A Novel Integrated Measure for Energy Market Efficiency

This paper formulates a novel integrated measure for energy market efficiency, by investigating different aspects of the market performance. Different from most existing models focusing on one certain aspect, the novel measure especially takes into consideration the self-similarity (or system memo ability or long-term persistence) via fractality, the attractor properties in phase-space via chaos, and disorder state of data dynamics via entropy. In the proposed method, the most popular data analysis techniques of multi-fractal detrended fluctuation analysis, correlation dimension, and sample entropy are respectively conducted on the market returns to capture the corresponding features, and the entropy weight method is then used to generate the final integrated index. For illustration and verification, the proposed measure is applied to three typical energy markets analyses. The empirical results find that natural gas market and crude oil market are much more efficient than carbon market.