Between Psychopathology and Ideology: Challenges and Practices in Interpreting Young Extremists Experiencing Mental Illness in the Netherlands.

How violent extremism is interpreted among adolescents and young adults who experience a form of psychopathology can have far-reaching consequences for these youth and for society. A fundamental consideration here is the role that ideology and psychopathology play in radicalization and possibly related extremist violence. Risk management is challenged at various levels. This article seeks to contribute to academic and policy discussions on psychopathology and extremism by combining relevant insights from practices in the Netherlands. In this perspective article our aim is to stimulate awareness and research, on the basis of operational knowledge of the Dutch case, that helps professionals across the various domains of risk management with more expertise and the ability to better integrate and interact the concepts of psychopathology and ideology. We end with formulating hypotheses for further research.

Ecologies of ideologies: Explaining party entry and exit in West-European parliaments, 1945-2013.

This study introduces a population-ecological approach to the entry and exit of political parties. A primary proposition of population ecology is that organizational entry and exit depends on the number of organizations already present: that is, density. We propose that political parties mainly experience competition from parties in the same ideological niche (left, centre, right). Pooled time-series analyses of 410 parties, 263 elections and 18 West-European countries largely support our expectations. We find that political parties are more likely to exit when density within their niche increases. Also there is competition between adjacent ideological niches, i.e. between centrist and right-wing niches. In contrast to our expectations, neither density nor institutional rules impact party entry. This raises important questions about the rationale of prospective entrants.

Mutualism, resource competition and opposing movements among Turkish organizations in Amsterdam and Berlin, 1965-2000.

This article seeks to understand environmental effects on associational interdependencies, be they competitive or collaborative, in a polarized organizational population. To do so, it builds on the density-dependent model and the ecology of ideologies. Especially interested in the effect of context on density-dependent processes, I compare different Turkish ideological movements in Amsterdam and Berlin. Amsterdam represents an open and supportive environment for such movements, whereas Berlin constitutes a more closed and hostile one. By analysing the founding and disbanding rates of Turkish immigrant organizations in Amsterdam and Berlin during the period 1965-2000, the article demonstrates how the increasing density of Turkish ideologies has affected interdependencies in two main ways: by heightening competition, particularly between ideologically similar organizations, and by increasing counter activities between opposing movements. It also shows that the influence of context is limited. An open environment does not significantly influence the vitality rates of ideologies or further collaboration among or between them. On the contrary, it seemingly increases competition and fragmentation because more resources and opportunities are available. More signs of collaboration and mutualism are found in Berlin's closed environment.

Different effects of ethnic diversity on social capital: density of foundations and leisure associations in Amsterdam neighbourhoods.

This article examines the effect of ethnic diversity on social capital in Amsterdam neighbourhoods by looking at the effects of the ethnic diversity of a neighbourhood on the social networks that underpin civil society. A distinction is made between homogeneous, more individually oriented social networks, on the one hand, and horizontal heterogeneous networks on the other. The density of foundations­i.e. the number of foundations in a neighbourhood­is used as the indicator for the first type of networks and the density of leisure associations for the latter type. In addition, the study looks at the effect of a changing context in Amsterdam in which ethnic diversity has increasingly come to be perceived as problematic by inhabitants and local politicians. The results indeed show that ethnic diversity has a different effect on both forms of civil society: the horizontal heterogeneous networks suffer more from ethnic diversity than the homogeneous networks.