scholarly journals The infinitesimal model

2016 ◽  
Author(s):  
Nick H Barton ◽  
Alison M Etheridge ◽  
Amandine Véber

Our focus here is on the infinitesimal model. In this model, one or several quantitative traits are described as the sum of a genetic and a non-genetic component, the first being distributed as a normal random variable centred at the average of the parental genetic components, and with a variance independent of the parental traits. We first review the long history of the infinitesimal model in quantitative genetics. Then we provide a definition of the model at the phenotypic level in terms of individual trait values and relationships between individuals, but including different evolutionary processes: genetic drift, recombination, selection, mutation, population structure, ... We give a range of examples of its application to evolutionary questions related to stabilising selection, assortative mating, effective population size and response to selection, habitat preference and speciation. We provide a mathematical justification of the model as the limit as the number M of underlying loci tends to infinity of a model with Mendelian inheritance, mutation and environmental noise, when the genetic component of the trait is purely additive. We also show how the model generalises to include epistatic effects. In each case, by conditioning on the pedigree relating individuals in the population, we incorporate arbitrary selection and population structure. We suppose that we can observe the pedigree up to the present generation, together with all the ancestral traits, and we show, in particular, that the genetic components of the individual trait values in the current generation are indeed normally distributed with a variance independent of ancestral traits, up to an error of order M^{-1/2}. Simulations suggest that in particular cases the convergence may be as fast as 1/M.

Entropy ◽  
2019 ◽  
Vol 21 (1) ◽  
pp. 63 ◽  
Author(s):  
Michel Broniatowski ◽  
Jana Jurečková ◽  
Ashok Moses ◽  
Emilie Miranda

This paper focuses on test procedures under corrupted data. We assume that the observations Z i are mismeasured, due to the presence of measurement errors. Thus, instead of Z i for i = 1 , … , n, we observe X i = Z i + δ V i, with an unknown parameter δ and an unobservable random variable V i. It is assumed that the random variables Z i are i.i.d., as are the X i and the V i. The test procedure aims at deciding between two simple hyptheses pertaining to the density of the variable Z i, namely f 0 and g 0. In this setting, the density of the V i is supposed to be known. The procedure which we propose aggregates likelihood ratios for a collection of values of δ. A new definition of least-favorable hypotheses for the aggregate family of tests is presented, and a relation with the Kullback-Leibler divergence between the sets f δ δ and g δ δ is presented. Finite-sample lower bounds for the power of these tests are presented, both through analytical inequalities and through simulation under the least-favorable hypotheses. Since no optimality holds for the aggregation of likelihood ratio tests, a similar procedure is proposed, replacing the individual likelihood ratio by some divergence based test statistics. It is shown and discussed that the resulting aggregated test may perform better than the aggregate likelihood ratio procedure.


Methodology ◽  
2006 ◽  
Vol 2 (4) ◽  
pp. 142-148 ◽  
Author(s):  
Pere J. Ferrando

In the IRT person-fluctuation model, the individual trait levels fluctuate within a single test administration whereas the items have fixed locations. This article studies the relations between the person and item parameters of this model and two central properties of item and test scores: temporal stability and external validity. For temporal stability, formulas are derived for predicting and interpreting item response changes in a test-retest situation on the basis of the individual fluctuations. As for validity, formulas are derived for obtaining disattenuated estimates and for predicting changes in validity in groups with different levels of fluctuation. These latter formulas are related to previous research in the person-fit domain. The results obtained and the relations discussed are illustrated with an empirical example.


2013 ◽  
Vol 35 (2) ◽  
pp. 165-187
Author(s):  
E. S. Burt

Why does writing of the death penalty demand the first-person treatment that it also excludes? The article investigates the role played by the autobiographical subject in Derrida's The Death Penalty, Volume I, where the confessing ‘I’ doubly supplements the philosophical investigation into what Derrida sees as a trend toward the worldwide abolition of the death penalty: first, to bring out the harmonies or discrepancies between the individual subject's beliefs, anxieties, desires and interests with respect to the death penalty and the state's exercise of its sovereignty in applying it; and second, to provide a new definition of the subject as haunted, as one that has been, but is no longer, subject to the death penalty, in the light of the worldwide abolition currently underway.


1970 ◽  
Vol 6 (1) ◽  
pp. 32-42
Author(s):  
Елена Старовойтенко

Персонологическая интерпретация текстов предполагает реализацию общенаучных, а также специфических для персонологии, герменевтических установок, к которым относятся: установка на интерпретацию текста как исследование, установка на разнообразие герменевтических действий с текстом, установка на выявление неисследованных содержаний текста, установка на творческое постижение тайн текста, установка на целостное отношение к личности и "Я" автора текста, установка на выявление способности автора быть "практикующим феноменологом", установка на определение места изучаемого текста в континууме текстовых репрезентаций "личности", установка на соотнесение своего понимания текста с другими интерпретациями и их интеграцию, установка на раскрытие сущности авторской "идеи личности", возможное только в единстве интерпретаций, установка на построение и применение герменевтической модели, определяющей процедуру интерпретации как исследования и творчества, установка на определение места проделанного герменевтического поиска в культуре познания и жизни личности, установка на интерпретацию различных видов "текстов личности". Personological interpretation of texts suggests the implementation of the general scientific and also hermeneutical settings specific for Personology which include the setting of the interpretation of the text as a research, setting of a variety of hermeneutical actions with the text, setting to identify unexplored contents of the text, setting of the creative comprehension of the mysteries of the text, setting of the integrity of the attitude of the individual and the "I" of the author of the text, setting to reveal the author's ability to be "practicing phenomenologist", setting of the definition of the place in the text in the continuum of textual representations of the "personality", setting in the correlation of the understanding of the text with other interpretations and their integration, setting of the disclosure of the author's "ideas person" is possible only in the unity of interpretation, setting of the construction and usage of hermeneutical models defining the procedure for the interpretation of both studies and work, the setting to determine the place of hermeneutical research in culture and knowledge of a person's life, setting of the interpretation of various types of "texts of the individual."


2017 ◽  
Vol 1 (1) ◽  
pp. 15-31
Author(s):  
Francisco Xavier Morales

The problem of identity is an issue of contemporary society that is not only expressed in daily life concerns but also in discourses of politics and social movements. Nevertheless, the I and the needs of self-fulfillment usually are taken for granted. This paper offers thoughts regarding individual identity based on Niklas Luhmann’s systems theory. From this perspective, identity is not observed as a thing or as a subject, but rather as a “selfillusion” of a system of consciousness, which differentiates itself from the world, event after event, in a contingent way. As concerns the definition  of contents of self-identity, the structures of social systems define who is a person, how he or she should act, and how much esteem he or she should receive. These structures are adopted by consciousness as its own identity structures; however, some social contexts are more relevant for self-identity construction than others. Moral communication increases the probability that structure appropriation takes place, since the emotional element of identity is linked to the esteem/misesteem received by the individual from the interactions in which he or she participates.


Public Voices ◽  
2016 ◽  
Vol 12 (1) ◽  
pp. 67 ◽  
Author(s):  
Sharon Mastracci

In this paper, the author examines public service as depicted in the television series Buffy the Vampire Slayer (BtVS). First, she shows how slaying meets the economist’s definition of a public good, using the BtVS episode “Flooded” (6.04). Second, she discusses public service motivation (PSM) to determine whether or not Buffy, a public servant, operates from a public service ethic. Relying on established measures and evidence from shooting scripts and episode transcripts, the author concludes Buffy is a public servant motivated by a public service ethic. In this way, BtVS informs scholarship on public service by broadening the concept of PSM beyond the public sector; prompting one to wonder whether it is located in a sector, an occupation, or in the individual. These conclusions allow the author to situate Buffy alongside other idealized public servants in American popular culture.


Author(s):  
Ursula Renz

This chapter discusses the implications of Spinoza’s concept of individual bodies, as introduced in the definition of individuum in the physical digression. It begins by showing that this definition allows for an extremely wide application of the term; accordingly, very different sorts of physical entities can be described as Spinozistic individuals. Given the quite distinct use of the terms divisibilis and indivisibilis in his metaphysics, however, the chapter argues that the physical concept of individuality is not universally applied in the Ethics but reserved for physical or natural-philosophical considerations. The chapter concludes with a discussion of the problem of collective individuals. It is argued that, while societies or states are described as individual bodies, they do not constitute individual group minds in the strict sense of the term for Spinoza. This in turn indicates that minds are not individuated in the same way as bodies.


2021 ◽  
Vol 11 (1) ◽  
Author(s):  
Malin Indremo ◽  
Richard White ◽  
Thomas Frisell ◽  
Sven Cnattingius ◽  
Alkistis Skalkidou ◽  
...  

AbstractThe aim of this study was to examine the validity of the Gender Dysphoria (GD) diagnoses in the Swedish National Patient Register (NPR), to discuss different register-based definitions of GD and to investigate incidence trends. We collected data on all individuals with registered GD diagnoses between 2001 and 2016 as well as data on the coverage in the NPR. We regarded gender confirming medical intervention (GCMI) as one proxy for a clinically valid diagnosis and calculated the positive predictive value (PPV) for receiving GCMI for increasing number of registered GD diagnoses. We assessed crude and coverage-adjusted time trends of GD during 2004–2015 with a Poisson regression, using assigned sex and age as interaction terms. The PPV for receiving GCMI was 68% for ≥ 1 and 79% for ≥ 4 GD-diagnoses. The incidence of GD was on average 35% higher with the definition of ≥ 1 compared to the definition of ≥ 4 diagnoses. The incidence of GD, defined as ≥ 4 diagnoses increased significantly during the study period and mostly in the age categories 10–17 and 18–30 years, even after adjusting for register coverage. We concluded that the validity of a single ICD code denoting clinical GD in the Swedish NPR can be questioned. For future research, we propose to carefully weight the advantages and disadvantages of different register-based definitions according to the individual study’s needs, the time periods involved and the age-groups under study.


2021 ◽  
Vol 134 (5) ◽  
pp. 1343-1362
Author(s):  
Alex C. Ogbonna ◽  
Luciano Rogerio Braatz de Andrade ◽  
Lukas A. Mueller ◽  
Eder Jorge de Oliveira ◽  
Guillaume J. Bauchet

Abstract Key message Brazilian cassava diversity was characterized through population genetics and clustering approaches, highlighting contrasted genetic groups and spatial genetic differentiation. Abstract Cassava (Manihot esculenta Crantz) is a major staple root crop of the tropics, originating from the Amazonian region. In this study, 3354 cassava landraces and modern breeding lines from the Embrapa Cassava Germplasm Bank (CGB) were characterized. All individuals were subjected to genotyping-by-sequencing (GBS), identifying 27,045 single-nucleotide polymorphisms (SNPs). Identity-by-state and population structure analyses revealed a unique set of 1536 individuals and 10 distinct genetic groups with heterogeneous linkage disequilibrium (LD). On this basis, a density of 1300–4700 SNP markers were selected for large-effect quantitative trait loci (QTL) detection. Identified genetic groups were further characterized for population genetics parameters including minor allele frequency (MAF), observed heterozygosity $$({H}_{o})$$ ( H o ) , effective population size estimate $$\widehat{{(N}_{e}}$$ ( N e ^ ) and polymorphism information content (PIC). Selection footprints and introgressions of M. glaziovii were detected. Spatial population structure analysis revealed five ancestral populations related to distinct Brazilian ecoregions. Estimation of historical relationships among identified populations suggests an early population split from Amazonian to Atlantic forest and Caatinga ecoregions and active gene flows. This study provides a thorough genetic characterization of ex situ germplasm resources from cassava’s center of origin, South America, with results shedding light on Brazilian cassava characteristics and its biogeographical landscape. These findings support and facilitate the use of genetic resources in modern breeding programs including implementation of association mapping and genomic selection strategies.


2020 ◽  
Vol 30 (Supplement_5) ◽  
Author(s):  
S Svanholm ◽  
E Viitasara ◽  
H Carlerby

Abstract Background Previous research has indicated that migrants risk facing inequities both internationally and in Sweden; integration policies are therefore important to study. How health is described in policies affects how health interventions are approached. A discourse analysis offers a way of understanding how health is framed within the integration policies of the Establishment Program. The aim was to critically analyse the health discourses used in Swedish and European Union (EU) integration policies. Methods A critical discourse analysis, inspired by Fairclough, was performed on integration policies related to Sweden, on local, regional, national and the EU level. The policies of the Establishment Program, which focuses on newly arrived migrants (refugees, persons of subsidiary protection and their relatives who arrived through family reunification), were chosen for the analysis, and 17 documents were analysed in total. Results The analysis of the documents showed that although no definition of health was presented, health discourses were expressed in the form of the medicalization of health and the individualization of health. This not only by the terminology used, but also in how the healthcare sector was considered responsible for any health related issue and how individual health behaviours were of focus in interventions to promote health. Conclusions A pathogenic approach to health was visible in the policies and individual disease prevention was the main health focus. The results showed similarities to previous research highlighting how a particular understanding of health in a neoliberal context is formed. Key messages Health as a resource is missing in the integration policy documents. Viewing health as an individual quality puts the responsibility of promoting health on the individual.


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