http://repub.eur.nl/res/org/9724/ List of Publications en http://repub.eur.nl/static-eur/img/logo.png http://repub.eur.nl http://repub.eur.nl/res/pub/39847/ 2014-04-15T00:00:00Z Accurate prediction of risk measures such as Value at Risk (VaR) and Expected Shortfall (ES) requires precise estimation of the tail of the predictive distribution. Two novel concepts are introduced that offer a specific focus on this part of the predictive density: the censored posterior, a posterior in which the likelihood is replaced by the censored likelihood; and the censored predictive likelihood, which is used for Bayesian Model Averaging. We perform extensive experiments involving simulated and empirical data. Our results show the ability of these new approaches to outperform the standard posterior and traditional Bayesian Model Averaging techniques in applications of Value-at-Risk prediction in GARCH models. Gatarek, L.T. Hoogerheide, L.F. Honing, K. http://repub.eur.nl/res/pub/39915/ 2013-10-01T00:00:00Z Response surface methodology is widely used for developing, improving, and optimizing processes in various fields. In this article, we present a method for constructing second-order rotatable designs in order to explore and optimize response surfaces based on an infinite class of supplementary difference sets. The produced designs achieve both properties of rotatability and estimation efficiency. Also, they possess good predictive properties. Koukouvinos, C. Mylona, K. Skountzou, A. Goos, P.P. http://repub.eur.nl/res/pub/39916/ 2013-09-01T00:00:00Z This paper proposes a semantic Web service discovery framework for finding semantic Web services by making use of natural language processing techniques. The framework allows searching through a set of semantic Web services in order to find a match with a user query consisting of keywords. By specifying the search goal using keywords, end-users do not need to have knowledge about semantic languages, which makes it easy to express the desired semantic Web services. For matching keywords with semantic Web service descriptions given in WSMO, techniques like part-of-speech tagging, lemmatization, and word sense disambiguation are used. After determining the senses of relevant words gathered from Web service descriptions and the user query, a matching process takes place. The performance evaluation shows that the three proposed matching algorithms are able to effectively perform matching and approximate matching. Sangers, J. Frasincar, F. Hogenboom, F.P. Chepegin, V. http://repub.eur.nl/res/pub/39604/ 2013-07-01T00:00:00Z We consider a problem of ranking alternatives based on their deterministic performance evaluations on multiple criteria. We apply additive value theory and assume the Decision Maker's (DM) preferences to be representable with general additive monotone value functions. The DM provides indirect preference information in form of pair-wise comparisons of reference alternatives, and we use this to derive the set of compatible value functions. Then, this set is analyzed to describe (1) the possible and necessary preference relations, (2) probabilities of the possible relations, (3) ranges of ranks the alternatives may obtain, and (4) the distributions of these ranks. Our work combines previous results from Robust Ordinal Regression, Extreme Ranking Analysis and Stochastic Multicriteria Acceptability Analysis under a unified decision support framework. We show how the four different results complement each other, discuss extensions of the main proposal, and demonstrate practical use of the approach by considering a problem of ranking 20 European countries in terms of 4 criteria reflecting the quality of their universities. Kadziński, M. Tervonen, T. http://repub.eur.nl/res/pub/39750/ 2013-07-01T00:00:00Z Diversity can enhance as well as disrupt team performance. Diversity beliefs and climates may play an important moderating role in these effects, but it is unclear what form these should take to promote the positive effects of diversity. Addressing this question in an integration of research in team cognition and diversity, we advance the concept of diversity mindsets, defined as team members' mental representations of team diversity. These mindsets capture diversity-related goals and associated procedural implications for goal achievement. We develop theory about the accuracy, sharedness, and awareness of sharedness of mindsets as moderators of the diversity-performance relationship. We also identify the determinants of these aspects of diversity mindsets. Finally, we discuss the implications of our model for the management of diversity. Knippenberg, D.L. van Ginkel, W.P. van Homan, A.C. http://repub.eur.nl/res/pub/39335/ 2013-06-01T00:00:00Z Park and Ride (P&R) facilities have become increasingly popular in many European metropolitan areas. Despite its popularity, however, the real impact of P&R has been criticized by many who suggest that P&R can have little or even negative effects on car use reduction. This is mainly due to the so-called unintended effects, the most familiar being the " abstraction from public transport" ; i.e., some P&R users had been making the whole trip by public transport prior the introduction of the P&R facility. This paper uses the findings of a users survey (N=738) conducted in nine rail-based P&Rs located around the cities of Rotterdam and The Hague (The Netherlands) in order to get an overview of the impacts in terms of the vehicle km travelled (VKT) and the vehicle emissions (CO2, NOx, PM10and SO2) of this popular transport infrastructure. In comparison with the existing literature, a number of additional unintended effects have been found, namely 'abstraction from bike' and 'Park and walk users' of P&R facilities, which reinforce the ambiguity surrounding the impact of P&R. Additionally, large differences have been found between the net impact of P&Rs according to their function: remote P&Rs perform better than peripheral P&Rs. This study suggests that the introduction of a fee for parking would reduce the unintended effects. Finally, it presents a number of policy suggestions. Mingardo, G. http://repub.eur.nl/res/pub/40055/ 2013-05-09T00:00:00Z Even though peer process feedback is an often used tool to enhance the effectiveness of collaborative learning environments like PBL, the conditions under which it is best facilitated still need to be investigated. Therefore, this study investigated the effects of individual versus shared reflection and goal setting on students' individual contributions to the group and their academic achievement. In addition, the influence of prior knowledge on the effectiveness of peer feedback was studied. In this pretest-intervention-posttest study 242 first year students were divided into three conditions: condition 1 (individual reflection and goal setting), condition 2 (individual and shared reflection and goal setting), and condition 3 (control group). Results indicated that the quality of individual contributions to the tutorial group did not improve after receiving the peer feedback, nor did it differ between the three conditions. With regard to academic achievement, only males in conditions 1 and 2 showed better academic achievement compared with condition 3. However, there was no difference between both ways of reflection and goal setting with regard to achievement, indicating that both ways are equally effective. Nevertheless, it is still too early to conclude that peer feedback combined with reflection and goal setting is not effective in enhancing students' individual contributions. Students only had a limited number of opportunities to improve their contributions. Therefore, future research should investigate whether an increase in number of tutorial group meetings can enhance the effectiveness of peer feedback. In addition, the effect of quality of reflection and goal setting could be taken into consideration in future research. Kamp, R.J.A. Berkel, H.J.M. van Popeijus, H.E. Leppink, J. Schmidt, H.G. Dolmans, D.H.J.M. http://repub.eur.nl/res/pub/40056/ 2013-05-09T00:00:00Z How do you respond when receiving advice from somebody with the argumentation "my gut tells me so" or "this is what my intuition says"? Most likely, you would find this justification insufficient and disregard the advice. Are there also situations where people do appreciate such intuitive advice and change their opinion accordingly? A growing number of authors write about the power of intuition in solving problems, showing that intuitively made decisions can be of higher quality than decisions based on analytical reasoning. We want to know if decision makers, when receiving advice based on an intuitive cognitive process, also recognize the value of such advice. Is advice justified by intuition necessarily followed to a lesser extent than an advice justified by analysis? Furthermore, what are the important factors influencing the effect of intuitive justification on advice taking? Participants across three studies show that utilization of intuitive advice varies depending on advisor seniority and type of task for which the advice is given. Summarizing, the results suggest that decision makers a priori doubt the value of intuitive advice and only assess it as accurate if other cues in the advice setting corroborate this. Intuitively justified advice is utilized more if it comes from a senior advisor. In decision tasks with experiential products, intuitively justified advice can even have more impact than analytically justified advice. Tzioti, S.C. Wierenga, B. Osselaer, S.M.J. van http://repub.eur.nl/res/pub/38963/ 2013-05-01T00:00:00Z For refuse collection, we estimate the cost effects of different institutional modes using panel data for almost all Dutch municipalities between 1998 and 2010. The modes we consider are private enterprises, intermunicipal cooperation, municipality-owned enterprises and in-house collection. For private companies, the cost advantage becomes substantially smaller and nonsignificant if municipal fixed effects are included. The cost advantage of intermunicipal cooperation is larger in this case than that of privatization. Dijkgraaf, E. Gradus, R.H.J.M. http://repub.eur.nl/res/pub/39336/ 2013-05-01T00:00:00Z We develop a theory of leadership that focuses on the role managers play in motivating employees through their attitudes towards employees. We model a manager's attitude as her perception about employees' abilities of successfully completing challenging tasks. We show that a positive attitude motivates employees who are driven by monetary rewards. A negative attitude may motivate employees who are driven by concerns about their reputation for being able. When employees are driven by monetary rewards and care about their reputations, an increase in the reward for successfully completing challenging tasks may lead employees to shy away from these tasks. Kamphorst, J.J.A. Swank, O.H. http://repub.eur.nl/res/pub/39755/ 2013-05-01T00:00:00Z Laser ablation U-series dating results on human and faunal bone fragments from Wajak, Indonesia, indicate a minimum age of between 37.4 and 28.5 ka (thousands of years ago) for the whole assemblage. These are significantly older than previously published radiocarbon estimates on bone carbonate, which suggested a Holocene age for a human bone fragment and a late Pleistocene age for a faunal bone. The analysis of the organic components in the faunal material show severe degradation and a positive δ13C ratio indicate a high degree of secondary carbonatisation. This may explain why the thermal release method used for the original age assessments yielded such young ages. While the older U-series ages are not in contradiction with the morphology of the Wajak human fossils or Javanese biostratigraphy, they will require a reassessment of the evolutionary relationships of modern human remains in Southeast Asia and Oceania. It can be expected that systematic direct dating of human fossils from this area will lead to further revisions of our understanding of modern human evolution. Storm, P. Wood, R. Stringer, C. Bartsiokas, A. Vos, J. de Aubert, M. Kinsley, L. Grün, R. http://repub.eur.nl/res/pub/39848/ 2013-04-19T00:00:00Z This paper develops a testing framework for comparing the predictive accuracy of copula-based multivariate density forecasts, focusing on a specific part of the joint distribution. The test is framed in the context of the Kullback-Leibler Information Criterion, but using (out-of-sample) conditional likelihood and censored likelihood in order to focus the evaluation on the region of interest. Monte Carlo simulations document that the resulting test statistics have satisfactory size and power properties in small samples. In an empirical application to daily exchange rate returns we find evidence that the dependence structure varies with the sign and magnitude of returns, such that different parametric copula models achieve superior forecasting performance in different regions of the support. Our analysis highlights the importance of allowing for lower and upper tail dependence for accurate forecasting of common extreme appreciation and depreciation of different currencies. Diks, C.G.H. Panchenko, V. Sokolinskiy, O. Dijk, D.J.C. van http://repub.eur.nl/res/pub/39954/ 2013-04-16T00:00:00Z A storm surge barrier closing of The Narrows to protect the New York and New Jersey metropolitan area from storm surges has been designed following a systematic design approach. Functions and requirements of the barrier have been determined. Important functions are retaining the storm surge, allowing ships to pass under normal conditions, and allowing sufficient tidal flow in the New York Harbor Bay. A large span of 860 ft., the Narrows is required to allow the biggest ships to pass; the sill level of this gate is 66 ft. below the mean water level. An additional 100,000 sq. ft. wet cross section is estimated to be sufficient for tidal flow. Several design options have been taken into account including sector gates, lifting gates, and flap gates. A combination of a large sliding sector gate with 18 lifting gates has been selected. The choice is based on experience with storm surge barriers in the Netherlands and combining favorable aspects of different types of barriers. Reliability and maintenance are important criteria for the selection. The location for the storm surge barrier is half a mile north of the Verrazano Bridge. This location has many advantages regarding depth of the channel, tie-in structures and length of the closure. The height of the gates is only slightly above the maximum water level of 28 ft. above mean water, allowing for wave overtopping during storm. The reduced height results in a cheaper construction. This is possible because of a large basin behind the barrier. Overtopping waves will add 2 ft. of water to the basin. Since barriers are closed early this limited rise is acceptable. The costs of the storm surge barrier are roughly estimated at US$ 6.5 billion. A significant reduction of costs is possible if the wet cross section can be reduced. This conceptual design of a storm surge barrier in the Verrazano Narrows is presented as a contribution to the debate how to deal with the increasing risks of a storm surge in New York, given the expected impact of climate change and realizing experience in the Netherlands has learned that investment in protection against floods is a good investment. Jansen, P.L.M. Dircke, P. http://repub.eur.nl/res/pub/39844/ 2013-04-12T00:00:00Z We estimate welfare losses of policies that provide on-street parking permits to residents almost free of charge in shopping districts. Our empirical results indicate that parking supply is far from perfectly price elastic, implying that there are substantial welfare losses related to under-priced parking permits. Our results suggest that the provision of residential parking permits in shopping districts induces a yearly deadweight loss of at least euro 500 per permit, which is about 30% of the supply cost of a parking place in shopping districts. Ommeren, J. van Groote, J. de Mingardo, G. http://repub.eur.nl/res/pub/39841/ 2013-04-11T00:00:00Z It is common practice to evaluate fixed-event forecast revisions in macroeconomics by regressing current forecast revisions on one-period lagged forecast revisions. Under weak-form (forecast) efficiency, the correlation between the current and one-period lagged revisions should be zero. The empirical findings in the literature suggest that this null hypothesis of zero correlation is rejected frequently, where the correlation can be either positive (which is widely interpreted in the literature as “smoothing”) or negative (which is widely interpreted as “over-reacting”). We propose a methodology to interpret such non-zero correlations in a straightforward and clear manner. Our approach is based on the assumption that numerical forecasts can be decomposed into both an econometric model and random expert intuition. We show that the interpretation of the sign of the correlation between the current and one-period lagged revisions depends on the process governing intuition, and the current and lagged correlations between intuition and news (or shocks to the numerical forecasts). It follows that the estimated non-zero correlation cannot be given a direct interpretation in terms of smoothing or over-reaction. Chang, C.L. Bruijn, B. de Franses, Ph.H.B.F. McAleer, M.J. http://repub.eur.nl/res/pub/39842/ 2013-04-11T00:00:00Z We quantify the causal effect of foreign investment on total factor productivity (TFP) using a new global firm-level database. Our identification strategy relies on exploiting the difference in the amount of foreign investment by financial and industrial investors and simultaneously controlling for unobservable firm and country-sector-year factors. Using our well identified firm level estimates for the direct effect of foreign ownership on acquired firms and for the spillover effects on domestic firms, we calculate the aggregate impact of foreign investment on country-level productivity growth and find it to be very small. Fons-Rosen, C. Kalemli-Ozcan, S. Sorensen, B.E. Villegas-Sanchez, C. http://repub.eur.nl/res/pub/39805/ 2013-04-10T00:00:00Z Complexities of dynamic volumetric imaging challenge the available computer vision techniques on a number of different fronts. This paper examines the relationship between the estimation accuracy and required amount of smoothness for a general solution from a robust statistics perspective. We show that a (surprisingly) small amount of local smoothing is required to satisfy both the necessary and sufficient conditions for accurate optic flow estimation. This notion is called 'just enough' smoothing, and its proper implementation has a profound effect on the preservation of local information in processing 3D dynamic scans. To demonstrate the effect of 'just enough' smoothing, a robust 3D optic flow method with quantized local smoothing is presented, and the effect of local smoothing on the accuracy of motion estimation in dynamic lung CT images is examined using both synthetic and real image sequences with ground truth. Bab-Hadiashar, A. Tennakoon, R.B. Bruijne, M. http://repub.eur.nl/res/pub/39816/ 2013-04-09T00:00:00Z The vision of a Smart Electric Grid relies critically on substantial advances in intelligent decentralized control mechanisms. We propose a novel class of autonomous broker agents for retail electricity trading that can operate in a wide range of Smart Electricity Markets, and that are capable of deriving long-term, profit-maximizing policies. Our brokers use Reinforcement Learning with function approximation, they can accommodate arbitrary economic signals from their environments, and they learn efficiently over the large state spaces resulting from these signals. We show how feature selection and regularization can be leveraged to automatically optimize brokers for particular market conditions, and demonstrate the performance of our design in extensive experiments using real-world energy market data. Peters, M. Ketter, W. Saar-Tsechansky, M. Collins, J.M. http://repub.eur.nl/res/pub/39817/ 2013-04-09T00:00:00Z The role of agency in overcoming path dependence and enabling sustainability transitions is receiving increasing attention. Currently lacking are more empirically derived explanations of the co-evolutionary dynamics between actors and institutional change that could potentially provide guidance on facilitating such transitions into the future. This paper investigates these dynamics through a longitudinal case analysis of Melbourne's transition to improved stormwater quality treatment. The complex data collection, analysis and validation approach, which included oral histories, semi-structured interviews, industry workshops and documentary analysis, examined the nuances of the actor-related strategies and institutional enabling processes throughout the different phases of the transition over the last fifty years. The results revealed the importance of a small group of loosely connected frontrunners from across government, private, community and scientific sectors who, through a mix of creating and disrupting institutional strategies, managed to facilitate a growing and diverse actor-network that steered this transition over decades. The establishment of networked bridging organisations was also instrumental because they formed different types of networks and alliances over time for protecting and deepening the reach of the transition dynamics across the city. The findings suggest there is no single cause-effect relationship nor one dominant intervention or action that shifted the urban stormwater management regime. Rather, it showed that the co-evolutionary processes between the broader transitional dynamics were played into by frontrunners and their actor-networks in such a way that emerging new narratives diffused, giving meaning to the evolving scientific agendas and on-the-ground experiments, which led to new institutional structures and enabling administrative tools. It seems as though each one of these dimensions is as crucial as the other in explaining the outcomes of this successful sustainability transition. Brown, R.R. Farrelly, M.A. Loorbach, D.A. http://repub.eur.nl/res/pub/39824/ 2013-04-08T00:00:00Z In general, the issue of climate change is characterized by uncertainty, complexity, and multifacetedness. In the Netherlands, climate change is in above highly controversial. These characteristics make it difficult to realize adaptation measures that are perceived as legitimate. In this article, we analyze the main difficulties and dilemmas with regard to the issue of legitimacy in the context of climate adaptation. We conceptualize legitimacy from a legal, a planning, and a network perspective and show how the concept of legitimacy evolves within these three perspectives. From a legal perspective, the focus is on the issues of good governance. From a planning perspective, the focus is on the flexibility, learning, and governance capacity. From a network perspective, issues of dialogue, involvement, and support are important. These perspectives bring in different criteria, which are not easy compatible. We describe and illustrate these legitimacy challenges using an in-depth study of the Dutch IJsseldelta Zuid case. From our case study, we conclude that, from a legitimacy perspective, the often acclaimed necessity to be adaptive and flexible is quite problematic. The same holds true for the plea to mainstream adaptation into other policy domains. In our case study, these strategies give rise to serious challenges in relation to good governance and consensus-two indispensable cornerstones of legitimacy. Buuren, M.W. van Driessen, J.P. Teisman, G.R. Rijswick, M. van