Analysis of the Propane Price Oriented Weighted Network Based on the Symbolic Pattern Representation of Time Series

As an essential chemical raw material and a cost-effective energy product, fluctuations in propane price has garnered significant attention in the energy market. This paper processes the original time series using a coarse-grained method and employs symbolic representation combined with the sliding window technique to represent fluctuation modes as nodes within a network. The weight and direction of the edges among the nodes are determined by the number and direction of the conversions among the modes, thereby mapping the original sequence of the propane price into the propane price oriented weighted network (PPOWN) by the symbolic patterns, which is an asymmetric network that has evolved from the symmetric network based on symmetry theory. The results indicate that the core fluctuation state of the PPOWN is concentrated in the first 0.96% of the nodes, exhibiting scale-free network characteristics and dynamic asymmetry. Nodes with greater strength are more closely interconnected, but not all early-appearing nodes possess great strength. The PPOWN demonstrates a short-range correlation (L¯=8.5405) and a highly linear growth trend in the cumulative time interval of the new nodes. Additionally, the nodes of the PPOWN display low betweenness, clustering coefficient, and strength, which significantly differ from the random and chaotic networks. The presence of these lower-strength nodes often signifies that the market is undergoing a transformation or transition period. By identifying and analyzing these nodes, subsequent propane price fluctuations can be predicted more effectively, enhancing market responsiveness.