Determinants of spatial knowledge spillovers in Italian provinces

Statistical evidence suggests that the relevance of knowledge spillovers has increased over time. In this paper we focus on regional knowledge spillovers and adopt a new econometric transformation that allows inference on potential inter-regional knowledge spillovers, accounting for spatial interdependencies.Determinants of inter-regional knowledge spillovers are explained with a sample of 103 Italian provinces. We find that a region’s absorptive capacity, measured by local R&D expenditure and social capital, implies a reduction of outward knowledge spillovers.Identification is based on the use of Two Stages Least Squares and Fixed Effects estimates.     

Run length analysis of Shewhart charts applied to drifting processes under an integrative SPC/EPC model

Engineering Process Controllers (EPC) are frequently based on parametrized models. If process conditions change, the parameter estimates used by the controllers may become biased, and the quality characteristics will be affected. To detect such changes it is adequate to use Statistical Process Control (SPC) methods. The run length statistic is commonly used to describe the performance of an SPC chart. This paper develops approximations for the first two moments of the run length distribution of a one-sided Shewhart chart used to detect two types of process changes in a system that is regulated by a given EPC scheme: i) changes in the level parameter; ii) changes in the drift parameter. If the drift parameter shifts, it is further assumed that the form of the drift process changes from a linear trend under white noise (the in-control drift model) into a random walk with drift model. Two different approximations for the run length moments are presented and their accuracy is numerically analyzed. Received: August 1998     

Countercyclical contingent capital

We analyze the optimal capital structure of a bank issuing countercyclical contingent capital, i.e., notes to be converted into common shares in poor macroeconomic conditions. A comparison of the main effects produced by the countercyclical asset with the simple equity-debt capital structure, the non-countercyclical contingent capital and the countercyclical callable bond is conducted. We demonstrate that this type of asset reduces the spread of straight debt and is effective in reducing the asset substitution incentive. The reduction of bankruptcy costs is strong only when the countercyclicality feature is removed. Contingent capital is useful for macroprudential regulation and we show that the countercyclical feature is important depending on priorities (moderate the asset substitution incentive or reduce bankruptcy costs).