There is substantial empirical evidence that energy and financial markets are closely connected. As one of the most widely-used energy resources worldwide, natural gas has a large daily trading volume. In order to hedge the risk of natural gas spot markets, a large number of hedging strategies...

This paper provides a textbook example of integration between commodity markets, and the subsequent price convergence or absence thereof. We analyze price relations between spot markets for natural gas in Europe. We apply time-varying coefficient estimation applying the Kalman filter, to test...