This paper explores differences in the frequency with which students from different schools reach high levels of math achievement. Data from the American Mathematics Competitions is used to produce counts of high-scoring students from more than two thousand public, coeducational, non-magnet,...

The paper advances the log-generalized gamma distribution as a suitable generator of conditional skewness. Based on the NYSE composite daily returns an asMA-asQGARCH model along with skewness dynamics is estimated. The results indicate a skewness that varies between sizeable negative skewness...

This paper studies drivers of high-frequency (daily) dynamics of the South African rand vis-à-vis the dollar from January 2001 to July 2007. We find strong nonlinear effects of commodity prices, perceived country and emerging market risk premium and changes in the dollar-euro exchange rate on...

This paper puts the original Reinhart-Rogoff dataset, made public by Herndon et al. (2013), to a formal econometric test to pin down debt threshold endogenously. We show that the nonlinear relation from debt to growth is not very robust. Taken with a pinch of salt, our results suggest, however,...

For forecasting and economic analysis many variables are used in logarithms (logs). In time series analysis this transformation is often considered to stabilize the variance of a series. We investigate under which conditions taking logs is beneficial for forecasting. Forecasts based on the...

In this paper we specify a linear Cliff and Ord-type spatial model. The model allows for spatial lags in the dependent variable, the exogenous variables, and disturbances. The innovations in the disturbance process are assumed to be heteroskedastic with an unknown form. We formulate a multi-step...