Showing papers by "University of Mannheim published in 2014"

Pharmacological interventions for somatoform disorders in adults.

Abstract: BACKGROUND: Somatoform disorders are characterised by chronic, medically unexplained physical symptoms (MUPS). Although different medications are part of treatment routines for people with somatoform disorders in clinics and private practices, there exists no systematic review or meta-analysis on the efficacy and tolerability of these medications. We aimed to synthesise to improve optimal treatment decisions.OBJECTIVES: To assess the effects of pharmacological interventions for somatoform disorders (specifically somatisation disorder, undifferentiated somatoform disorder, somatoform autonomic dysfunction, and pain disorder) in adults.SEARCH METHODS: We searched the Cochrane Depression, Anxiety and Neurosis Review Group's Specialised Register (CCDANCTR) (to 17 January 2014). This register includes relevant randomised controlled trials (RCTs) from The Cochrane Library (all years), MEDLINE (1950 to date), EMBASE (1974 to date), and PsycINFO (1967 to date). To identify ongoing trials, we searched ClinicalTrials.gov, Current Controlled Trials metaRegister, the World Health Organization International Clinical Trials Registry Platform, and the Chinese Clinical Trials Registry. For grey literature, we searched ProQuest Dissertation {\&} Theses Database, OpenGrey, and BIOSIS Previews. We handsearched conference proceedings and reference lists of potentially relevant papers and systematic reviews and contacted experts in the field.SELECTION CRITERIA: We selected RCTs or cluster RCTs of pharmacological interventions versus placebo, treatment as usual, another medication, or a combination of different medications for somatoform disorders in adults. We included people fulfilling standardised diagnostic criteria for somatisation disorder, undifferentiated somatoform disorder, somatoform autonomic dysfunction, or somatoform pain disorder.DATA COLLECTION AND ANALYSIS: One review author and one research assistant independently extracted data and assessed risk of bias. Primary outcomes included the severity of MUPS on a continuous measure, and acceptability of treatment.MAIN RESULTS: We included 26 RCTs (33 reports), with 2159 participants, in the review. They examined the efficacy of different types of antidepressants, the combination of an antidepressant and an antipsychotic, antipsychotics alone, or natural products (NPs). The duration of the studies ranged between two and 12 weeks.One meta-analysis of placebo-controlled studies showed no clear evidence of a significant difference between tricyclic antidepressants (TCAs) and placebo for the outcome severity of MUPS (SMD -0.13; 95{\%} CI -0.39 to 0.13; 2 studies, 239 participants; I(2) = 2{\%}; low-quality evidence). For new-generation antidepressants (NGAs), there was very low-quality evidence showing they were effective in reducing the severity of MUPS (SMD -0.91; 95{\%} CI -1.36 to -0.46; 3 studies, 243 participants; I(2) = 63{\%}). For NPs there was low-quality evidence that they were effective in reducing the severity of MUPS (SMD -0.74; 95{\%} CI -0.97 to -0.51; 2 studies, 322 participants; I(2) = 0{\%}).One meta-analysis showed no clear evidence of a difference between TCAs and NGAs for severity of MUPS (SMD -0.16; 95{\%} CI -0.55 to 0.23; 3 studies, 177 participants; I(2) = 42{\%}; low-quality evidence). There was also no difference between NGAs and other NGAs for severity of MUPS (SMD -0.16; 95{\%} CI -0.45 to 0.14; 4 studies, 182 participants; I(2) = 0{\%}).Finally, one meta-analysis comparing selective serotonin reuptake inhibitors (SSRIs) with a combination of SSRIs and antipsychotics showed low-quality evidence in favour of combined treatment for severity of MUPS (SMD 0.77; 95{\%} CI 0.32 to 1.22; 2 studies, 107 participants; I(2) = 23{\%}).Differences regarding the acceptability of the treatment (rate of all-cause drop-outs) were neither found between NGAs and placebo (RR 1.01, 95{\%} CI 0.64 to 1.61; 2 studies, 163 participants; I(2) = 0{\%}; low-quality evidence) or NPs and placebo (RR 0.85, 95{\%} CI 0.40 to 1.78; 3 studies, 506 participants; I(2) = 0{\%}; low-quality evidence); nor between TCAs and other medication (RR 1.48, 95{\%} CI 0.59 to 3.72; 8 studies, 556 participants; I(2) =14{\%}; low-quality evidence); nor between antidepressants and the combination of an antidepressant and an antipsychotic (RR 0.80, 95{\%} CI 0.25 to 2.52; 2 studies, 118 participants; I(2) = 0{\%}; low-quality evidence). Percental attrition rates due to adverse effects were high in all antidepressant treatments (0{\%} to 32{\%}), but low for NPs (0{\%} to 1.7{\%}).The risk of bias was high in many domains across studies. Seventeen trials (65.4{\%}) gave no information about random sequence generation and only two (7.7{\%}) provided information about allocation concealment. Eighteen studies (69.2{\%}) revealed a high or unclear risk in blinding participants and study personnel; 23 studies had high risk of bias relating to blinding assessors. For the comparison NGA versus placebo, there was relatively high imprecision and heterogeneity due to one outlier study. Although we identified 26 studies, each comparison only contained a few studies and small numbers of participants so the results were imprecise.AUTHORS' CONCLUSIONS: The current review found very low-quality evidence for NGAs and low-quality evidence for NPs being effective in treating somatoform symptoms in adults when compared with placebo. There was some evidence that different classes of antidepressants did not differ in efficacy; however, this was limited and of low to very low quality. These results had serious shortcomings such as the high risk of bias, strong heterogeneity in the data, and small sample sizes. Furthermore, the significant effects of antidepressant treatment have to be balanced against the relatively high rates of adverse effects. Adverse effects produced by medication can have amplifying effects on symptom perceptions, particularly in people focusing on somatic symptoms without medical causes. We can only draw conclusions about short-term efficacy of the pharmacological interventions because no trial included follow-up assessments. For each of the comparisons where there were available data on acceptability rates (NGAs versus placebo, NPs versus placebo, TCAs versus other medication, and antidepressants versus a combination of an antidepressant and an antipsychotic), no clear differences between the intervention and comparator were found.Future high-quality research should be carried out to determine the effectiveness of medications other than antidepressants, to compare antidepressants more thoroughly, and to follow-up participants over longer periods (the longest follow up was just 12 weeks). Another idea for future research would be to include other outcomes such as functional impairment or dysfunctional behaviours and cognitions as well as the classical outcomes such as symptom severity, depression, or anxiety.

Doxorubicin alone versus intensified doxorubicin plus ifosfamide for first-line treatment of advanced or metastatic soft-tissue sarcoma: a randomised controlled phase 3 trial

Abstract: Summary Background Effective targeted treatment is unavailable for most sarcomas and doxorubicin and ifosfamide—which have been used to treat soft-tissue sarcoma for more than 30 years—still have an important role Whether doxorubicin alone or the combination of doxorubicin and ifosfamide should be used routinely is still controversial We assessed whether dose intensification of doxorubicin with ifosfamide improves survival of patients with advanced soft-tissue sarcoma compared with doxorubicin alone Methods We did this phase 3 randomised controlled trial (EORTC 62012) at 38 hospitals in ten countries We included patients with locally advanced, unresectable, or metastatic high-grade soft-tissue sarcoma, age 18–60 years with a WHO performance status of 0 or 1 They were randomly assigned (1:1) by the minimisation method to either doxorubicin (75 mg/m 2 by intravenous bolus on day 1 or 72 h continuous intravenous infusion) or intensified doxorubicin (75 mg/m 2 ; 25 mg/m 2 per day, days 1–3) plus ifosfamide (10 g/m 2 over 4 days with mesna and pegfilgrastim) as first-line treatment Randomisation was stratified by centre, performance status (0 vs 1), age ( vs ≥50 years), presence of liver metastases, and histopathological grade (2 vs 3) Patients were treated every 3 weeks till progression or unacceptable toxic effects for up to six cycles The primary endpoint was overall survival in the intention-to-treat population The trial is registered with ClinicalTrialsgov, number NCT00061984 Findings Between April 30, 2003, and May 25, 2010, 228 patients were randomly assigned to receive doxorubicin and 227 to receive doxorubicin and ifosfamide Median follow-up was 56 months (IQR 31–77) in the doxorubicin only group and 59 months (36–72) in the combination group There was no significant difference in overall survival between groups (median overall survival 12·8 months [95·5% CI 10·5–14·3] in the doxorubicin group vs 14·3 months [12·5–16·5] in the doxorubicin and ifosfamide group; hazard ratio [HR] 0·83 [95·5% CI 0·67–1·03]; stratified log-rank test p=0·076) Median progression-free survival was significantly higher for the doxorubicin and ifosfamide group (7·4 months [95% CI 6·6–8·3]) than for the doxorubicin group (4·6 months [2·9–5·6]; HR 0·74 [95% CI 0·60–0·90], stratified log-rank test p=0·003) More patients in the doxorubicin and ifosfamide group than in the doxorubicin group had an overall response (60 [26%] of 227 patients vs 31 [14%] of 228; p vs 40 [18%] of 223 patients), neutropenia (93 [42%] vs 83 [37%]), febrile neutropenia (103 (46%) vs 30 [13%]), anaemia (78 [35%] vs 10 [5%]), and thrombocytopenia (75 [33%]) vs one [ Interpretation Our results do not support the use of intensified doxorubicin and ifosfamide for palliation of advanced soft-tissue sarcoma unless the specific goal is tumour shrinkage These findings should help individualise the care of patients with this disease Funding Cancer Research UK, EORTC Charitable Trust, UK NHS, Canadian Cancer Society Research Institute, Amgen

Fast Alternating Direction Optimization Methods

Abstract: Alternating direction methods are a common tool for general mathematical programming and optimization. These methods have become particularly important in the field of variational image processing, which frequently requires the minimization of nondifferentiable objectives. This paper considers accelerated (i.e., fast) variants of two common alternating direction methods: the alternating direction method of multipliers (ADMM) and the alternating minimization algorithm (AMA). The proposed acceleration is of the form first proposed by Nesterov for gradient descent methods. In the case that the objective function is strongly convex, global convergence bounds are provided for both classical and accelerated variants of the methods. Numerical examples are presented to demonstrate the superior performance of the fast methods for a wide variety of problems.

Adoption of the Linked Data Best Practices in Different Topical Domains

Abstract: The central idea of Linked Data is that data publishers support applications in discovering and integrating data by complying to a set of best practices in the areas of linking, vocabulary usage, and metadata provision. In 2011, the State of the LOD Cloud report analyzed the adoption of these best practices by linked datasets within different topical domains. The report was based on information that was provided by the dataset publishers themselves via the datahub.io Linked Data catalog. In this paper, we revisit and update the findings of the 2011 State of the LOD Cloud report based on a crawl of the Web of Linked Data conducted in April 2014. We analyze how the adoption of the different best practices has changed and present an overview of the linkage relationships between datasets in the form of an updated LOD cloud diagram, this time not based on information from dataset providers, but on data that can actually be retrieved by a Linked Data crawler. Among others, we find that the number of linked datasets has approximately doubled between 2011 and 2014, that there is increased agreement on common vocabularies for describing certain types of entities, and that provenance and license metadata is still rarely provided by the data sources.

A Conceptual Map of Political Participation

Abstract: How would you recognize a mode of participation if you see one? Owing to the rapid expansion of political activities in the last decades this question has become increasingly difficult to answer. Neither the development of all-embracing nominal definitions, nor deductive analyses of existing modes of participation seem to be helpful. In addition, the spread of expressive modes of participation makes it hard to avoid purely subjective definitions. The aim of this discussion paper is to develop an operational definition of political participation, which allows us to cover distinct conceptualizations systematically, efficiently and consistently. This goal can only be arrived at if the conventional approach of presenting nominal definitions to solve conceptual problems is left behind. Instead, available definitions are included in a set of decision rules to distinguish three main variants of political participation. A fourth variant is distinguished for non-political activities used for political purposes. Together, the four variants of political participation cover the whole range of political participation systematically without excluding any mode of political participation unknown yet. At the same time, the endless expansion of the modes of political participation in modern democracies does not result in an endless conceptual expansion. Implications for research and various examples are discussed.

Personalized task recommendation in crowdsourcing information systems - Current state of the art

Abstract: Crowdsourcing information systems are socio-technical systems that provide informational products or services by harnessing the diverse potential of large groups of people via the Web. Interested individuals can contribute to such systems by selecting among a wide range of open tasks. Arguing that current approaches are suboptimal in terms of matching tasks and contributors' individual interests and capabilities, this article advocates the introduction of personalized task recommendation mechanisms. We contribute to a conceptual foundation for the design of such mechanisms by conducting a systematic review of the corresponding academic literature. Based on the insights derived from this analysis, we identify a number of issues for future research. In particular, our findings highlight the need for more significant empirical results through large-scale online experiments, an improved dialog with mainstream recommender systems research, and the integration of various sources of knowledge that exceed the boundaries of individual systems.

The Rise of the East and the Far East: German Labor Markets and Trade Integration

Abstract: We analyze the effects of the unprecedented rise in trade between Germany and “the East” ‐ China and Eastern Europe ‐ in the period 1988‐2008 on German local labor markets. Using detailed administrative data, we exploit the cross-regional variation in initial industry structures and use trade flows of other high-income countries as instruments for regional import and export exposure. We find that the rise of “the East” in the world economy caused substantial job losses in German regions specialized in import-competing industries, both in manufacturing and beyond. Regions specialized in export-oriented industries, however, experienced even stronger employment gains and lower unemployment. In the aggregate, we estimate that this trade integration has caused some 493,000 additional jobs in the economy and contributed to retaining the manufacturing sector in Germany. We also conduct our analysis at the individual worker level, and find that trade had a stabilizing overall effect on employment relationships.

One effect to rule them all? A comment on climate and conflict

Abstract: A recent Climatic Change review article reports a remarkable convergence of scientific evidence for a link between climatic events and violent intergroup conflict, thus departing markedly from other contemporary assessments of the empirical literature. This commentary revisits the review in order to understand the discrepancy. We believe the origins of the disagreement can be traced back to the review article’s underlying quantitative meta-analysis, which suffers from shortcomings with respect to sample selection and analytical coherence. A modified assessment that addresses some of these problems suggests that scientific research on climate and conflict to date has produced mixed and inconclusive results.

Performance Impact of Middle Managers' Adaptive Strategy Implementation: the Role of Social Capital

Abstract: This article reconciles mixed findings about the performance impact of middle managers' strategy involvement. We propose that the relationship between middle managers' adaptive strategy implementation—through upward and downward influence—and objective business performance can be curvilinear and contingent on formal and informal structures. Applying a multilevel perspective to social networks, we empirically show that reputational social capital enhances the performance impact of middle managers' upward influence while informational social capital elevates the performance impact of their downward influence. The size of a business unit or region has differential moderating effects. The curvilinear effects of middle managers' upward influence and reputational and informational social capital on business unit performance reflect paradoxes. We discuss the implications of these findings for strategy implementation research and practice. Copyright © 2013 John Wiley & Sons, Ltd.

Guideline for acute therapy and management of anaphylaxis

Abstract: S2 Guideline of the German Society for Allergology and Clinical Immunology (DGAKI), the Association of German Allergologists (AeDA), the Society of Pediatric Allergy and Environmental Medicine (GPA), the German Academy of Allergology and Environmental Medicine (DAAU), the German Professional Association of Pediatricians (BVKJ), the Austrian Society for Allergology and Immunology (ÖGAI), the Swiss Society for Allergy and Immunology (SGAI), the German Society of Anaesthesiology and Intensive Care Medicine (DGAI), the German Society of Pharmacology (DGP), the German Society for Psychosomatic Medicine (DGPM), the German Working Group of Anaphylaxis Training and Education (AGATE) and the patient organization German Allergy and Asthma Association (DAAB)

Improving the Quality of Linked Data Using Statistical Distributions

Abstract: Linked Data on the Web is either created from structured data sources (such as relational databases), from semi-structured sources (such as Wikipedia), or from unstructured sources (such as text). In the latter two cases, the generated Linked Data will likely be noisy and incomplete. In this paper, we present two algorithms that exploit statistical distributions of properties and types for enhancing the quality of incomplete and noisy Linked Data sets: SDType adds missing type statements, and SDValidate identifies faulty statements. Neither of the algorithms uses external knowledge, i.e., they operate only on the data itself. We evaluate the algorithms on the DBpedia and NELL knowledge bases, showing that they are both accurate as well as scalable. Both algorithms have been used for building the DBpedia 3.9 release: With SDType, 3.4 million missing type statements have been added, while using SDValidate, 13,000 erroneous RDF statements have been removed from the knowledge base.

Comparative and qualitative robustness for law-invariant risk measures

Abstract: When estimating the risk of a P&L from historical data or Monte Carlo simulation, the robustness of the estimate is important. We argue here that Hampel’s classical notion of qualitative robustness is not suitable for risk measurement, and we propose and analyze a refined notion of robustness that applies to tail-dependent law-invariant convex risk measures on Orlicz spaces. This concept captures the tradeoff between robustness and sensitivity and can be quantified by an index of qualitative robustness. By means of this index, we can compare various risk measures, such as distortion risk measures, in regard to their degree of robustness. Our analysis also yields results of independent interest such as continuity properties and consistency of estimators for risk measures, or a Skorohod representation theorem for ψ-weak convergence.

Knowledge-based graph document modeling

Abstract: We propose a graph-based semantic model for representing document content. Our method relies on the use of a semantic network, namely the DBpedia knowledge base, for acquiring fine-grained information about entities and their semantic relations, thus resulting in a knowledge-rich document model. We demonstrate the benefits of these semantic representations in two tasks: entity ranking and computing document semantic similarity. To this end, we couple DBpedia's structure with an information-theoretic measure of concept association, based on its explicit semantic relations, and compute semantic similarity using a Graph Edit Distance based measure, which finds the optimal matching between the documents' entities using the Hungarian method. Experimental results show that our general model outperforms baselines built on top of traditional methods, and achieves a performance close to that of highly specialized methods that have been tuned to these specific tasks.

Media Makes Momentum

Abstract: Relying on 2.2 million articles from forty-five national and local U.S. newspapers between 1989 and 2010, we find that firms particularly covered by the media exhibit, ceteris paribus, significantly stronger momentum. The effect depends on article tone, reverses in the long run, is more pronounced for stocks with high uncertainty, and is stronger in states with high investor individualism. Our findings suggest that media coverage can exacerbate investor biases, leading return predictability to be strongest for firms in the spotlight of public attention. These results collectively lend credibility to an overreaction-based explanation for the momentum effect.

Firm Value Creation Through Major Channel Expansions: Evidence from an Event Study in the United States, Germany, and China.

Abstract: Although changes to the channel system are among a firm's most critical decisions, prior research has neglected to examine the impact of channel expansions on firm value. This article investigates whether a firm's announcement of an increase in distribution intensity or the establishment of a new channel influences firm value. The authors also consider the moderating role of context-specific firm, market, and channel strategy contingencies. They test their hypotheses with an event study of 240 announcements of major channel expansions in the United States, Germany, and China. The results indicate that channel expansions affect firm value (i.e., through abnormal stock returns). However, the two types of channel expansions affect firm value differently. Whereas the establishment of a new channel positively influences firm value, reactions to an increase in distribution intensity are highly contingent. For example, firms operating in exceedingly turbulent or competitive markets experience firm value reductio...

Outsourced Proofs of Retrievability

Abstract: Proofs of Retrievability (POR) are cryptographic proofs that enable a cloud provider to prove that a user can retrieve his file in its entirety. POR need to be frequently executed by the user to ensure that their files stored on the cloud can be fully retrieved at any point in time. To conduct and verify POR, users need to be equipped with devices that have network access, and that can tolerate the (non-negligible) computational overhead incurred by the verification process. This clearly hinders the large-scale adoption of POR by cloud users, since many users increasingly rely on portable devices that have limited computational capacity, or might not always have network access. In this paper, we introduce the notion of outsourced proofs of retrievability (OPOR), in which users can task an external auditor to perform and verify POR with the cloud provider. We argue that the OPOR setting is subject to security risks that have not been covered by existing POR security models. To remedy that, we propose a formal framework and a security model for OPOR. We then propose an instantiation of OPOR which builds upon the provably-secure private POR scheme due to Shacham and Waters (Asiacrypt'08) and we show its security in our proposed security model. We implement a prototype based on our solution, and evaluate its performance in a realistic cloud setting. Our evaluation results show that our proposal minimizes user effort, incurs negligible overhead on the auditor (compared to the SW scheme), and considerably improves over existing publicly verifiable POR.

Controlling the stream of thought: working memory capacity predicts adjustment of mind-wandering to situational demands.

Abstract: Although engaging in task-unrelated thoughts can be enjoyable and functional under certain circumstances, allowing one's mind to wander off-task will come at a cost to performance in many situations. Given that task-unrelated thoughts need to be blocked out when the current task requires full attention, it has been argued that cognitive control is necessary to prevent mind-wandering from becoming maladaptive. Extending this idea, we exposed participants to tasks of different demands and assessed mind-wandering via thought probes. Employing a latent-change model, we found mind-wandering to be adjusted to current task demands. As hypothesized, the degree of adjustment was predicted by working memory capacity, indicating that participants with higher working memory capacity were more flexible in their coordination of on- and off-task thoughts. Notably, the better the adjustment, the smaller performance decrements due to increased task demands were. On the basis of these findings, we argue that cognitive control does not simply allow blocking out task-unrelated thoughts but, rather, allows one to flexibly adjust mind-wandering to situational demands.

Who Takes the Parliamentary Floor? The Role of Gender in Speech-making in the Swedish Riksdag

Abstract: Legislative speeches are an important instrument for parties and members of parliament (MPs) to signal their positions and priorities. This raises the question of who speaks when. We evaluate whether a MP’s presence on the floor depends on his or her gender. We hypothesize that female MPs give in general less speeches in parliament and that this pattern results from debates dealing with “harder” policy issues. Our expectations are supported when analyzing a new data set containing information on the number and content of speeches given in the Swedish Riksdag between 2002 and 2010.

Monitoring job offer decisions, punishments, exit to work, and job quality

Abstract: Unemployment insurance systems include the monitoring of unemployed workers and punitive sanctions if job search requirements are violated. We analyze the causal effect of sanctions on the ensuing job quality, notably on wages and occupational level. We use Swedish data and estimate duration models dealing with selection on unobservables. We also develop a theoretical job search model that monitors job offer rejection versus job search effort. The empirical results show that, after a sanction, the wage rate is lower and individuals move more often to a part-time job and a lower occupational level, incurring human capital losses.

Firm-hosted online brand communities and new product success

Abstract: Many firms use online brand communities to support the launch of their new products. This study proposes a typology of firm-hosted online brand communities and examines whether such a classification system can improve predictions of new product success. A cross-industry analysis of 81 firm-hosted online brand communities shows that these communities reflect three archetypes. A subsequent survey of 170 community-hosting firms in the consumer durable goods industry reveals that the three types of communities are not equally important for new product success. Moreover, one archetype generally underperforms the other two as a new product support mechanism. Overall, the results demonstrate that firm-hosted online brand communities can be a predictor of new product success.

Entertainment 2.0? The Role of Intrinsic and Extrinsic Need Satisfaction for the Enjoyment of Facebook Use

Abstract: While intrinsic motivation has received broad attention in recent entertainment research, the effects of extrinsic motivation, such as social pressure to use media, on media enjoyment remain unknown. Based on an online-survey (N = 230), this study tested the effects of intrinsic need satisfaction and perceived social pressure on the enjoyment of Facebook use with structural equation modeling. The results reveal complex effects of extrinsic motivation: While social pressure negatively affected autonomy need satisfaction, it was positively related to competence and relatedness need satisfaction. This study is the first to develop and test a theoretical model of entertainment experience in the context of social media use and to theoretically integrate the role of extrinsic need satisfaction in media enjoyment.

Exercise after work, psychological mediators, and affect: A day-level study.

Abstract: In this diary study, we tested the recovery potential of exercise activities during leisure time and examined the psychological mechanisms underlying the relation between exercise activities and affect. We hypothesized that spending time on exercise activities after work will be related to subsequent affect in the evening, and that psychological detachment from work, sense of belonging, and physical self-perceptions explain why exercise activities are related to subsequent affect. One-hundred and twenty-six participants from diverse occupations completed a diary twice a day over five consecutive work days. Multilevel analyses showed that exercise activities after work were related to positive, but not to negative affect in the evening. As proposed, psychological detachment, sense of belonging, and physical self-perceptions mediated the relation between exercise activities after work and positive affect in the evening.

Dealignment, De-legitimation and the Implosion of the Two-Party System in Greece: The Earthquake Election of 6 May 2012

Abstract: This article examines the political effects of the global economic recession on Greece in the period from 2010 up to the last weeks of the campaign period for the national elections of 6 May 2012. Our objectives are threefold. First we seek to contextualize its impact and show how the Greek party system departed from the nearly three decades of stability after 2009 and entered a period electoral fluidity and dealignment. Second we identify the demographic and structural characteristics of that dealignment process. Finally we interpret and compare the effect of the economic crisis and other issues on vote choice in the 2012 general election.

The WebDataCommons Microdata, RDFa and Microformat Dataset Series

Abstract: In order to support web applications to understand the content of HTML pages an increasing number of websites have started to annotate structured data within their pages using markup formats such as Microdata, RDFa, Microformats The annotations are used by Google, Yahoo!, Yandex, Bing and Facebook to enrich search results and to display entity descriptions within their applications In this paper, we present a series of publicly accessible Microdata, RDFa, Microformats datasets that we have extracted from three large web corpora dating from 2010, 2012 and 2013 Altogether, the datasets consist of almost 30 billion RDF quads The most recent of the datasets contains amongst other data over 211 million product descriptions, 54 million reviews and 125 million postal addresses originating from thousands of websites The availability of the datasets lays the foundation for further research on integrating and cleansing the data as well as for exploring its utility within different application contexts As the dataset series covers four years, it can also be used to analyze the evolution of the adoption of the markup formats

Graph structure in the web --- revisited: a trick of the heavy tail

Abstract: Knowledge about the general graph structure of the World Wide Web is important for understanding the social mechanisms that govern its growth, for designing ranking methods, for devising better crawling algorithms, and for creating accurate models of its structure. In this paper, we describe and analyse a large, publicly accessible crawl of the web that was gathered by the Common Crawl Foundation in 2012 and that contains over 3.5 billion web pages and 128.7 billion links. This crawl makes it possible to observe the evolution of the underlying structure of the World Wide Web within the last 10 years: we analyse and compare, among other features, degree distributions, connectivity, average distances, and the structure of weakly/strongly connected components. Our analysis shows that, as evidenced by previous research, some of the features previously observed by Broder et al. are very dependent on artefacts of the crawling process, whereas other appear to be more structural. We confirm the existence of a giant strongly connected component; we however find, as observed by other researchers, very different proportions of nodes that can reach or that can be reached from the giant component, suggesting that the "bow-tie structure" is strongly dependent on the crawling process, and to the best of our current knowledge is not a structural property of the web. More importantly, statistical testing and visual inspection of size-rank plots show that the distributions of indegree, outdegree and sizes of strongly connected components are not power laws, contrarily to what was previously reported for much smaller crawls, although they might be heavy-tailed. We also provide for the first time accurate measurement of distance-based features, using recently introduced algorithms that scale to the size of our crawl.

How Context Matters? Mobilization, Political Opportunity Structures, and Nonelectoral Political Participation in Old and New Democracies:

Abstract: Scholars have long argued that political participation is determined by institutional context. Within the voter turnout literature, the impact of various institutional structures has been demonstrated in numerous studies. Curiously, a similar context-driven research agenda exploring the correlates of nonelectoral participation (NEP) has not received the same attention. This study addresses this lacuna by testing a political opportunity structure (POS) model of citizen activism across 24 old and new democracies using International Social Survey Programme 2004: Citizenship (ISSP 2004) data. Using a multilevel modeling approach, this study tests a competition versus consensus conception of how decentralized institutions determine NEP. This research demonstrates that states with more competitive veto points operating through systems of horizontal and territorial decentralization increase individual NEP. In addition, it interacts with social mobilization networks to promote greater citizen activism: Institutio...

Exhaustion and lack of psychological detachment from work during off-job time: moderator effects of time pressure and leisure experiences.

Abstract: Lack of psychological detachment from work during off-job time contributes to the increase in employee exhaustion over time. This study examines the reverse causal path from exhaustion to lack of psychological detachment, suggesting that this reverse process may operate within a relatively short time frame. Specifically, we examine if exhaustion predicts a decrease in psychological detachment from work during off-job time within several weeks. We propose that time pressure at work intensifies and that pleasurable leisure experiences reduce this association between exhaustion and the decrease in psychological detachment. We tested our hypotheses in a short-term prospective study (time lag: 4 weeks) with a sample of 109 employees. Ordinary least square regression analysis indicates that exhaustion predicted a decrease in psychological detachment from work over the course of 4 weeks. This decrease was particularly strong for employees working under time pressure and for employees who did not engage in pleasurable leisure experiences. Our findings suggest that exhausted employees find detachment from work increasingly difficult and therefore might suffer from insufficient recovery-although they need it most. The situation is particularly severe when exhausted employees face high time pressure and a lack of pleasurable leisure experiences.