case of ARGARCH models, the approximation process chosen in this paper shows a better estimation of the stock price … development based on autoregressive models and, thus, more robust estimation results for the reaction to a regulatory change … because of the national process of governments’ adjustments. Thus, the estimation results provide evidence that companies …

to initiate adequate investment incentives. Using a two-equation estimation approach, a direct competition effect (more … still found, the estimation results confirm the idea of asymmetric substitutability between telecommunication …