Ratios of quadratic forms in correlated normal variables which introduce noncentrality into the quadratic forms are considered. The denominator is assumed to be positive (with probability 1). Various serial correlation estimates such as least-squares, Yule–Walker and Burg, as well as Durbin–Watson statistics, provide important examples of such ratios. The cumulative distribution function (c.d.f.) and density for such ratios admit saddlepoint approximations. These approximations are shown to preserve uniformity of relative error over the entire range of support. Furthermore, explicit values for the limiting relative errors at the extreme edges of support are derived.
A large proportion of the most viable time series models used in empirical finance for density and value-at-risk forecasting are estimated with maximum likelihood methods. By way of its definition, the likelihood implicitly places equal weight on each of the observations in the sample, but this need not be optimal, depending on the extent to which the model and the true data generating process deviate. For example, in the context of modeling financial asset returns, schemes that place relatively more weight on observations in the recent past result in considerable improvement of out-of-sample density forecasts, compared with the default of equal weights. If instead of accurate forecasting of the, entire density, interest is restricted to just downside risk and risk model validation, then it would seem wise to (also) place more weight on the negative observations in the sample. In this paper, such weighted likelihood schemes are proposed and demonstrated to yield considerable improvements in forecast accuracy using a variety of data sets and different GARCH models. Further improvement is realized by combining the two weighting schemes, giving rise to a doubly weighted asymmetric risk forecasting method or, in short, a DWARF-like method.
Empirische Untersuchungen zeigen, dass sich einfach strukturierte Produkte für die Anleger am meisten lohnen. Wegen mangelnder Transparenz seitens der Anbieter und wegen psychologischer Fehleinschätzungen kaufen viele Investoren aber oft komplexe und teure Vehikel.
Comments on the article by E. Brandstätter, G. Gigerenzer, and R. Hertwig. The authors discuss the priority heuristic, a recent model for decisions under risk. They reanalyze the experimental validity of this approach and discuss how these results compare with cumulative prospect theory, the currently most established model in behavioral economics. They also discuss how general models for decisions under risk based on a heuristic approach can be understood mathematically to gain some insight in their limitations. They finally consider whether the priority heuristic model can lead to some understanding of the decision process of individuals or whether it is better seen as an as-if model.
We extend the original form of prospect theory by Kahneman and Tversky from finite lotteries to arbitrary probability distributions, using an approximation method based on weak-⋆ convergence. The resulting formula is computationally easier than the corresponding formula for cumulative prospect theory and makes it possible to use prospect theory in future applications in economics and finance. Moreover, we suggest a method how to incorporate a crucial step of the “editing phase” into prospect theory and to remove in this way the discontinuity of the original model.
Das A und O beim Investieren ist, systematisch vorzugehen. Wer
dies unterlässt, tappt schnell in eine psychologische Falle und muss die Konsequenzen tragen. Deshalb verlassen sich viele Anleger bei der Suche nach der richtigen Strategie auf den Rat von Vermögensverwaltern. Jedoch beraten heute noch immer einige von ihnen auf Basis von Konzepten aus den fünfziger Jahren. Interessante und nützliche Erkenntnisse der Behavioural Finance sollten vermehrt berücksichtigt werden.
The British Industrial Revolution triggered a socioeconomic transformation whereby the landowning aristocracy was replaced by industrial capitalists rising from the middle classes as the economically dominant group. We propose a theory of preference formation under financial-market imperfections that can account for this pattern. Parents shape their children’s preferences in response to economic incentives. Middleclass families in occupations requiring effort, skill, and experience develop patience and work ethic, whereas upper-class families relying on rental income cultivate a refined taste for leisure. These class-specific attitudes, which are rooted in the nature of pre-industrial professions, become key determinants of success once industrialization transforms the economic landscape.
