MODELING FISH LENGTH DISTRIBUTION USING A MIXTURE TECHNIQUE

In fisheries science, length and age are important aspects of fish life history. Length is a function of growth, which provides an integrated measure of the environmental and endogenous conditions, e.g. genetics, affecting individuals and populations. Length at age data can be used to assess quality and quantity of habitat, food availability, or the need for and influence of management activities. Statistical mixture techniques may be used as a means to effectively model fish length distribution. A three-component mixture model, based on normal variates, was employed to describe length distribution in mountain whitefish species. The resulting model provided parameter estimates with meaningful biological interpretations, which were in turn used for inferential and comparative purposes. The technique will be demonstrated with reference to seven years of bio-monitoring data collected from the Kootenai River in Northern Idaho prior to and post nutrient addition treatment

Welfare micropublics and inequality: urban super-diversity in a time of austerity

This article argues for the importance of the role of the national and local state, and of increasing socio-economic inequality for understanding urban super-diversity in a time of austerity. Using a methodology and conceptualisation that avoids the methodological ethnicism and ‘methodological neighbourhoodism’ inherent in some diversity research, we draw on quantitative analysis and ethnographically produced material from south London to ask what differences make a difference. Examining interactions in ‘welfare micropublics’, including maternity services, schools, and elderly social care, we show that residents and service providers, often following an ‘ethos of inclusion’, routinely engage with difference in encounters, allowing the potential for conviviality to emerge. We argue that only by considering diversity together with inequality, can we develop more textured and nuanced accounts of super-diverse urban areas, including a fuller understanding of the social production of difference and indifference