A hierarchical zero-inflated model for species compositional data-from individual taxon responses to community response

AbstractNumerical and taxonomic resolution of compositional data sets affects investigators’ abilities to detect and measure relationships between communities and environmental factors. We test whether varying numerical (untransformed, square-root- and fourth-root-transformed relative abundance and presence–absence data) and taxonomic (species, genera, families) resolutions reveals different insights into early to middle Miocene molluscan communities along bathymetric and salinity gradients. The marine subtidal has a more even species-abundance distribution, a higher number of rare species, and higher species:family and species:genus ratios than the three habitats—marine and estuarine intertidal, estuarine subtidal—with higher fluctuations in salinity and other physical parameters. Taxonomic aggregation and numerical transformation of data result in very different ordinations, although all habitats differ significantly from one another at all taxonomic and numerical levels. Rank correlations between species-level and higher-taxon, among-sample dissimilarities are very high for proportional abundance and decrease strongly with increasing numerical transformation, most notably in the two intertidal habitats. The proportion of variation explained by depth is highest for family-level data, decreases gradually with numerical transformation, and is higher in marine than in estuarine habitats. The proportion of variation explained by salinity is highest for species-level data, increases gradually with numerical transformation, and is higher in subtidal than in intertidal habitats. Therefore, there is no single best numerical and taxonomic resolution for the discrimination of communities along environmental gradients: the “best” resolution depends on the environmental factor considered and the nature of community response to it. Different numerical and taxonomic transformations capture unique aspects of metacommunity assembly along environmental gradients that are not detectable at a single level of resolution. We suggest that simultaneous analyses of community gradients at multiple taxonomic and numerical resolutions provide novel insights into processes responsible for spatial and temporal community stability.

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Unknown and Under-Researched: The Anatomy of Drinking Under Control Programs

SUCHT - Zeitschrift für Wissenschaft und Praxis / Journal of Addiction Research and Practice ◽

10.1024/0939-5911/a000504 ◽

2017 ◽

Vol 63 (5) ◽

pp. 277-288

Author(s):

Harald Klingemann ◽

Justyna Klingemann

Keyword(s):

Quality Of Life ◽

Harm Reduction ◽

Evaluation Studies ◽

Mission Statements ◽

Community Response ◽

Limited Resources ◽

Admission Criteria ◽

Control Programs ◽

Institutional Order

Abstract. Introduction: While alcohol treatment predominantly focuses on abstinence, drug treatment objectives include a variety of outcomes related to consumption and quality of life. Consequently harm reduction programs tackling psychoactive substances are well documented and accepted by practitioners, whereas harm reduction programs tackling alcohol are under-researched and met with resistance. Method: The paper is mainly based on key-person interviews with eight program providers conducted in Switzerland in 2009 and up-dated in 2015, and the analysis of reports and mission statements to establish an inventory and description of drinking under control programs (DUCPs). A recent twin program in Amsterdam and Essen was included to exemplify conditions impeding their implementation. Firstly, a typology based on the type of alcohol management, the provided support and admission criteria is developed, complemented by a detailed description of their functioning in practice. Secondly, the case studies are analyzed in terms of factors promoting and impeding the implementation of DUCPs and efforts of legitimize them and assess their success. Results: Residential and non-residential DUCPs show high diversity and pursue individualized approaches as the detailed case descriptions exemplify. Different modalities of proactively providing and including alcohol consumption are conceptualized in a wider framework of program objectives, including among others, quality of life and harm reduction. Typically DUCPs represent an effort to achieve public or institutional order. Their implementation and success are contingent upon their location, media response, type of alcohol management and the response of other substance-oriented stake holders in the treatment system. The legitimization of DUCPs is hampered by the lack of evaluation studies. DUCPs rely mostly – also because of limited resources – on rudimentary self-evaluations and attribute little importance to data collection exercises. Conclusions: Challenges for participants are underestimated and standard evaluation methodologies tend to be incompatible with the rationale and operational objectives of DUCPs. Program-sensitive multimethod approaches enabled by sufficient financing for monitoring and accompanying research is needed to improve the practice-oriented implementation of DUCPs. Barriers for these programs include assumptions that ‘alcohol-assisted’ help abandons hope for recovery and community response to DUCPs as locally unwanted institutions (‘not in my backyard’) fuelled by stigmatization.

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