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High Correspondence (high + correspondence)
Selected AbstractsRichness patterns, species distributions and the principle of extreme deconstructionGLOBAL ECOLOGY, Issue 2 2009Levi Carina Terribile ABSTRACT Aim, To analyse the global patterns in species richness of Viperidae snakes through the deconstruction of richness into sets of species according to their distribution models, range size, body size and phylogenetic structure, and to test if environmental drivers explaining the geographical ranges of species are similar to those explaining richness patterns, something we called the extreme deconstruction principle. Location, Global. Methods, We generated a global dataset of 228 terrestrial viperid snakes, which included geographical ranges (mapped at 1° resolution, for a grid with 7331 cells world-wide), body sizes and phylogenetic relationships among species. We used logistic regression (generalized linear model; GLM) to model species geographical ranges with five environmental predictors. Sets of species richness were also generated for large and small-bodied species, for basal and derived species and for four classes of geographical range sizes. Richness patterns were also modelled against the five environmental variables through standard ordinary least squares (OLS) multiple regressions. These subsets are replications to test if environmental factors driving species geographical ranges can be directly associated with those explaining richness patterns. Results, Around 48% of the total variance in viperid richness was explained by the environmental model, but richness sets revealed different patterns across the world. The similarity between OLS coefficients and the primacy of variables across species geographical range GLMs was equal to 0.645 when analysing all viperid snakes. Thus, in general, when an environmental predictor it is important to model species geographical ranges, this predictor is also important when modelling richness, so that the extreme deconstruction principle holds. However, replicating this correlation using subsets of species within different categories in body size, range size and phylogenetic structure gave more variable results, with correlations between GLM and OLS coefficients varying from ,0.46 up to 0.83. Despite this, there is a relatively high correspondence (r = 0.73) between the similarity of GLM-OLS coefficients and R2 values of richness models, indicating that when richness is well explained by the environment, the relative importance of environmental drivers is similar in the richness OLS and its corresponding set of GLMs. Main conclusions, The deconstruction of species richness based on macroecological traits revealed that, at least for range size and phylogenetic level, the causes underlying patterns in viperid richness differ for the various sets of species. On the other hand, our analyses of extreme deconstruction using GLM for species geographical range support the idea that, if environmental drivers determine the geographical distribution of species by establishing niche boundaries, it is expected, at least in theory, that the overlap among ranges (i.e. richness) will reveal similar effects of these environmental drivers. Richness patterns may be indeed viewed as macroecological consequences of population-level processes acting on species geographical ranges. [source] Hypothesis testing in distributed source models for EEG and MEG dataHUMAN BRAIN MAPPING, Issue 2 2006Lourens J. Waldorp Abstract Hypothesis testing in distributed source models for the electro- or magnetoencephalogram is generally performed for each voxel separately. Derived from the analysis of functional magnetic resonance imaging data, such a statistical parametric map (SPM) ignores the spatial smoothing in hypothesis testing with distributed source models. For example, when intending to test a single voxel, actually an entire region of voxels is tested simultaneously. Because there are more parameters than observations, typically constraints are employed to arrive at a solution which spatially smooths the solution. If ignored, it can be concluded from the hypothesis test that there is activity at some location where there is none. In addition, an SPM on distributed source models gives the illusion of very high resolution. As an alternative, a multivariate approach is suggested in which a region of interest is tested that is spatially smooth. In simulations with MEG and EEG it is shown that clear hypothesis testing in distributed source models is possible, provided that there is high correspondence between what is intended to be tested and what is actually tested. The approach is also illustrated by an application to data from an experiment measuring visual evoked fields when presenting checkerboard patterns. Hum Brain Mapp, 2005. © 2005 Wiley-Liss, Inc. [source] Pollen,plant,climate relationships in sub-Saharan AfricaJOURNAL OF BIOGEOGRAPHY, Issue 3 2007Julie Watrin Abstract Aim, To demonstrate that incorporating the bioclimatic range of possible contributor plants leads to improved accuracy in interpreting the palaeoclimatic record of taxonomically complex pollen types. Location, North Tropical Africa. Methods, The geographical ranges of selected African plants were extracted from the literature and geo-referenced. These plant ranges were compared with the pollen percentages obtained from a network of surface sediments. Climate-response surfaces were graphed for each pollen taxon and each corresponding plant species. Results, Several patterns can be identified, including taxa for which the pollen and plant distributions coincide, and others where the range limits diverge. Some pollen types display a reduced climate range compared with that of the corresponding plant species, due to low pollen production and/or dispersal. For other taxa, corresponding to high pollen producers such as pioneer taxa, pollen types display a larger climatic envelope than that of the corresponding plants. The number of species contained in a pollen taxon is an important factor, as the botanical species included in a taxon may have different geographical and climate distributions. Main conclusions, The comparison between pollen and plant distributions is an essential step towards more precise vegetation and climate reconstructions in Africa, as it identifies taxa that have a high correspondence between pollen and plant distribution patterns. Our method is a useful tool to reassess biome reconstructions in Africa and to characterize accurately the vegetation and climate conditions at a regional scale, from pollen data. [source] Comparing Quantitative Measures of Erythema, Pigmentation and Skin Response using ReflectometryPIGMENT CELL & MELANOMA RESEARCH, Issue 5 2002Jennifer K. Wagner We measured a number of pigmentation and skin response phenotypes in a sample of volunteers (n=397) living in State College, PA. The majority of this sample was composed of four groups based on stated ancestry: African-American, European-American, Hispanic and East Asian. Several measures of melanin concentration (L*, melanin index and adjusted melanin index) were estimated by diffuse reflectance spectroscopy and compared. The efficacy of these measures for assessing constitutive pigmentation and melanogenic dose,response was evaluated. Similarly, several measures of erythema (a*, erythema index and adjusted erythema index) were compared and evaluated in their efficacy in measuring erythema and erythemal dose,response. We show a high correspondence among all of the measures for the assessment of constitutive pigmentation and baseline erythema. However, our results demonstrate that evaluating melanogenic dose,response is highly dependent on the summary statistic used: while L* is a valid measure of constitutive pigmentation it is not an effective measure of melanogenic dose,response. Our results also confirm the use of a*, as it is shown to be highly correlated with the adjusted erythema index, a more advanced measure of erythema based on the apparent absorbance. Diffuse reflectance spectroscopy can be used to quantify the constitutive pigmentation, melanogenic dose,response at 7 d and erythemal dose,response at both 24 h and 7 d postexposure. [source] Taxonomy and structure of Croatian personality-descriptive adjectivesEUROPEAN JOURNAL OF PERSONALITY, Issue 2 2005Boris Mla This paper describes the development of a comprehensive taxonomy of Croatian personality-descriptive terms, organized in three studies. In the first study three judges searched through a standard dictionary of the Croatian language for person-descriptive terms. In the second study, personality-descriptive adjectives were classified by seven judges into 13 different categories of descriptors. In the third study, the 483 adjectives that the majority of judges in the second study classified as dispositions were rated for self-descriptions by 515 University of Zagreb students and for peer-descriptions by 513 students' best acquaintances. Self- and peer ratings were factor analysed separately and the Croatian emic lexical factors from both data sets were interpreted to be similar to the Big-Five factors: Agreeableness, Extraversion, Conscientiousness, Intellect, and Emotional Stability. The inspection of factor content of the Croatian emic factors and their relation to imported Big-Five measures revealed high correspondences for all five Croatian factors although the relation between the Croatian and the imported factors of Emotional Stability and Agreeableness was somewhat more complex. Copyright © 2004 John Wiley & Sons, Ltd. [source] | ||||||||||