Evaluating Density Forecasts with an Application to Stock Market Returns

Density forecasts have become quite important in economics and finance. For example, such forecasts play a central role in modern financial risk management techniques like Value at Risk. This paper suggests a regression based density forecast evaluation framework as a simple alternative to other approaches. In simulation experiments and an empirical application to in- and out-of-sample one-step-ahead density forecasts of daily returns on the S&P 500, DAX and ATX stock market indices, the regression based evaluation strategy is compared with a recently proposed methodology based on likelihood ratio tests. It is demonstrated that misspecifications of forecasting models can be detected within the proposed regression framework. It is further demonstrated that the likelihood ratio methodology without additional misspecification tests has no power in many practical situations and therefore frequently selects incorrect forecasting models. The empirical results provide some evidence that GARCH-t models provide good density forecasts. The results further suggest that extensions of statistical models with fat-tailed conditional distributions to models that incorporate higher order conditional moments beyond the conditional variance might be appropriate to capture the empirical regularities in financial time series in some cases. -- Die Voraussagen von Dichten ist in verschiedenen ökonomischen Fragestellungen sehr wichtig geworden. Solche Voraussagen spielen zum Beispiel eine wichtige Rolle bei modernen Methoden des Risikomanagements im Finanzsektor. Dieses Papier schlägt vor, Dichte-Prognosen mithilfe einer Methode zu beurteilen, die auf einem Regressionsansatz beruht. In Simulationsexperimenten und empirischen Anwendungen auf Dichte-Prognosen für tägliche Erträge verschiedener Aktienindices (S&P 500, DAX, ATX) wird diese Methode mit einer verglichen, die auf likelihood ratio Tests beruht und die erst neulich vorgeschlagen wurde. Es zeigt sich, dass Fehlspezifikationen der Prognosemodelle mithilfe der hier vorgeschlagenen Methode entdeckt werden können. Dagegen hat die Methode, die auf likelihood ratio Test beruht, ohne zusätzliche Tests auf Fehlspezifikation in vielen praktischen Fällen keine Macht. Die empirischen Ergebnisse deuten darauf hin, dass GARCH-t-Modelle gute Dichte-Prognosen liefern. Weiterhin wird gezeigt, dass Erweiterungen von statistischen Modellen mit Verteilungen mit dicken Enden zu Modellen, die höhere Momente einbeziehen, geeignet sein können, um in manchen Fällen empirische Regelmäßigkeiten in Finanzzeitreihen abzubilden.Density forecasting,Forecast evaluation,Risk management,GARCH-models

The Percept Study:Illness Perceptions in Physiotherapy

In this thesis, a Dutch version of the Brief IPQ is presented to assess IPs in daily physiotherapy practice in The Netherlands. Further, a literature overview of the existing associations and prognosis of IPs on MSP and functioning is presented, and these associations in primary physiotherapy care in The Netherlands are explored. The impact of a matched care physiotherapy package, matched to dysfunctional IPs, and MSP and physical functioning is studied. In this thesis, three themes (ie. measurement, association / prediction and treatment) are explored for their contribution to physiotherapy management of MSP in general, and especially for low back pai

The benefits of joint and separable financial management of couples

Financial management differs across households and this has various consequences for the financial outcomes and well-being of partners in households. A study has been performed on the financial management of couples, in households with or without children, in which data from both partners was collected on having joint and separate bank accounts, syncratic (joint) and autonomic (separate) financial management, the drivers of financial management, and the occurrence of financial problems. Based on the data, four financial management styles were distinguished: syncratic/joint, maledominant, female-dominant, and autonomic financial management styles. In the syncratic financial management style, partners have a joint bank account and take most financial decisions together. In the male/female-dominant decision styles, one partner (either husband or wife) takes the main decisions about how to spend from the joint bank account. In the autonomic money-management style, both partners have their own bank accounts, and can make their own decisions. As a conclusion, we find that both syncratic money management and having a joint instead of separate bank accounts correlate with fewer financial problems compared to male-dominant money management and having separate bank accounts. Working together as partners of a couple is beneficial for financial management and for avoiding financial problems

The benefits of joint and separate financial management of couples

Financial management differs across households with consequences for financial outcomes and well-being of partners in households. A large-sample study has been performed, investigating the relationship between financial management of households and the occurrence of financial problems. To our knowledge, this is the first study on this relationship. Data from both partners was collected on having joint and separate bank accounts, on financial decision making, on drivers of financial management, and on financial outcomes. Based on the data, four financial management styles were derived: syncratic/joint, male-dominant, female-dominant, and autonomous financial management. In the syncratic style, partners have a joint bank account and take most financial decisions together. In the male/female-dominant styles, one partner (husband or wife) takes the main financial decisions. In the autonomous style, both partners have their own bank accounts and make their own decisions. As a conclusion, we find that syncratic financial management and having a joint instead of a separate bank account correlates with fewer financial problems, as compared with male-dominant money management and having separate bank accounts. Deciding together as partners is beneficial for the quality of financial management and for avoiding financial problems.</p

Treatment based classification systems for patients with non-specific neck pain:A systematic review

Objective: We aimed to identify published classification systems with a targeted treatment approach (treatment-based classification systems (TBCSs)) for patients with non-specific neck pain, and assess their quality and effectiveness. Design: Systematic review. Data sources: MEDLINE, CINAHL, EMBASE, PEDro and the grey literature were systematically searched from inception to December 2019. Study appraisal and synthesis: The main selection criterium was a TBCS for patients with non-specific neck pain with physiotherapeutic interventions. For data extraction of descriptive data and quality assessment we used the framework developed by Buchbinder et al. We considered as score of ≤3 as low quality, a score between 3 and 5 as moderate quality and a score ≥5 as good quality. To assess the risk of bias of studies concerning the effectiveness of TBCSs (only randomized clinical trials (RCTs) were included) we used the PEDro scale. We considered a score of ≥ six points on this scale as low risk of bias. Results: Out of 7664 initial references we included 13 studies. The overall quality of the TBCSs ranged from low to moderate. We found two RCTs, both with low risk of bias, evaluating the effectiveness of two TBCSs compared to alternative treatments. The results showed that both TBCSs were not superior to alternative treatments. Conclusion: Existing TBCSs are, at best, of moderate quality. In addition, TBCSs were not shown to be more effective than alternatives. Therefore using these TBCSs in daily practice is not recommended

Two-Step 3D-Guided Supramalleolar Osteotomy to Treat Varus Ankle osteoarthritis

Background: Success of valgus-type supramalleolar osteotomy (SMOT) depends on adequate correction of malalignment, which can be hard to achieve with current 2-dimensional (2D) planning and operative techniques. A personalized digital 3-dimensional (3D) workflow to virtually plan and perform a 2-step 3D-guided medial opening (MO) SMOT has the potential to improve precision of correction. Methods: Computed tomography (CT)-based Proplan medical 3D models were made to virtually plan the desired MO SMOT, and exported to 3-Matic medical to develop patient-specific 2-step cutting and wedge guides. Workflow accuracy was tested in this limited clinical pilot study (3 patients) by comparing the virtual planned position of the osteotomized distal tibial fragment with the I -year post-MO SMOT configuration. Two millimeters or less translation deviation in every plane was defined as accurate. Results: Primary outcome analysis of the osteotomized distal tibial fragment deviation showed a median translation in all planes of 0.7 (range 0-8.2) mm (interquartile range 1.55) with an excellent interrater reliability of the measurements (intraclass correlation coefficient 0.998). There was a strong reduction in ankle pain as reflected by an increase of the AOFAS-AH score and decrease of NRS pain score with an unrestricted hindfoot motion 1 year after surgery. Conclusion: 3D virtually planned bone cutting and wedge guides is a promising approach associated with minimal postoperative deviation from the desired correction in medial opening supramalleolar osteotomy

Impact of multi-micronutrient supplementation on growth and morbidity of HIV-infected South African children

Poor growth, micronutrient deficiencies and episodes of diarrhea and respiratory infections occur frequently in HIV-infected children. We investigated whether multi-micronutrient supplementation would improve the growth performance and reduce the number of episodes of diarrhea and/or of respiratory symptoms in HIV-infected children. In a double-blind randomized trial, HIV-infected South African children aged 4–24 months (n = 201) were assigned to receive multi-micronutrient supplements or placebo daily for six months. The children were assessed for respiratory symptoms or diarrhea bi-weekly; weights and heights were measured monthly. In total, 121 children completed the six month follow up study period (60%). A total of 43 children died; 27 of them had received supplements. This difference in mortality was not statistically significant (p = 0.12). Weight-for-height Z-scores improved significantly (p <0.05) among children given supplements compared with those given placebo (0.40 (0.09–0.71)) versus -0.04 (-0.39–0.31) (mean (95% CI)). Height-for-age Z-scores did not improve in both treatment groups. The number of monthly episodes of diarrhea in the placebo group (0.36 (0.26–0.46)) was higher (p = 0.09) than in the supplement group (0.25 (0.17–0.33)) and the number of monthly episodes of respiratory symptoms was significantly higher (p <0.05) among children on placebos (1.01 (0.83–1.79)) than those on supplements (0.66 (0.52–0.80)). Multi-micronutrient supplements significantly improved wasting and reduced the number of episodes of diarrhea and respiratory symptoms

De Algemene Verordening Gegevensbescherming

Effective Protection of Fundamental Rights in a pluralist worl