Perception of the Similarity Structure of Objects:  A Stratified Model

Abstract Background Prognostic models developed in general cohorts with a mixture of heart failure (HF) phenotypes, though more widely applicable, are also likely to yield larger prediction errors in settings where the HF phenotypes have substantially different baseline mortality rates or different predictor-outcome associations. This study sought to use individual participant data meta-analysis to develop an HF phenotype stratified model for predicting 1-year mortality in patients admitted with acute HF. Methods Four prospective European cohorts were used to develop an HF phenotype stratified model. Cox model with two rounds of backward elimination was used to derive the prognostic index. Weibull model was used to obtain the baseline hazard functions. The internal-external cross-validation (IECV) approach was used to evaluate the generalizability of the developed model in terms of discrimination and calibration. Results 3577 acute HF patients were included, of which 2368 were classified as having HF with reduced ejection fraction (EF) (HFrEF; EF < 40%), 588 as having HF with midrange EF (HFmrEF; EF 40–49%), and 621 as having HF with preserved EF (HFpEF; EF ≥ 50%). A total of 11 readily available variables built up the prognostic index. For four of these predictor variables, namely systolic blood pressure, serum creatinine, myocardial infarction, and diabetes, the effect differed across the three HF phenotypes. With a weighted IECV-adjusted AUC of 0.79 (0.74–0.83) for HFrEF, 0.74 (0.70–0.79) for HFmrEF, and 0.74 (0.71–0.77) for HFpEF, the model showed excellent discrimination. Moreover, there was a good agreement between the average observed and predicted 1-year mortality risks, especially after recalibration of the baseline mortality risks. Conclusions Our HF phenotype stratified model showed excellent generalizability across four European cohorts and may provide a useful tool in HF phenotype-specific clinical decision-making.

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Jewish Perceptions of Antisemitism in the European Union, 2018: A New Structural Look

Analysis of Current Trends in Antisemitism - ACTA ◽

10.1515/actap-2020-2001 ◽

2020 ◽

Vol 40 (2) ◽

Author(s):

Sergio DellaPergola

Keyword(s):

European Union ◽

Research Literature ◽

The European Union ◽

Research Issues ◽

Similarity Structure ◽

Methodological Problems ◽

Prejudice And Discrimination ◽

Anti Jewish ◽

The Eu

AbstractThis paper aims at providing a new systemic contribution to research about perceptions of antisemitism/Judeophobia by contemporary Jews in 12 European Union countries. The perspective – the viewpoint of the offended side – has been less prominent relatively in research literature on antisemitism. The data analysis demonstrates the potential power of Similarity Structure Analysis (SSA) as a better theoretical and empirical tool to describe and conceptualize the contents of chosen research issues. After a brief review of some methodological problems in the study of antisemitism, this paper will re-elaborate data first published in the report of the 2018 FRA study Experiences and Perceptions of Antisemitism – Second survey on Discrimination and Hate Crimes against Jews in the EU (FRA 2018a). Topics include the perceived importance of antisemitism as a societal issue, the contents of anti-Jewish prejudice and discrimination, channels of transmission, perpetrators of offenses, regional differences within Europe, and the role of antisemitism perceptions as a component of Jewish identification. Special attention is paid to the distinction between cognitive and experiential perceptions of antisemitism, and to the typology of practical, populist, political, and narrative antisemitism.

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Cognitive Information Systems for Protection of Museum Complexes

International Journal of Engineering & Technology ◽

10.14419/ijet.v7i4.38.24326 ◽

2018 ◽

Vol 7 (4.38) ◽

pp. 82

Author(s):

Aleksey Valentinovich Bogdanov ◽

Igor Gennadievich Malygin

Keyword(s):

Artificial Intelligence ◽

Information Systems ◽

Information Security ◽

Security System ◽

Structural Scheme ◽

Cognitive Information ◽

Technological Platform ◽

Network Technologies ◽

Cognitive Information Systems ◽

Stratified Model

The paper considers the conceptual provisions of building a promising cognitive information security system of the museum complex on a cyber-physical basis. The stratified model of cognitive information security system of the museum complex was presented. It was shown that the key technological platform for the security of the museum complex is information and network technologies integrated (converged) with the technologies of industrial artificial intelligence. The generalized structural scheme of the cognitive cycle of the information security system of the museum complex was considered. The characteristic of the basic processes realized in a cognitive contour was given.

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Scale-dependent merging of baroclinic vortices

Journal of Fluid Mechanics ◽

10.1017/s0022112094000595 ◽

1994 ◽

Vol 264 ◽

pp. 81-106 ◽

Cited By ~ 21

Author(s):

J. Verron ◽

S. Valcke

Keyword(s):

Numerical Simulations ◽

Critical Point ◽

Lower Layer ◽

Interaction Mechanism ◽

Competitive Effects ◽

Different Types ◽

Shape Effects ◽

Baroclinic Vortices ◽

The Relationship ◽

Stratified Model

The influence of stratification on the merging of like-sign vortices of equal intensity and shape is investigated by numerical simulations in a quasi-geostrophic, two-layer stratified model. Two different types of vortices are considered: vortices defined as circular patches of uniform potential vorticity in the upper layer but no PV anomaly in the lower layer (referred to as PVI vortices), and vortices defined as circular patches of uniform relative vorticity in the upper layer but no motion in the lower layer (referred to as RVI vortices). In particular, it is found that, in the RVI case, the merging behaviour depends strongly on the magnitude of the stratification (i.e. the ratio of internal Rossby radius and vortex radius). The critical point here appears to be whether or not the initial eddies have a deep flow signature in terms of PV.The specific phenomenon of scale-dependent merging observed is interpreted in terms of the competitive effects of hetonic interaction and vortex shape. In the case of weaker stratification, the baroclinic structure of the eddies can be seen as dominated by a mechanism of hetonic interaction in which bottom flow appears to counteract the tendency of surface eddies to merge. In the case of larger stratification, the eddy interaction mechanism is shown to be barotropically dominated, although interface deformation still determines the actual eddy vorticity profile during the initialization stage. Repulsion (hetonic) effect therefore oppose attraction (barotropic shape) effects in a competitive process dependent on the relationship between the original eddy lengthscale and the first internal Rossby radius.A concluding discussion considers the implications of such analysis for real situations, in the ocean or in the laboratory.

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Rote learning as a function of similarity structure and task sequence.

Journal of Experimental Psychology ◽

10.1037/h0024097 ◽

1967 ◽

Vol 73 (2) ◽

pp. 292-297 ◽

Cited By ~ 1

Author(s):

Newton C. Ellis ◽

Winton H. Manning

Keyword(s):

Rote Learning ◽

Task Sequence ◽

Similarity Structure ◽

And Task

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Decoding the Information Structure Underlying the Neural Representation of Concepts

10.1101/2021.03.16.435524 ◽

2021 ◽

Author(s):

Leonardo Fernandino ◽

Lisa L. Conant ◽

Colin J. Humphries ◽

Jeffrey R. Binder

Keyword(s):

Information Structure ◽

Conceptual Knowledge ◽

Neural Representation ◽

Neural Activation ◽

Activation Patterns ◽

Concept Representation ◽

Native Space ◽

Distributional Information ◽

Similarity Structure ◽

Types Of Information

The nature of the neural code underlying conceptual knowledge remains a major unsolved problem in cognitive neuroscience. Three main types of information have been proposed as candidates for the neural representations of lexical concepts: taxonomic (i.e., information about category membership and inter-category relations), distributional (i.e., information about patterns of word co-occurrence in natural language use), and experiential (i.e., information about sensory-motor, affective, and other features of phenomenal experience engaged during concept acquisition). In two experiments, we investigated the extent to which these three types of information are encoded in the neural activation patterns associated with hundreds of English nouns from a wide variety of conceptual categories. Participants made familiarity judgments on the meaning of written nouns while undergoing functional MRI. A high-resolution, whole-brain activation map was generated for each noun in each participant′s native space. These word-specific activation maps were used to evaluate different representational spaces corresponding to the three types of information described above. In both studies, we found a striking advantage for experience-based models in most brain areas previously associated with concept representation. Partial correlation analyses revealed that only experiential information successfully predicted concept similarity structure when inter-model correlations were taken into account. This pattern of results was found independently for object concepts and event concepts. Our findings indicate that the neural representation of conceptual knowledge primarily encodes information about features of experience, and that - to the extent that it is represented in the brain - taxonomic and distributional information may rely on such an experience-based code.

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Models of Multiple Events in the Analysis of Subsequent Registrations in the Labour Office

Acta Universitatis Lodziensis Folia oeconomica ◽

10.18778/0208-6018.348.07 ◽

2020 ◽

Vol 3 (348) ◽

pp. 131-147

Author(s):

Beata Bieszk-Stolorz

Keyword(s):

Recurrent Events ◽

Medical Science ◽

Disease Recurrence ◽

Time Frame ◽

Proportional Hazard ◽

Cox Proportional Hazard ◽

Conditional Models ◽

The Unemployed ◽

The Impact ◽

Stratified Model

In many fields of science, it is necessary to analyse recurrent events. In medical science, the problem is to assess the risk of chronic disease recurrence. In economic and social sciences, it is possible to analyse the time of entering and leaving the sphere of poverty, the time of subsequent guarantee or insurance claims, as well as the time of subsequent periods of unemployment. In these studies, there are different ways of defining risk intervals, i.e. the time frame over which an event is at risk (or likely to occur) for an entity. Research on registered unemployment in Poland shows a high percentage of people returning to the labour office and registering again. The aim of the article is assessment of the risk of subsequent registrations in the labour office depending on selected characteristics of the unemployed: gender, age, education, and seniority. In the study, methods of survival analysis were used. The results obtained for four models being an extension of the Cox proportional hazard model were compared. The Anderson‑Gil model does not distinguish between first and next events. The number of events that occurred is important. Two Prentince‑Williams‑Peterson conditional models and the Wei, Lin and Weissfeld models are based on the Cox stratified model. The strata are consecutive events. They differ in the way risk intervals are determined. In the analysed period, only age and education influenced the risk of multiple registrations at the Poviat Labour Office in Szczecin. Gender and seniority did not have a significant impact on this risk. The analysis performed for subsequent registrations confirmed the impact of the same features on the first subsequent registration. In general, it can be stated that the analysed characteristics of the unemployed did not have a significant impact on the second and subsequent returns to the labour office.

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Scattering of an eddy advected by a current towards a topographic obstacle

Journal of Fluid Mechanics ◽

10.1017/s0022112099006795 ◽

2000 ◽

Vol 402 ◽

pp. 211-223 ◽

Cited By ~ 13

Author(s):

MELVIN E. STERN

Keyword(s):

Dipole Moment ◽

Constant Velocity ◽

Grazing Incidence ◽

Plane Motion ◽

Basic Flow ◽

Homogeneous Fluid ◽

Azimuthal Mode ◽

Main Effect ◽

A Current ◽

Stratified Model

Contour dynamics is used to compute the two-dimensional (f-plane) motion of an initially circularly symmetric barotropic eddy with piecewise-uniform vorticity as it is advected around a circular obstacle by a uniform upstream current. For grazing incidence of this ‘shielded’ eddy (compensating positive and negative vorticity) the main effect of the vortex images (inside the obstacle) is to change the speed of those particles in the outer portion of the eddy that are closest to the obstacle; a lesser velocity is induced on the oppositely signed vortices near the eddy centre. The result is a systematic separation of the centroids of the ± vortices in the eddy, and the eddy emerges far downstream with an invariant dipole moment (m = 1 azimuthal mode). This causes the eddy to move with a constant velocity V normal to the uniform basic flow. The ratio of the numerically computed V to the accompanying far-field dipole moment agrees with a previous analytical theory for a completely isolated eddy subjected to a small-amplitude m = 1 initial disturbance. The scattering effect might be realizable in a rotating homogeneous fluid by translating a cylinder relative to an otherwise stationary eddy. Application to a density-stratified model is suggested.

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