Testing for the Cointegrating Rank of a VAR Process with Level Shift at Unknown Time

A systems cointegration rank test is proposed that is applicable for vector autoregressive (VAR) processes with a structural shift at unknown time. The structural shift is modeled as a simple shift in the level of the process. It is proposed to estimate the break date first on the basis of a full unrestricted VAR model. Two alternative estimators are considered and their asymptotic properties are derived. In the next step the deterministic part of the process including the shift size is estimated and the series are adjusted by subtracting the estimated deterministic part. A Johansen type test for the cointegrating rank is applied to the adjusted series. The test statistic is shown to have a well‐known asymptotic null distribution that does not depend on the break date. The performance of the procedure in small samples is investigated by simulations.     

Performance of phase-I dose finding designs with and without a run-in intra-patient dose escalation stage

Dose-finding designs for phase-I trials aim to determine the recommended phase-II dose (RP2D) for further phase-II drug development. If the trial includes patients for whom several lines of standard therapy failed or if the toxicity of the investigated agent does not necessarily increase with dose, optimal dose-finding designs should limit the frequency of treatment with suboptimal doses. We propose a two-stage design strategy with a run-in intra-patient dose escalation part followed by a more traditional dose-finding design. We conduct simulation studies to compare the 3 + 3 design, the Bayesian Optimal Interval Design (BOIN) and the Continual Reassessment Method (CRM) with and without intra-patient dose escalation. The endpoints are accuracy, sample size, safety, and therapeutic efficiency. For scenarios where the correct RP2D is the highest dose, inclusion of an intra-patient dose escalation stage generally increases accuracy and therapeutic efficiency. However, for scenarios where the correct RP2D is below the highest dose, intra-patient dose escalation designs lead to increased risk of overdosing and an overestimation of RP2D. The magnitude of the change in operating characteristics after including an intra-patient stage is largest for the 3 + 3 design, decreases for the BOIN and is smallest for the CRM.     

PREDICTING STOCK MARKET BEHAVIOR THROUGH RULE INDUCTION: AN APPLICATION OF THE LEARNING-FROM-EXAMPLE APPROACH*

An artificial intelligence-based rule-induction approach to the analysis of stock market prediction is presented. A single investment analyst was used as the expert for this study. Predicting intermediate fluctuations in the movement of the market for nonconservative investors was selected as the decision to analyze. Commercially available rule-induction software was used to generate rules that predicted the market calls of the market analyst and the actual movements of the market. Rules predicting actual market movement performed better than rules predicting the analyst's calls and better than the analyst himself. Such an approach may prove useful in designing a decision support system for market analysts or in improving the decision-making processes of such analysts. The dynamic nature of the stock market represents a substantially different decision environment than those previously analyzed by learning-from-example (LFE) techniques. This study provides insights into the limits and applications of LFE approaches.     

Editorial: Ten Years After: The Third Sector and Civil Society in Central and Eastern Europe

VOLUNTAS: International Journal of Voluntary and Nonprofit Organizations -     

Order-picking in deep cold--physiological responses of younger and older females. Part 2: body core temperature and skin surface temperature

So far, it was unclear to what extent working in deep cold-storage depots has an influence on female order-pickers body core temperature and skin surface temperature considering different age groups. Physiological effects of order-picking in a chill room (+3°C) and cold store (-24°C) were examined on 30 female subjects (Ss), classified in two age groups (20- to 35- year-olds and 40- to 65-year-olds). The body core temperature was taken every 15 min at the tympanum and the skin surface temperature was recorded continuously at seven different positions. Working in the chill room induced a decrease of the body core temperature up to 0.5K in comparison to the value at the outset for both age groups which could be compensated by all Ss during the breaks. Working in the cold store caused a decline up to 1.1K for the younger Ss and 1.3K for the older Ss. A complete warming-up during the breaks was often not possible. Regarding the skin surface temperature, working in the chill room can be considered as unproblematic, whereas significantly lower temperatures at nose, fingers and toes, associated with substantial negative subjective sensations, were recorded while working in the cold store.     

Political regimes and the family: how sex-role attitudes continue to differ in reunified Germany

We exploit the German separation and later reunification to investigate whether political regimes can shape attitudes about appropriate roles for women in the family and the labor market. During the divided years, East German institutions encouraged female employment, while the West German system deterred women, in particular mothers, from full-time employment. Our results show that East Germans are significantly more likely to hold egalitarian sex-role attitudes than West Germans. Despite a scenario of partial policy convergence after reunification, we find no evidence for a convergence process in gender attitudes. Indeed, if anything, the gap in attitudes rather increased.     

Asymptotics of goodness-of-fit tests based on minimum p-value statistics

This paper provides some new results on the asymptotics of goodness-of-fit (GOF) tests based on minimum p-value statistics. In connection with detectability of sparse signals in high-dimensional data, various tests were proposed and investigated during the last decade, especially with respect to asymptotic properties. Minimum p-value GOF statistics were already investigated as minimum level attained statistics by Berk and Jones with respect to Bahadur efficiency. The distribution of minimum p-value GOF statistics is closely related to the distribution of higher criticism statistics, the distribution of the supremum of a normalized Brownian bridge, and the supremum of an Ornstein–Uhlenbeck process.