scholarly journals Multi-variate models are essential for understanding vertebrate diversification in deep time

2011 ◽  
Vol 8 (1) ◽  
pp. 127-130 ◽  
Author(s):  
Roger B. J. Benson ◽  
Philip D. Mannion
Keyword(s):  
Regression Models ◽  
Pairwise Comparisons ◽  
Sampling Effort ◽  
Weak Correlation ◽  
Complete Understanding ◽  
Bivariate Model ◽  
Deep Time ◽  
Composite Pattern ◽  
History Of ◽  
Uneven Sampling

Statistical models are helping palaeontologists to elucidate the history of biodiversity. Sampling standardization has been extensively applied to remedy the effects of uneven sampling in large datasets of fossil invertebrates. However, many vertebrate datasets are smaller, and the issue of uneven sampling has commonly been ignored, or approached using pairwise comparisons with a numerical proxy for sampling effort. Although most authors find a strong correlation between palaeodiversity and sampling proxies, weak correlation is recorded in some datasets. This has led several authors to conclude that uneven sampling does not influence our view of vertebrate macroevolution. We demonstrate that multi-variate regression models incorporating a model of underlying biological diversification, as well as a sampling proxy, fit observed sauropodomorph dinosaur palaeodiversity best. This bivariate model is a better fit than separate univariate models, and illustrates that observed palaeodiversity is a composite pattern, representing a biological signal overprinted by variation in sampling effort. Multi-variate models and other approaches that consider sampling as an essential component of palaeodiversity are central to gaining a more complete understanding of deep time vertebrate diversification.

scholarly journals A Cretaceous peak in family-level insect diversity estimated with mark–recapture methodology

2019 ◽  
Vol 286 (1917) ◽  
pp. 20192054 ◽  
Author(s):  
Sandra R. Schachat ◽  
Conrad C. Labandeira ◽  
Matthew E. Clapham ◽  
Jonathan L. Payne
Keyword(s):  
Early Cretaceous ◽  
Taxonomic Diversity ◽  
Mass Extinctions ◽  
Time Intervals ◽  
Mark Recapture ◽  
Deep Time ◽  
Steep Increase ◽  
Family Level ◽  
History Of ◽  
Uneven Sampling

The history of insects’ taxonomic diversity is poorly understood. The two most common methods for estimating taxonomic diversity in deep time yield conflicting results: the ‘range through’ method suggests a steady, nearly monotonic increase in family-level diversity, whereas ‘shareholder quorum subsampling’ suggests a highly volatile taxonomic history with family-level mass extinctions occurring repeatedly, even at the midpoints of geological periods. The only feature shared by these two diversity curves is a steep increase in standing diversity during the Early Cretaceous. This apparent diversification event occurs primarily during the Aptian, the pre-Cenozoic interval with the most described insect occurrences, raising the possibility that this feature of the diversity curves reflects preservation and sampling biases rather than insect evolution and extinction. Here, the capture–mark–recapture (CMR) approach is used to estimate insects’ family-level diversity. This method accounts for the incompleteness of the insect fossil record as well as uneven sampling among time intervals. The CMR diversity curve shows extinctions at the Permian/Triassic and Cretaceous/Palaeogene boundaries but does not contain any mass extinctions within geological periods. This curve also includes a steep increase in diversity during the Aptian, which appears not to be an artefact of sampling or preservation bias because this increase still appears when time bins are standardized by the number of occurrences they contain rather than by the amount of time that they span. The Early Cretaceous increase in family-level diversity predates the rise of angiosperms by many millions of years and can be better attributed to the diversification of parasitic and especially parasitoid insect lineages.

scholarly journals Evolutionary history of zoogeographical regions surrounding the Tibetan Plateau

2020 ◽  
Vol 3 (1) ◽  
Author(s):  
Jiekun He ◽  
Siliang Lin ◽  
Jiatang Li ◽  
Jiehua Yu ◽  
Haisheng Jiang
Keyword(s):  
Tibetan Plateau ◽  
Evolutionary History ◽  
The Tibetan Plateau ◽  
Change Over Time ◽  
Deep Time ◽  
Terrestrial Vertebrates ◽  
History Of ◽  
Striking Change ◽  
Time Periods ◽  
Over Time

AbstractThe Tibetan Plateau (TP) and surrounding regions have one of the most complex biotas on Earth. However, the evolutionary history of these regions in deep time is poorly understood. Here, we quantify the temporal changes in beta dissimilarities among zoogeographical regions during the Cenozoic using 4,966 extant terrestrial vertebrates and 1,278 extinct mammal genera. We identify ten present-day zoogeographical regions and find that they underwent a striking change over time. Specifically, the fauna on the TP was close to the Oriental realm in deep time but became more similar to the Palearctic realms more recently. The present-day zoogeographical regions generally emerged during the Miocene/Pliocene boundary (ca. 5 Ma). These results indicate that geological events such as the Indo-Asian Collision, the TP uplift, and the aridification of the Asian interior underpinned the evolutionary history of the zoogeographical regions surrounding the TP over different time periods.

The Ismaili Tradition in Iran: 13th Century to the Present

2021 ◽  
Author(s):  
Daniel Beben
Keyword(s):  
20Th Century ◽  
Future Research ◽  
Early 20Th Century ◽  
13Th Century ◽  
Complete Understanding ◽  
Northern Iran ◽  
Minority Community ◽  
History Of ◽  
The 19Th Century ◽  
To Receive

The Ismailis are a minority community of Shiʿi Muslims that first emerged in the 8th century. Iran has hosted one of the largest Ismaili communities since the earliest years of the movement and from 1095 to 1841 it served as the home of the Nizārī Ismaili imams. In 1256 the Ismaili headquarters at the fortress of Alamūt in northern Iran was captured by the Mongols and the Imam Rukn al-Dīn Khūrshāh was arrested and executed, opening a perilous new chapter in the history of the Ismailis in Iran. Generations of observers believed that the Ismailis had perished entirely in the course of the Mongol conquests. Beginning in the 19th century, research on the Ismailis began to slowly reveal the myriad ways in which they survived and even flourished in Iran and elsewhere into the post-Mongol era. However, scholarship on the Iranian Ismailis down to the early 20th century remained almost entirely dependent on non-Ismaili sources that were generally quite hostile toward their subject. The discovery of many previously unknown Ismaili texts beginning in the early 20th century offered prospects for a richer and more complete understanding of the tradition’s historical development. Yet despite this, the Ismaili tradition in the post-Mongol era continues to receive only a fraction of the scholarly attention given to earlier periods, and a number of sources produced by Ismaili communities in this period remain unexplored, offering valuable opportunities for future research.

Domestic Violence Reported to the Police: Correlates of Victims’ Reporting Behavior and Support to Legal Proceedings

2016 ◽  
Vol 31 (3) ◽  
pp. 402-415 ◽  
Author(s):  
Rémi Boivin ◽  
Chloé Leclerc
Keyword(s):  
Domestic Violence ◽  
Logistic Regression ◽  
Regression Models ◽  
Multinomial Logistic Regression ◽  
The Other ◽  
Individual Factors ◽  
Initial Report ◽  
Logistic Regression Models ◽  
Legal Proceedings ◽  
History Of

This article analyzes reported incidents of domestic violence according to the source of the complaint and whether the victim initially supported judicial action against the offender. Almost three quarters of incidents studied were reported by the victim (72%), and a little more than half of victims initially wanted to press charges (55%). Using multinomial logistic regression models, situational and individual factors are used to distinguish 4 incident profiles. Incidents in which the victim made the initial report to the police and wished to press charges are the most distinct and involve partners who were already separated at the time of the incident or had a history of domestic violence. The other profiles also show important differences.

The contribution of publications of the Yorkshire Geological Society to the understanding of the geological development of the Carboniferous Pennine Basin, northern England

2020 ◽  
Vol 63 (1) ◽  
pp. 1-32
Author(s):  
C. N. Waters ◽  
D. W. Holliday ◽  
J. I. Chisholm
Keyword(s):  
Industrial Revolution ◽  
Mineral Resources ◽  
Deep Time ◽  
The Bible ◽  
Great Insight ◽  
History Of ◽  
Sea Level Variations ◽  
Strong Control ◽  
Insight Into ◽  
Peak District

The Carboniferous rocks of the Pennine Basin form the topographical spine of the region between the Scottish Border and the Peak District. They provided many of the mineral resources that fuelled the Industrial Revolution and the growth of the great northern English cities. The description of these resources was very much a focus of early papers in the Proceedings, but they went beyond the assessment of their economic importance, providing striking early insights into our understanding of deep time when the Bible still had a strong control on scientific thinking. Over a 180 year history of publication, the Proceedings and Occasional Publications contain an unparalleled description of the rocks of the Pennine Basin of Carboniferous deposition, and they continue to provide great insight into what have been intensively studied successions but of which much still remains to be learned. This review considers the relevance of these publications to our understanding of the sedimentology of Carboniferous strata, the geometries of Carboniferous basins, how these basins constrained the formation of reefs and controlled the movement of rivers and deltas in the process of eventual infill of these basins, and how sea-level variations influenced the development of cyclical successions, the hallmark of much of the Carboniferous succession.

Bonding in Aluminum Phosphate Ceramics Prepared At Low Temperatures

1987 ◽  
Vol 114 ◽  
Author(s):  
Michael R. Silsbee ◽  
D. M. Roy
Keyword(s):  
Phosphoric Acid ◽  
Low Temperatures ◽  
Aluminum Phosphate ◽  
Complete Understanding ◽  
Chemical Binding ◽  
Binding Agents ◽  
History Of ◽  
Alumino Silicate ◽  
Characterization Studies ◽  
History Of Use

ABSTRACTPhosphates have a long history of use as binding agents in ceramic systems. In particular the phosphate bonded alumina refractories and dental cements that employ the chemical reaction between a complex alumino-silicate glass and a buffered phosphoric acid to produce binding are among the most well known.The work described here has been undertaken in an effort to achieve a more complete understanding of the nature of the chemical binding in these materials.The results of a series of characterization studies on materials from the Al2O3-P2O5-H2O and SiO2-Al2O3-P2O5-H2O systems will be discussed with particular emphasis on the nature of the binding produced in these materials.

Disagreement, Deep Time, and Progress in Philosophy

2019 ◽  
Vol 9 (4) ◽  
pp. 285-313
Author(s):  
Kirk Lougheed
Keyword(s):  
History Of Philosophy ◽  
Peer Disagreement ◽  
Epistemology Of Disagreement ◽  
Deep Time ◽  
Philosophical Beliefs ◽  
Epistemic Peer ◽  
Contingent Fact ◽  
The Future ◽  
History Of ◽  
Sceptical Conclusion

The epistemology of disagreement examines the question of how an agent ought to respond to awareness of epistemic peer disagreement about one of her beliefs. The literature on this topic, ironically enough, represents widespread disagreement about how we should respond to disagreement. I argue for the sceptical conclusion that the existence of widespread disagreement throughout the history of philosophy, and right up until the present day indicates that philosophers are highly unreliable at arriving at the truth. If truth convergence indicates progress in a field, then there is little progress in philosophy. This sceptical conclusion, however, need not make us give up philosophizing: That we should currently be sceptical of our philosophical beliefs is a contingent fact. We are an intellectually immature species and given the existence of the deep future we have some reason to think that there will be truth-convergence in philosophy in the future.

What Do We Know About Changing Economic Activity of Firms?

2019 ◽  
pp. 232102221886979
Author(s):  
Radhika Pandey ◽  
Amey Sapre ◽  
Pramod Sinha
Keyword(s):  
Economic Activity ◽  
Regression Models ◽  
Statistical Approach ◽  
Negative Binomial ◽  
Large Data ◽  
Poisson Model ◽  
Negative Binomial Regression ◽  
Data Set ◽  
Binomial Regression ◽  
History Of

Identification of primary economic activity of firms is a prerequisite for compiling several macro aggregates. In this paper, we take a statistical approach to understand the extent of changes in primary economic activity of firms over time and across different industries. We use the history of economic activity of over 46,000 firms spread over 25 years from CMIE Prowess to identify the number of times firms change the nature of their business. Using the count of changes, we estimate Poisson and Negative Binomial regression models to gain predictability over changing economic activity across industry groups. We show that a Poisson model accurately characterizes the distribution of count of changes across industries and that firms with a long history are more likely to have changed their primary economic activity over the years. Findings show that classification can be a crucial problem in a large data set like the MCA21 and can even lead to distortions in value addition estimates at the industry level. JEL Classifications: D22, E00, E01

scholarly journals Neural Networks for the Joint Development of Individual Payments and Claim Incurred

Risks ◽  
2020 ◽  
Vol 8 (2) ◽  
pp. 33
Author(s):  
Łukasz Delong ◽  
Mario V. Wüthrich
Keyword(s):  
Neural Networks ◽  
Regression Models ◽  
Development Process ◽  
Real Data ◽  
Data Set ◽  
Joint Development ◽  
Chain Ladder Method ◽  
History Of ◽  
Feature Information ◽  
Chain Ladder

The goal of this paper is to develop regression models and postulate distributions which can be used in practice to describe the joint development process of individual claim payments and claim incurred. We apply neural networks to estimate our regression models. As regressors we use the whole claim history of incremental payments and claim incurred, as well as any relevant feature information which is available to describe individual claims and their development characteristics. Our models are calibrated and tested on a real data set, and the results are benchmarked with the Chain-Ladder method. Our analysis focuses on the development of the so-called Reported But Not Settled (RBNS) claims. We show benefits of using deep neural network and the whole claim history in our prediction problem.

Principles and Methods of Zoogeography: The Field Approach

1960 ◽  
Vol 92 (8) ◽  
pp. 636-639
Author(s):  
J. Linsley Gressitt
Keyword(s):  
Field Work ◽  
Complete Understanding ◽  
Field Approach ◽  
History Of

Zoogeographic studies can be pursued in the laboratory or library, but far preferably should be largely based on careful, first-hand field work. A familiarlty with species in the field is a prerequisite to a thorough understanding of both their zoogeography and their systematics. Naturally, knowledge of the actual relationships of the species, and of the geology and geographical history of the areas involved, are also prerequisites to a complete understanding of the zoogeography of a group of insects.

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