scholarly journals A quantitative comparison of dispersed spore/pollen and plant megafossil assemblages from a Middle Jurassic plant bed from Yorkshire, UK

Paleobiology ◽  
2015 ◽  
Vol 41 (4) ◽  
pp. 640-660 ◽  
Author(s):  
Sam M. Slater ◽  
Charles H. Wellman
Keyword(s):  
Multivariate Analysis ◽  
Middle Jurassic ◽  
Quantitative Data ◽  
Reproductive Strategies ◽  
Quantitative Comparison ◽  
Principal Factor ◽  
Data Sets ◽  
Conflicting Evidence ◽  
Sampling Regime ◽  
Abundance And Diversity

AbstractDetailed quantitative data has previously been collected from plant megafossil assemblages from a Middle Jurassic (Aalenian) plant bed from Hasty Bank, North Yorkshire, UK. We conducted a similar analysis of palynological dispersed sporomorph (spore and pollen) assemblages collected from the same section using the same sampling regime: 67 sporomorph taxa were recorded from 50 samples taken at 10 cm intervals through the plant bed. Basic palynofacies analysis was also undertaken on each sample. Both dispersed sporomorph and plant megafossil assemblages display consistent changes in composition, diversity (richness), and abundance through time. However, the dispersed sporomorph and plant megafossil records provide conflicting evidence for the nature of parent vegetation. Specifically, conifers and ferns are underrepresented in plant megafossil assemblages, bryophytes and lycopsids are represented only in sporomorph assemblages, and sphenophytes, pteridosperms, Caytoniales, Cycadales, Ginkgoales and Bennettitales are comparatively underrepresented in sporomorph assemblages. Combined multivariate analysis (correspondence analysis and nonmetric multidimensional scaling) of sporomorph occurrence/abundance data demonstrates that temporal variation in sporomorph assemblages is the result of depositional change through the plant bed. The reproductive strategies of parent plants are considered to be a principal factor in shaping many of the major abundance and diversity irregularities between dispersed sporomorph and plant megafossil data sets that seemingly reflects different parent vegetation. Preferential occurrence/preservation of sporomorphs and equivalent parent plants is a consequence of a complex array of biological, ecological, geographical, taphonomic, and depositional factors that act inconsistently between and within fossil assemblages, which results in notable discrepancies between data sets.

Integration of Atomistic Simulation with Experiment Using Time−Temperature Superposition for a Cross-Linked Epoxy Network

2019 ◽  
Author(s):  
Ketan Khare ◽  
Frederick R. Phelan Jr.
Keyword(s):  
Master Curve ◽  
Glassy State ◽  
Superposition Principle ◽  
Quantitative Comparison ◽  
Time Shift ◽  
Data Sets ◽  
Epoxy Network ◽  
Temperature Superposition ◽  
Time Temperature Superposition ◽  
Time Temperature Superposition Principle

<a></a><a>Quantitative comparison of atomistic simulations with experiment for glass-forming materials is made difficult by the vast mismatch between computationally and experimentally accessible timescales. Recently, we presented results for an epoxy network showing that the computation of specific volume vs. temperature as a function of cooling rate in conjunction with the time–temperature superposition principle (TTSP) enables direct quantitative comparison of simulation with experiment. Here, we follow-up and present results for the translational dynamics of the same material over a temperature range from the rubbery to the glassy state. Using TTSP, we obtain results for translational dynamics out to 10<sup>9</sup> s in TTSP reduced time – a macroscopic timescale. Further, we show that the mean squared displacement (MSD) trends of the network atoms can be collapsed onto a master curve at a reference temperature. The computational master curve is compared with the experimental master curve of the creep compliance for the same network using literature data. We find that the temporal features of the two data sets can be quantitatively compared providing an integrated view relating molecular level dynamics to the macroscopic thermophysical measurement. The time-shift factors needed for the superposition also show excellent agreement with experiment further establishing the veracity of the approach</a>.

Building holistic and agile collection development and assessment

2015 ◽  
Vol 16 (1) ◽  
pp. 62-85 ◽  
Author(s):  
Cheri Jeanette Duncan ◽  
Genya Morgan O'Gara
Keyword(s):  
Quantitative Data ◽  
Holistic Approach ◽  
Assessment Model ◽  
Data Sets ◽  
Collection Development ◽  
Content Type ◽  
Qualitative And Quantitative ◽  
Institutional Goals ◽  
Scholarly Output ◽  
Use Of Data

Purpose – The purpose of this paper is to examine the development of a flexible collections assessment rubric comprised of a suite of tools for more consistently and effectively evaluating and expressing a holistic value of library collections to a variety of constituents, from administrators to faculty and students, with particular emphasis to the use of data already being collected at libraries to “take the temperature” of how responsive collections are in supporting institutional goals. Design/methodology/approach – Using a literature review, internal and external conversations, several collections pilot projects, and a variety of other investigative mechanisms, this paper explores methods for creating a more flexible, holistic collection development and assessment model using both qualitative and quantitative data. Findings – The products of scholarship that academic libraries include in their collections are expanding exponentially and range from journals and monographs in all formats, to databases, data sets, digital text and images, streaming media, visualizations and animations. Content is also being shared in new ways and on a variety of platforms. Yet the framework for evaluating this new landscape of scholarly output is in its infancy. So, how do libraries develop and assess collections in a consistent, holistic, yet agile, manner? Libraries must employ a variety of mechanisms to ensure this goal, while remaining flexible in adapting to the shifting collections environment. Originality/value – In so much as the authors are aware, this is the first paper to examine an agile, holistic approach to collections using both qualitative and quantitative data.

A Multivariate Maturity Model with a Comparative Analysis of Three Lingcod (Ophiodon elongatus) Stocks

1990 ◽  
Vol 47 (5) ◽  
pp. 948-959 ◽  
Author(s):  
Laura J. Richards ◽  
Jon T. Schnute ◽  
Claudia M. Hand
Keyword(s):  
Multivariate Analysis ◽  
Statistical Tests ◽  
Univariate Analysis ◽  
Large Data ◽  
Large Data Sets ◽  
Data Sets ◽  
Maturity Model ◽  
Age At Maturity ◽  
Ophiodon Elongatus ◽  
Special Case

In this paper we develop a multivariate analysis of length and age at maturity that includes the univariate maturity model of Schnute and Richards (1990, Can. J. Fish. Aquat. Sci. 47: 24–40) as a special case. In addition, we address the problem of drawing meaningful conclusions from large data sets oriented to fish maturity, and we present statistical tests of such conclusions. We illustrate our approach with comparisons among male and female lingcod (Ophiodon elongatus) from three stocks along the coast of British Columbia, Canada. From the univariate analysis, we demonstrate that male lingcod mature at a smaller size than female lingcod, and that for each sex, size at maturity increases with latitude. From the multivariate analysis, we determine that length and age together provide a better prediction of lingcod maturation than either variate considered alone. The multivariate model is applicable to any situation for which one or more positive variates is asymptotically related to a probability measure in the range (0, 1).

scholarly journals Multivariate analysis of the hunting tactics of Kalahari leopards

Koedoe ◽  
1997 ◽  
Vol 40 (1) ◽  
Author(s):  
J. Du P. Bothma ◽  
N. Van Rooyen ◽  
E.A.N. Le Riche
Keyword(s):  
Multivariate Analysis ◽  
Field Study ◽  
Correspondence Analysis ◽  
Detrended Correspondence Analysis ◽  
Prey Type ◽  
Data Sets ◽  
Male And Female ◽  
Sandy Substrate ◽  
Hunting Tactics

The hunting tactics of male and female leopards in the southern Kalahari were analysed for prey-specific patterns. The field study was based on tracking leopard spoor in the sandy substrate of the Kalahari. Visual profiles for each type of prey were compiled for various facets of hunting. Data sets were analysed further, using Correspondence Analysis and Detrended Correspondence Analysis. The results indicate that multivariate analysis can be used to demonstrate prey-specific hunting tactics in Kalahari leopards. In using a scarce prey base, Kalahari leopards seem to be number maximisers as they are unselective of prey type, age or sex. The presence of prey-specific hunting tactics may indicate a move along a continuum towards some degree of energy maximisation.

Comparing palynological abundance and diversity: implications for biotic replacement during the Cretaceous angiosperm radiation

Paleobiology ◽  
1999 ◽  
Vol 25 (3) ◽  
pp. 305-340 ◽  
Author(s):  
Richard Lupia ◽  
Scott Lidgard ◽  
Peter R. Crane
Keyword(s):  
Spatial Scales ◽  
Sampling Bias ◽  
Taxonomic Diversity ◽  
Detailed Examination ◽  
Northern Region ◽  
Data Sets ◽  
Floristic Diversity ◽  
Apparent Contradiction ◽  
Vegetational Change ◽  
Abundance And Diversity

The Cretaceous radiation of angiosperms initiated a major reorganization of terrestrial plant communities as dominance by pteridophytic and gymnospermic groups eventually gave way to dominance by angiosperms. Previously, patterns of biotic replacement have been assessed using measures based on taxonomic diversity data. However, using measures of both abundance and diversity to investigate replacement patterns provides more information about macroecological change in the fossil record than either can provide alone. Analyses of an updated and expanded database of North American palynological samples from Cretaceous sediments document a rapid increase in angiosperm diversity and abundance within individual fossil palynofloras (representing local/subregional vegetation). New analyses of floristic diversity patterns support previous results and indicate that the decline of free-sporing plants is more pronounced than the decline of gymnosperms. In contrast, analyses of abundance data appear to show that the decline of gymnosperms is far more pronounced than the decline of free-sporing plants. Detailed examination of both data sets segregated by paleolatitude shows that this apparent contradiction reflects biogeographical differences in the patterns of vegetational change (e.g., free-sporing plants declined in abundance at lower latitudes) as well as sampling bias (e.g., greater sampling in the northern region in the Late Cretaceous). Analyses accounting for these biases support the conclusion that as angiosperms radiated, free-sporing plants rather than gymnosperms (in this case, mainly conifers) experienced the most pronounced decline. A thorough understanding of the Cretaceous radiation of angiosperms will require both abundance and diversity data. It also will require expanding the analyses presented here into other geographic regions as well as sampling more completely at all spatial scales.

Regional Variation in the Importance and uses of Maize in the Early and Middle Formative Olmec Heartland: New Archaeobotanical Data from the San Carlos Homestead, Southern Veracruz

2012 ◽  
Vol 23 (4) ◽  
pp. 509-532 ◽  
Author(s):  
Amber M. VanDerwarker ◽  
Robert P. Kruger
Keyword(s):  
Formative Period ◽  
Quantitative Comparison ◽  
Data Sets ◽  
Power Structures ◽  
San Lorenzo ◽  
Settlement Location ◽  
La Joya ◽  
Middle Formative ◽  
San Carlos ◽  
Existing Data

AbstractThis article presents an archaeobotanical analysis from the site of San Carlos, a small Early/Middle Formative period homestead situated in the Coatzacoalcos River basin in the southern Veracruz lowlands, approximately 9 km southeast of San Lorenzo. Although archaeobotanical data from the Olmec heartland have become more widely reported in recent years, we still lack sufficient data to capture regional and temporal variation in plant foodways. Thus, we report the macrobotanical data from San Carlos and provide a quantitative comparison with existing data sets from other southern Veracruz sites with Early and Middle Formative components (La Joya and Tres Zapotes). Comparative analysis reveals that these three sites vary dramatically in terms of the ubiquity and abundance of maize, in addition to the frequencies of different fruit types. We interpret these differences in terms of (1) settlement location with respect to geographical positioning in terms of access to riverine wetlands and their resources and (2) their association with areas of developing sociopolitical power structures.

A heuristic algorithm for pattern identification in large multivariate analysis of geophysical data sets

2010 ◽  
Vol 36 (1) ◽  
pp. 83-90 ◽  
Author(s):  
João Eduardo da Silva Pereira ◽  
Adelir José Strieder ◽  
Janete Pereira Amador ◽  
José Luiz Silvério da Silva ◽  
Leônidas Luiz Volcato Descovi Filho
Keyword(s):  
Multivariate Analysis ◽  
Heuristic Algorithm ◽  
Pattern Identification ◽  
Geophysical Data ◽  
Data Sets

scholarly journals Tax Performance Assessment in Scandinavian Countries

2015 ◽  
Vol 10 (1) ◽  
pp. 47-65
Author(s):  
Liliana Bunescu
Keyword(s):  
Multivariate Analysis ◽  
Fiscal Policy ◽  
Performance Assessment ◽  
Tax Policy ◽  
Quantitative Data ◽  
Policy Performance ◽  
Fiscal Performance ◽  
Systems Model ◽  
Analysis Instrument ◽  
General Aspects

Abstract The aim of this paper is to evaluate fiscal policy performance level in Nordic countries of Europe by quantifying the gap between their performance and an optimum benchmark value. In this study it was selected Denmark, Finland, Sweden and Norway. These countries occupy the first places in the ranking of countries with the highest rate of tax burden in Europe. The first part of paper contains general aspects of fiscal performance in international research and an overview of the Nordic tax systems model. The second part of paper focuses on evaluation of tax policy performance in these countries by using OptimTax scoring analysis. The research is based on a multivariate analysis instrument that uses quantitative data on various aspects of tax policy. OptimTax achieves a score for assessing the degree of optimization of fiscal policy. The results reveal high levels of tax performance in Scandinavian countries and a trend that seems to be more constant than ascending, except Norway.

scholarly journals STRUKTUR KOMUNITAS IKAN TARGET DI TERUMBU KARANG PULAU HOGOW DAN PUTUS-PUTUS SULAWESI UTARA

2011 ◽  
Vol 7 (2) ◽  
pp. 60 ◽  
Author(s):  
Unstain NWJ Rembet ◽  
Mennofatria Boer ◽  
Dietriech G Bengen ◽  
Achmad Fahrudin
Keyword(s):  
Multivariate Analysis ◽  
Species Richness ◽  
Coral Reef ◽  
Species Diversity ◽  
Species Abundance ◽  
Controlling Factors ◽  
Ecological Groups ◽  
Species Evenness ◽  
Target Fish ◽  
Abundance And Diversity

ABSTRACTCommunity structure of target fishes was analyzed to understand their response to different conditions of coral reefs in several places of Hugow and Putus-Putus islands. This study focused on species abundance and diversity including Shannon-Wiener’s species diversity (H’), species richness (SR), species evenness (J’) and dominance (d) indices, respectively. A multivariate analysis was used for the classification or correspondence factorial analyses. The result recorded 4,501 individuals belonging to 52 species of target fishes. Both cluster and correspondence analyses clearly recognized 3 groups of target fish with 2 major controlling factors for the development of these 3 ecological groups, i.e. coral reef conditions and geographic position to the hydrodynamic condition.ABSTRAKStruktur komunitas ikan target dianalisis untuk melihat respon ikan target terhadap perbedaan kondisi terumbu karang di beberapa lokasi Pulau Hogow dan Putus-Putus. Penelitian ini dilakukan pada bulan Oktober 2010 dengan pengambilan data di 6 stasiun. Dalam penelitian ini telah dikaji variabel komunitas seperti kelimpahan dan keanekaragaman spesies termasuk indeks keanekaragaman spesies Shannon-Wiener (H’), indeks kekayaan spesies (SR), indeks kemerataan spesies (J’) dan indeks dominasi (d). Untuk melihat assemblage ikan target dilakukan analisis multivariat baik analisis klasifikasi maupun analisis faktorial koresponden. Dalam penelitian ini diperoleh 4501 indidu yang termasuk dalam 52 spesies ikan target. Analisis multivariat baik analisis cluster maupun analisis koresponden telah memisahkan dengan jelas 3 grup ikan target, dimana terdapat dua faktor utama pengendali pembentukan 3 grup ekologis ini yakni faktor kondisi terumbu karang dan faktor posisi lokasi terhadap kondisi hidrodinamika perairan.

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