Looking back at the Gifi system of nonlinear multivariate analysis

Gifi was the nom de plume for a group of researchers led by Jan de Leeuw at the University of Leiden. Between 1970 and 1990 the group produced a stream of theoretical papers and computer programs in the area of nonlinear multivariate analysis that were very innovative. In an informal way this paper discusses the so-called Gifi system of nonlinear multivariate analysis, that entails homogeneity analysis (which is closely related to multiple correspondence analysis) and generalizations. The history is discussed, giving attention to the scientific philosophy of this group, and links to machine learning are indicated

Rallying around empty signifiers: understanding and defining anti-government protest in the Netherlands

Security and Global Affair

Zijn complotdenkers psychotisch? Een vergelijking tussen complottheorieën en paranoïde wanen

Complotdenken komt veel voor in onzekere omstandigheden. Het geeft mensen houvast, zekerheid, morelesuperioriteit en sociale steun. Extreem complotdenken lijkt te passen binnen de gangbare psychiatrische definities van paranoïde wanen, maar toch zijn er ook belangrijke verschillen. Om onderscheid te kunnen maken met complotdenken behoeven gangbare definities van wanen verdieping. In plaats van de sterke focus op de foutieve inhoud van waanideeën zou er meer aandacht moeten zijn voor de onderliggende idiosyncratische, veranderde vorm van de werkelijkheidsbeleving.Security and Global Affair

Number needed to treat with ursodeoxycholic acid therapy to prevent liver transplantation or death in primary biliary cholangitis

Objective: The clinical benefit of ursodeoxycholic acid (UDCA) in primary biliary cholangitis (PBC) has never been reported in absolute measures. The aim of this study was to assess the number needed to treat (NNT) with UDCA to prevent liver transplantation (LT) or death among patients with PBC. Methods: The NNT was calculated based on the untreated LT-free survival and HR of UDCA with respect to LT or death as derived from inverse probability of treatment weighting-adjusted Cox proportional hazard analyses within the Global PBC Study Group database. Results: We included 3902 patients with a median follow-up of 7.8 (4.1-12.1) years. The overall HR of UDCA was 0.46 (95% CI 0.40 to 0.52) and the 5-year LT-free survival without UDCA was 81% (95% CI 79 to 82). The NNT to prevent one LT or death within 5 years (NNT5y) was 11 (95% CI 9 to 13). Although the HR of UDCA was similar for patients with and without cirrhosis (0.33 vs 0.31), the NNT5y was 4 (95% CI 3 to 5) and 20 (95% CI 14 to 34), respectively. Among patients with low alkaline phosphatase (ALP) (≤2× the upper limit of normal (ULN)), intermediate ALP (2-4× ULN) and high ALP (>4× ULN), the NNT5y to prevent one LT or death was 26 (95% CI 15 to 70), 11 (95% CI 8 to 17) and 5 (95% CI 4 to 8), respectively. Conclusion: The absolute clinical efficacy of UDCA with respect to LT or death varied with baseline prognostic characteristics, but was high throughout. These findings strongly emphasise the incentive to promptly initiate UDCA treatment in all patients with PBC and may improve patient compliance

Levels of alkaline phosphatase and bilirubin are surrogate end points of outcomes of patients with primary biliary cirrhosis:an international follow-up study

Noninvasive surrogate end points of long-term outcomes of patients with primary biliary cirrhosis (PBC) are needed to monitor disease progression and evaluate potential treatments. We performed a meta-analysis of individual patient data from cohort studies to evaluate whether patients' levels of alkaline phosphatase and bilirubin correlate with their outcomes and can be used as surrogate end points. We performed a meta-analysis of data from 4845 patients included in 15 North American and European long-term follow-up cohort studies. Levels of alkaline phosphatase and bilirubin were analyzed in different settings and subpopulations at different time points relative to the clinical end point (liver transplantation or death). Of the 4845 patients, 1118 reached a clinical end point. The median follow-up period was 7.3 years; 77% survived for 10 years after study enrollment. Levels of alkaline phosphatase and bilirubin measured at study enrollment (baseline) and each year for 5 years were strongly associated with clinical outcomes (lower levels were associated with longer transplant-free survival). At 1 year after study enrollment, levels of alkaline phosphatase that were 2.0 times the upper limit of normal (ULN) best predicted patient outcome (C statistic, 0.71) but not significantly better than other thresholds. Of patients with alkaline phosphatase levels ≤ 2.0 times the ULN, 84% survived for 10 years compared with 62% of those with levels >2.0 times the ULN (P 1.0 times the ULN (P < .0001). Combining levels of alkaline phosphatase and bilirubin increased the ability to predict patient survival times. We confirmed the predictive value of alkaline phosphatase and bilirubin levels in multiple subgroups, such as patients who had not received treatment with ursodeoxycholic acid, and at different time points after study enrollment. Levels of alkaline phosphatase and bilirubin can predict outcomes (liver transplantation or death) of patients with PBC and might be used as surrogate end points in therapy trial

Patterns of Lone Attackers

Lone attackers have attracted considerable attention from the media, policymakers and academics. This is partly due to the terrorist attacks Europefaced in the last couple of years executed by—seemingly—lone attackers.Academic research has explored topics like the demarcation between loneattackers and terrorist cells or networks, typologies of lone attackers, themotivation of lone attackers, and—lately—the attack patterns of lone actors.This chapter will analyse the changed understanding of lone actorviolence and discuss possible preventive approaches.Security and Global Affair

Hatred of the System: Menacing Loners and Autonomous Cells in the Netherlands

In this article, the violent threat emerging from “menacing loners” and autonomous cells in The Netherlands is being historicized and contextualized by providing quantitative and qualitative insight into this threat and illuminating some of the most dramatic incidents. Although beyond the core purpose of this mainly empirical article, some tentative remarks will be presented as possible explanation for both continuity and change. We argue that the shift from political violence originating from groups and networks to political violence perpetrated by individuals, and the shift from ideologically motivated violence to performative violence, are both shifts within a continuum, not radical breaks with the past. It is a difference in degree. Further, we argue that these gradual shifts in types of violence can only be understood as dependent on parallel manifestations of counter-policies, technological developments, and broader trends within society, rather than as attributable to indigenous terrorist developments as such. We postulate a shift from ideologically motivated to performative violence, resulting to a large extent from the possibilities offered by the Internet and social media, and from a broader cultural trend defined as the emergence of the “casting society.

Cut from the Same Cloth? Lone Actor Terrorists versus Common Homicide Offenders

The term “lone actor” has been applied to a variety of violent individuals, including jihadists, right-wing extremists, school shooters, and others whose crimes were ideologically motivated and generated much societal impact. It may be argued, however, that such a classification of this rare subset of violent offenders is an artificial one, based on political perspectives rather than on empirical findings. In this study, we examine and compare characteristics of European single perpetrators or lone actor terrorists to a large sample of European ‘common’ homicide offenders. Bivariate analysis shows that lone actors are significantly younger, more single, and more educated than homicide offenders. In terms of event characteristics, however, the two groups differ more substantially. Lone actors are more likely to attack ‘strangers’ in public places and to use firearms, while homicide offenders tend to attack victims they know in private settings and to use more hands-on methods. These differences may be understood through the notion of instrumental versus expressive motivations. Our findings question the classification of lone actors as an entity fundamentally different from our sample of single homicide offenders and call for future in-depth assessments of possible differences in homicidal drive.Security and Global Affair