Classificatory Dendrograms and Their Interpretation

1973 ◽  
Vol 21 (1) ◽  
pp. 151 ◽  
Author(s):  
HT Clifford ◽  
WT Williams
Keyword(s):  
Original Sample ◽  
Group Level ◽  
Sample Sizes ◽  
Variable Intensity ◽  
The Third ◽  
Taxonomic Groups ◽  
Base Group

The constitution and configuration of taxonomic groups resulting from applying three classificatory programs-two intensely clustering and the third of variable intensity-to two sets of data relating to a base group of 54 grass genera scored for 62 attributes are compared. All programs produced much the same groupings of genera at the 10-group level. Addition of identical taxa to the original sample resulted in increasing isolation of the replicated genus (Panicum) without affecting the composition of the remaining groups. Addition of near-identical taxa had a more generalized influence on the dendrogram. Dendrograms arrived at by intensely clustering programs may not represent taxonomically acceptable hierarchies. The flexible program causes less distortion between dendrograms based on different sample sizes, but may produce weakly structured, less informative classifications.

Two new Banksia species from pleistocene sediments in western Tasmania

1991 ◽  
Vol 4 (3) ◽  
pp. 499 ◽  
Author(s):  
GI Jordan ◽  
RS Hill
Keyword(s):  
Plant Species ◽  
Late Pleistocene ◽  
Environmental Changes ◽  
Middle Pleistocene ◽  
Extinct Species ◽  
The Third ◽  
Taxonomic Groups

Subtribe Banksiinae of the Proteaceae was diverse in Tasmania in the early and middle Tertiary, but is now restricted to two species, Banksia marginata and B. serrata. Rapid and extreme environmental changes during the Pleistocene are likely causes of the extinction of some Banksia species in Tasmania. Such extinctions may have been common in many taxonomic groups. The leaves and infructescences of Banksia kingii Jordan & Hill, sp. nov. are described from late Pleistocene sediments. This is the most recent macrofossil record of a now extinct species in Tasmania. Banksia kingii is related to the extant B. saxicola. Banksia strahanensis Jordan & Hill, sp. nov. (known only from a leaf and leaf fragments and related to B. spinulosa) is described from Early to Middle Pleistocene sediments in Tasmania. This represents the third Pleistocene macrofossil record of a plant species which is now extinct in Tasmania.

Reductions of non-pest insects in dung of cattle treated with endectocides: a comparison of four products

2002 ◽  
Vol 92 (6) ◽  
pp. 471-481 ◽  
Author(s):  
K.D. Floate ◽  
D.D. Colwell ◽  
A.S. Fox
Keyword(s):  
Adverse Effect ◽  
Cattle Dung ◽  
Apparent Discrepancy ◽  
Sample Sizes ◽  
The Third ◽  
Number Of Species ◽  
Pest Insects ◽  
Natural Assemblage ◽  
Effect Of Treatment ◽  
Post Hoc

AbstractPour-on formulations of four endectocide products were compared to assess the effect of faecal residues on insects developing in naturally-colonized dung of treated cattle. In each of three independent experiments, suppression of insects was associated with application of doramectin, eprinomectin and ivermectin, but no effect was observed for moxidectin. When data were combined across experiments to increase sample sizes, suppression of insects was observed for each compound, with the least effect being observed for moxidectin. Based on the number of species affected and duration of suppression, doramectin > ivermectin > eprinomectin ≫ moxidectin were ranked in descending order of adverse effect. A second set of three independent experiments was performed to assess the effect of endectocide treatment on dung degradation. Delayed degradation was observed for dung of cattle treated with doramectin, eprinomectin and moxidectin in the first experiment. No effect of treatment was detected in the second experiment. An effect of moxidectin was detected in the third experiment, but differences could not be detected with subsequent post-hoc tests. When data were combined across experiments to increase sample sizes, delayed degradation was detected only for eprinomectin. The apparent discrepancy between the low effect of moxidectin on insects versus its effect of dung degradation suggests the confounding action of other unidentified factors. Results of the current study indicate that use of moxidectin is least likely to affect the natural assemblage of insects associated with cattle dung.

Seed Shape Diversity in families of the Order Ranunculales

Phytotaxa ◽  
2019 ◽  
Vol 425 (4) ◽  
pp. 193-207 ◽  
Author(s):  
JOSÈ JAVIER MARTÍN-GÓMEZ ◽  
AGNIESZKA REWICZ ◽  
EMILIO CERVANTES
Keyword(s):  
Arabidopsis Thaliana ◽  
Medicago Truncatula ◽  
Life Style ◽  
Lotus Japonicus ◽  
Seed Morphology ◽  
Life Cycles ◽  
Plant Structure ◽  
Seed Shape ◽  
The Third ◽  
Taxonomic Groups

Seed shape in the order Ranunculales is described with the objective of characterizing the morphological seed types in the families of this order and to establish a correlation between seed shape, plant structure and life style.         Based on previous work in model plants (Arabidopsis thaliana, Lotus japonicus, Medicago truncatula), we have used the J index to estimate the percentage of similarity of the image of a seed with a geometric shape. The images of seeds of model plants resemble cardioid or cardioid-derived models, while seeds from other species with rapid life cycles resemble other, also simple geometrical figures. In general, seed shape may help establishing the relationships between taxonomic groups.         Three types of seed morphology are distinguished in the Ranunculales based on values of J index. In the first type, seeds in the Berberidaceae, Euptelaceae and Lardizabalaceae, adjust well to an oval. The second type, seeds in the Papaveraceae, adjust well to the cardioid model, and the third type, seeds in the Ranunculaceae, adjust well to diverse geometric shapes, including the oval, truncated cardioid, Fibonacci spiral and ellipse. In the Ranunculales, seed shape is varied and often related to geometrical figures.                The presence of cardioid derived models in the Papaveraceae supports our hypothesis that seeds resembling the cardioid are frequent in plants with rapid life cycles.Ranunculales

Communication, Consumers, and Citizens

2012 ◽  
Vol 644 (1) ◽  
pp. 6-19 ◽  
Author(s):  
Dhavan V. Shah ◽  
Lewis A. Friedland ◽  
Chris Wells ◽  
Young Mie Kim ◽  
Hernando Rojas
Keyword(s):  
Group Level ◽  
Political Consumerism ◽  
Individual Group ◽  
Fourth Section ◽  
Occupy Movement ◽  
The Third ◽  
The Individual ◽  
Future Work ◽  
Socially Situated

The year 2011 was defined by the intersection of politics and economics: the Wisconsin protests, the Occupy Movement, anti-austerity demonstrations, the Buffett Rule, and so on. These events drew attention to the role of politics in the erosion of labor power, the rise of inequality, and the excesses of overconsumption. Moving beyond periodic and dutiful action directed at an increasingly unresponsive government, citizens tested the boundaries of what we consider civic engagement by embracing personalized forms of “lifestyle politics” enacted in everyday life and often directed at the market. These issues are the focus of this volume, which we divide into four sections. The first section attempts both to situate consumption in politics as a contemporary phenomenon and to view it through a wider historical lens. The second section advances the notion of sustainable citizenship at the individual/group level and the societal/institutional level, and understands consumption as socially situated and structured. Extending this thinking, the third section explores various forms of conscious consumption and relates them to emerging modes of activism and engagement. The fourth section questions assumptions about the effectiveness of the citizen-consumer and the underlying value of political consumerism and conscious consumption. We conclude by distilling six core themes from this collection for future work.

scholarly journals Fast model-based ordination with copulas

2021 ◽  
Author(s):  
Gordana C. Popovic ◽  
Francis K.C. Hui ◽  
David I. Warton
Keyword(s):  
Latent Variables ◽  
Latent Variable ◽  
Current Model ◽  
Sample Sizes ◽  
Major Drawback ◽  
Large Sample ◽  
Model Based ◽  
Ordination Methods ◽  
Order Of Magnitude ◽  
Taxonomic Groups

Visualising data is a vital part of analysis, allowing researchers to find patterns, and assess and communicate the results of statistical modeling. In ecology, visualisation is often challenging when there are many variables (often for different species or other taxonomic groups) and they are not normally distributed (often counts or presence-absence data). Ordination is a common and powerful way to overcome this hurdle by reducing data from many response variables to just two or three, to be easily plotted. Ordination is traditionally done using dissimilarity-based methods, most commonly non-metric multidimensional scaling (nMDS). In the last decade however, model-based methods for unconstrained ordination have gained popularity. These are primarily based on latent variable models, with latent variables estimating the underlying, unobserved ecological gradients. Despite some major benefits, a major drawback of model-based ordination methods is their speed, as they typically taking much longer to return a result than dissimilarity-based methods, especially for large sample sizes. We introduce copula ordination, a new, scalable model-based approach to unconstrained ordination. This method has all the desirable properties of model-based ordination methods, with the added advantage that it is computationally far more efficient. In particular, simulations show copula ordination is an order of magnitude faster than current model-based methods, and can even be faster than nMDS for large sample sizes, while being able to produce similar ordination plots and trends as these methods.

scholarly journals Improving effect size estimation and statistical power with multi-echo fMRI and its impact on understanding the neural systems supporting mentalizing

2015 ◽  
Author(s):  
Michael V. Lombardo ◽  
Bonnie Auyeung ◽  
Rosemary J. Holt ◽  
Jack Waldman ◽  
Amber N. V. Ruigrok ◽  
...  
Keyword(s):  
Effect Size ◽  
Statistical Power ◽  
Small Sample ◽  
Cognitive Domain ◽  
Group Level ◽  
Size Estimation ◽  
Sample Sizes ◽  
Brain Organization ◽  
Effect Size Estimation ◽  
Size Estimates

AbstractFunctional magnetic resonance imaging (fMRI) research is routinely criticized for being statistically underpowered due to characteristically small sample sizes and much larger sample sizes are being increasingly recommended. Additionally, various sources of artifact inherent in fMRI data can have detrimental impact on effect size estimates and statistical power. Here we show how specific removal of non-BOLD artifacts can improve effect size estimation and statistical power in task-fMRI contexts, with particular application to the social-cognitive domain of mentalizing/theory of mind. Non-BOLD variability identification and removal is achieved in a biophysical and statistically principled manner by combining multi-echo fMRI acquisition and independent components analysis (ME-ICA). Group-level effect size estimates on two different mentalizing tasks were enhanced by ME-ICA at a median rate of 24% in regions canonically associated with mentalizing, while much more substantial boosts (40-149%) were observed in non-canonical cerebellar areas. This effect size boosting is primarily a consequence of reduction of non-BOLD noise at the subject-level, which then translates into consequent reductions in between-subject variance at the group-level. Power simulations demonstrate that enhanced effect size enables highly-powered studies at traditional sample sizes. Cerebellar effects observed after applying ME-ICA may be unobservable with conventional imaging at traditional sample sizes. Thus, ME-ICA allows for principled design-agnostic non-BOLD artifact removal that can substantially improve effect size estimates and statistical power in task-fMRI contexts. ME-ICA could help issues regarding statistical power and non-BOLD noise and enable potential for novel discovery of aspects of brain organization that are currently under-appreciated and not well understood.

Morphology and genetics concur that Anoura carishina is a synonym of Anoura latidens (Chiroptera, Glossophaginae)

Mammalia ◽  
2021 ◽  
Vol 0 (0) ◽  
Author(s):  
Camilo A. Calderón-Acevedo ◽  
Miguel E. Rodríguez-Posada ◽  
Nathan Muchhala
Keyword(s):  
Principal Components Analysis ◽  
Principal Components ◽  
Phylogenetic Analyses ◽  
Similar Species ◽  
Dental Morphology ◽  
The Third ◽  
Triangular Shape ◽  
Components Analysis ◽  
Taxonomic Groups ◽  
Anoura Geoffroyi

Abstract Anoura carishina was described based on cranial and dental morphology, but the original analyses did not include Anoura latidens, a similar species of Anoura. We used morphological, morphometric, and genetic analyses to evaluate the taxonomic identity of A. carishina. We performed a principal components analysis to evaluate the correspondence between morphological and taxonomic groups for 260 specimens of large-bodied Anoura (A. carishina, Anoura geoffroyi, A. latidens, and Anoura peruana), and statistically analyzed traits diagnostic for A. latidens, including (1) morphology of the third upper premolar (P4), (2) size of the second (P3) and third (P4) upper premolars, and (3) angle formed by the maxillary toothrows. We find that A. latidens and A. carishina are indistinguishable, and share several characters lacking in A. geoffroyi, including a P4 with triangular shape, an under-developed anterobasal cusp in the P3, a smaller braincase, and a shorter rostrum. Phylogenetic analyses using ultra-conserved elements infer that the holotype and two paratype specimens of A. carishina are paraphyletic and nested within A. latidens, while one paratype diagnosable by morphology as A. geoffroyi nests within A. geoffroyi samples. We demonstrate that A. carishina should be considered a junior synonym of A. latidens, updating the distribution of the latter.

scholarly journals Disagreement and Deliberation: Evidence from Three Deliberative Mini-Publics

2021 ◽  
Author(s):  
Kimmo Grönlund ◽  
Kaisa Herne ◽  
Kim Strandberg ◽  
Peter Söderlund
Keyword(s):  
Nuclear Power ◽  
Population Based ◽  
Experimental Manipulation ◽  
National Minority ◽  
Group Level ◽  
Individual Level ◽  
The Third ◽  
Before And After ◽  
The Individual ◽  
Citizen Deliberation

AbstractThis article is based on three experiments in citizen deliberation. We ask whether disagreement at group level as well as at individual level influence participants’ experiences of deliberation. In all three experiments, participants discussed in small groups and answered surveys before and after deliberations. The experiments were population-based with random selection. The topic of the first deliberation was nuclear power, the second dealt with immigration, and the third concerned policies for a language spoken by a national minority. The degree of group level disagreement was subject to experimental manipulation. In the first experiment, all the participants discussed in groups with mixed opinions. In the second experiment, participants were first categorized according to their baseline views, and then randomly allocated into either mixed or like-minded groups. In the third experiment, everyone discussed in like-minded groups. A trained facilitator moderated all small group discussions in the first two experiments. In the language experiment, the participants were randomly assigned into two treatments: groups with both moderation and deliberative norms, and ‘placebo’ groups. Our dependent variables consist of participants’ self-reported experiences of being heard in the discussion, and their feelings of mutual respect. The results show that all participants—regardless of group level disagreement—tend to be satisfied with deliberation. The only exception is the first experiment, where disagreement decreased process satisfaction slightly. At the individual level, participants’ deviation from the group mean had almost no effect.

scholarly journals Beyond Likert ratings: Improving the robustness of developmental research measurement using best–worst scaling

2021 ◽  
Author(s):  
Nichola Burton ◽  
Michael Burton ◽  
Carmen Fisher ◽  
Patricia González Peña ◽  
Gillian Rhodes ◽  
...  
Keyword(s):  
Best Practice ◽  
Developmentally Appropriate ◽  
Response Format ◽  
Group Level ◽  
Developmental Research ◽  
Sample Sizes ◽  
Adult Sample ◽  
Best Worst Scaling ◽  
Large Adult

AbstractSome of the ‘best practice’ approaches to ensuring reproducibility of research can be difficult to implement in the developmental and clinical domains, where sample sizes and session lengths are constrained by the practicalities of recruitment and testing. For this reason, an important area of improvement to target is the reliability of measurement. Here we demonstrate that best–worst scaling (BWS) provides a superior alternative to Likert ratings for measuring children’s subjective impressions. Seventy-three children aged 5–6 years rated the trustworthiness of faces using either Likert ratings or BWS over two sessions. Individual children’s ratings in the BWS condition were significantly more consistent from session 1 to session 2 than those in the Likert condition, a finding we also replicate with a large adult sample (N = 72). BWS also produced more reliable ratings at the group level than Likert ratings in the child sample. These findings indicate that BWS is a developmentally appropriate response format that can deliver substantial improvements in reliability of measurement, which can increase our confidence in the robustness of findings with children.

The Three Beliefs

2020 ◽  
pp. 10-16
Author(s):  
Ilana Redstone
Keyword(s):  
Sexual Orientation ◽  
Gender Identity ◽  
Free Speech ◽  
Good Thing ◽  
Group Level ◽  
The Third ◽  
Viewpoint Diversity ◽  
Race Ethnicity

Three beliefs shape much of what occurs on campuses. Taken together, these three beliefs make up a worldview that readily compromises certain values (like respect for free speech and viewpoint diversity) when they are viewed as conflicting with the goals of protecting against claims of harm. The first belief is that any action to undermine or replace traditional frameworks is by definition a good thing. The second belief is that, absent the hand of discriminatory actors, all group-level outcomes would be equal. The third belief is in the primacy of identity, which is commonly invoked through race, ethnicity, gender, religion, sexual orientation, or gender identity.

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