Specific-to-general predictor selection in approximate autoregressions—Monte Carlo evidence and a large scale performance assessment with real data

This paper describes the performance of specific-to-general composition of forecasting models that accord with (approximate) linear autoregressions. Monte Carlo experiments are complemented with ex-ante forecasting results for 97 macroeconomic time series collected for the G7 economies in Stock and Watson (J. Forecast. 23:405–430, 2004). In small samples, the specific-to-general strategy is superior in terms of ex-ante forecasting performance in comparison with a commonly applied strategy of successive model reduction according to weakest parameter significance. Applied to real data, the specific-to-general approach turns out to be preferable. In comparison with successive model reduction, the successive model expansion is less likely to involve overly large losses in forecast accuracy and is particularly recommended if the diagnosed prediction schemes are characterized by a medium to large number of predictors.     

Sensitivity Analysis to Evaluate the Impact of Uncertain Factors in a Scenario Tree Model for Classical Swine Fever Introduction

Introduction of classical swine fever virus (CSFV) is a continuing threat to the pig production sector in the European Union. A scenario tree model was developed to obtain more insight into the main risk factors determining the probability of CSFV introduction (P(CSFV)). As this model contains many uncertain input parameters, sensitivity analysis was used to indicate which of these parameters influence model results most. Group screening combined with the statistical techniques of design of experiments and meta-modeling was applied to detect the most important uncertain input parameters among a total of 257 parameters. The response variable chosen was the annual P(CSFV) into the Netherlands. Only 128 scenario calculations were needed to specify the final meta-model. A consecutive one-at-a-time sensitivity analysis was performed with the main effects of this meta-model to explore their impact on the ranking of risk factors contributing most to the annual P(CSFV). The results indicated that model outcome is most sensitive to the uncertain input parameters concerning the expected number of classical swine fever epidemics in Germany, Belgium, and the United Kingdom and the probability that CSFV survives in an empty livestock truck traveling over a distance of 0-900 km.     

Organisationsformen sozialer Hilfstätigkeit im Spiegel der wechselseitigen Wahrnehmung von hauptamtlichen und ehrenamtlichen Bewährungshelfern

The current development of the social sector is marked by a transformation of basic conditions, which is expressed in terms of an increasing cost pressure and an enhancement of status and a structural change of voluntary work. This paper addresses the question which patterns of mutual perception professional and voluntary social workers develop under such circumstances. Considering the Austrian probation service as example the social climate between professional and voluntary social workers is analysed. The main finding is that the mentioned transformations do not necessarily generate a conflict between vocational and non-vocational staff. Although the tasks of professional and voluntary probation officers are partially overlapping they view themselves mutually as enrichment and supplement and not as rivals. The extent of individual experiences of acceptance and appreciation may be identified as a background factor for the cooperative climate. Self-experienced acceptance and appreciation inhibits negative attitudes towards the other group.     

Voluntas: an editorial statement

Helmut Anheier is Assistant Professor of Sociology at Rutgers University, New Brunswick, New Jersey, USA     

Wertesynthese-Funktional oder dysfunktional?

Der Beitrag knüpft an den Kommentar zu einem Artikel von Sigrid Ro?teutscher durch Helmut Thome an (vgl. der Beitrag „‚Wertesynthese’: Ein unsinniges Konzept?” in KZfSS 57: 333–341). Er setzt der Grundsatzkritik Sigrid Ro?teutschers an der „Wertesynthese” (vgl. die Beitr?ge „Von Realisten und Konformisten — Wider die Theorie der Wertesynthese” in KZfSS 56: 407–432 und „Kein unsinniges Konzept, sondern traurige Realit?t” in KZfSS 57: 543–549) eine Beschreibung der Entstehungsgeschichte des Konzeptes der Wertesynthese und ihrer theoretischen Grundlagen entgegen. Weiterhin erfolgt eine Darstellung des aktuellen Erkenntnisstandes zur Wertesynthese. Es soll gezeigt werden, dass Konzept und Realit?t der „Wertesynthese” eine aussichtsreiche Forschungs-und Gesellschaftsperspektive er?ffnen.     

On the Onassis problem

A decision problem is by convention characterized by its outcome matrix and by a subsequent utility evaluation. In trying to set up an outcome matrix based on wealth values it may occur that due to ambiguities inherent in the decision problem it is not clear which standard of value (or numéraire) should be used in order to measure wealth. A typical example of this kind is Stützel's so called Onassis Paradox. We show that problems of this kind can be solved within the conventional framework of decision theory. The analysis proceeds in two steps. First, state-dependent utility functions are derived; second, a model for evaluating these utility functions is presented.     

Gender discrimination and efficiency in marriage: the bargaining family under scrutiny

We consider a repeated family bargaining model that links the topics of employment and households. A key aspect of the model is that marital bargaining power is determined endogenously. We show that: (1) the efficiency of household decisions is sometimes inversely related to the prevailing degree of gender discrimination in labor markets; (2) women who are discriminated against have difficulty enforcing cooperative household outcomes because they may be extremely limited to credibly punish opportunistic behavior by their male partners; (3) the likelihood that sharing rules such as “equal sharing” are maintained throughout a marriage relationship is highest when men and women face equal opportunities in labor markets. Responsible editor: Deborah Cobb-Clark     

Problems related to confidence intervals for impulse responses of autoregressive processes

Confidence intervals for impulse responses computed from autoregressive processes are considered. A detailed analysis of the methods in current use shows that they are not very reliable in some cases. In particular, there are theoretical reasons for them to have actual coverage probabilities which deviate considerably from the nominal level in some situations of practical importance. For a simple case alternative bootstrap methods are proposed which provide correct results asymptotically.