the figure.
Table 2.
Network topology characteristic parameter of three periods.
These parameters include average threshold, number of nodes, number of edges, clustering coefficient and characteristic path length for three different periods.
Table 3.
Small world characteristic statistical parameter.
These parameters include ratio gamma γ, ratio lambda λ, sigma σ, clustering coefficient and characteristic path length in the random network with the same scale.
Fig 8.
The influence of the threshold on the modularity Q.
This is the modularity variation curve of the network in three different periods under different threshold conditions. The values greater than about 0.3 appear to indicate significant community structure.
Fig 9.
Hierarchical clustering structure before the crisis.
This is the hierarchical clustering structure before the crisis. The horizontal axis represents the stock index, while the vertical axis represents the distance between these indices. The network could be divided into four communities whose member is shown in purple, red, green and black line.
Fig 10.
Hierarchical clustering structure after the crisis.
This is the hierarchical clustering structure after the crisis. The horizontal axis represents the stock index, while the vertical axis represents the distance between these indices. The network could be divided into four communities whose member is shown in purple, red, green and black line.