Habermas talking: An interview

Theory and Society -     

Modelling stochastic volatility using generalized t distribution

In modelling financial return time series and time-varying volatility, the Gaussian and the Student-t distributions are widely used in stochastic volatility (SV) models. However, other distributions such as the Laplace distribution and generalized error distribution (GED) are also common in SV modelling. Therefore, this paper proposes the use of the generalized t (GT) distribution whose special cases are the Gaussian distribution, Student-t distribution, Laplace distribution and GED. Since the GT distribution is a member of the scale mixture of uniform (SMU) family of distribution, we handle the GT distribution via its SMU representation. We show this SMU form can substantially simplify the Gibbs sampler for Bayesian simulation-based computation and can provide a mean of identifying outliers. In an empirical study, we adopt a GT–SV model to fit the daily return of the exchange rate of Australian dollar to three other currencies and use the exchange rate to US dollar as a covariate. Model implementation relies on Bayesian Markov chain Monte Carlo algorithms using the WinBUGS package.     

On the semantics of the motif “three hares chasing each other in a circle” on Jewish monuments in Eastern Europe

“Three hares chasing each other in a circle” is one of the most common and peculiar motifs in the murals of Eastern European wooden synagogues. This motif was not an invention of Jewish craftsmen, but rather was borrowed and adapted by them from European art. In the late eighteenth to early nineteenth century this motif appears in various Ashkenazi ritual objects and on the tombstones of Eastern European Jews in the same region, and even in those places where there were painted synagogues. What is the reason for the appearance of this strange motif on Jewish monuments? On some monuments the motif of the “three hares” paradoxically replaces the “three overlapping fish” which are depicted as the zodiacal sign of the month Nisan. On the tombstones the image hints at the name of the deceased. But its central place in the composition of murals is evidence that this motif has an important universal meaning. This analysis of the motif shows that it became an integral part of an artistic tradition and that its semantics were determined within a well-defined geographical and chronological framework.     

The Pre- and Post-1997 Well-Being of Hong Kong Residents

Since July 1997, Hong Kong has become a Special Administrative Region (SAR) under the sovereignty of China. This paper compares the social well-being of Hong Kong residents before and after the change of sovereignty by analyzing six sets of survey data collected between 1990 and 2001. These are six biennial territory wide Social Indicator Surveys conducted to collect subjective assessments of well-being of Hong Kong residents. Analysis of the survey data which are typically categorized subjective evaluations has to deal with the commonly encountered problems of direct quantification (Schuessler and Fisher, 1985) and incomplete data (Little R.J.A. and Rubin D.B., 2002, Statistical Analysis with Missing data (Wiley-Interscience, New Jersy). The problems are handled by applying optimal scaling and hot-deck imputation as recommended by Shen S.M. and Lai Y.L. (2001, Social Indicators Research 55, pp. 121-166). Different life domain measures as well as compound measures in the form of indices are studied. The data analysis indicates that the residents of Hong Kong were most satisfied in 1997 and least satisfied in 1995. It reveals that the sovereignty change had major impact on many life domains of the people of Hong Kong and the effect was compounded by the economic situation of the territory.