The business performance of firms in the creative high-tech sector shows much variation. This paper examines whether the geographical location of such business firms influences the performance of these firms. The overarching analysis framework of this paper emerges from the recently developed...

This note discusses some aspects of the paper by Hu and Tsay (2014), “Principal Volatility Component Analysis”. The key issues are considered, and are also related to existing conditional covariance and correlation models. Some caveats are given about multivariate models of time-varying...

Many empirical studies have shown that factor models produce relatively accurate forecasts compared to alternative short-term forecasting models. These empirical findings have been established for different macroeconomic data sets and different forecast horizons. However, various specifications...

In 1997 two papers_new applying the metaheuristics Tabu Search (TS) and Heuristic Concentration (HC) tothe p-median problem were published in consecutive volumes of the European Journal of OperationalResearch. Here we apply the method of HC some of the data sets which were used for...