Results 21 to 30 of about 5,051 (115)

Halin's Grid Theorem for Digraphs

Journal of Graph Theory, EarlyView.
ABSTRACT Halin showed that every thick end of every graph contains an infinite grid. We extend Halin's theorem to digraphs. More precisely, we show that for every infinite family ℛ ${\rm{ {\mathcal R} }}$ of disjoint equivalent out‐rays there is a grid whose vertical rays are contained in ℛ ${\rm{ {\mathcal R} }}$.
Florian Reich
wiley   +1 more source

Computing Bonds Between Formal Contexts

Mathematical Methods in the Applied Sciences, EarlyView.
ABSTRACT The notion of bond was introduced as a technique to aggregate information from multiple datasets without modifying the information already present in each of the datasets. This notion has been extended to several fuzzy frameworks, including the residuated lattice setting, which we also consider in this paper.
Roberto G. Aragón, Jesús Medina, Samuel Molina‐Ruiz   +2 more
wiley   +1 more source

Exact Solutions for the Moving Firefighter Problem on Trees

Networks, EarlyView.
ABSTRACT The moving firefighter problem (MFP) is a more realistic variant of the classic firefighter problem (FP), where firefighters require time for both travel and defense. Unfortunately, the only known exact solution for the MFP does not scale. In this paper, we establish that the MFP is NP‐complete on trees of maximum degree three and present four
Mauro A. Montenegro‐Meza, Uriel Corona‐Bermúdez, Rolando Menchaca‐Méndez, Ricardo Menchaca‐Méndez, José Alejandro Cornejo‐Acosta   +4 more
wiley   +1 more source

A structurally localized ensemble Kalman filtering approach

Quarterly Journal of the Royal Meteorological Society, EarlyView.
We derive an inherently localized ensemble Kalman filtering (EnKF) approach, avoiding the need for any auxiliary localization technique. The idea is to first use the variational Bayesian optimization to approximate the (continuous) state analysis probability density function (pdf) by a product of independent marginal pdfs corresponding to small ...
Boujemaa Ait‐El‐Fquih, Ibrahim Hoteit   +1 more
wiley   +1 more source

Modelling Suicide‐Related Communication Dynamics: A Socio‐Cybernetic Framework for Governance

Systems Research and Behavioral Science, EarlyView.
ABSTRACT Suicide‐related phenomena (SPS) are often approached through individual‐level risk factors or moral framings, yet their population‐level dynamics depend critically on how ‘suicide’ becomes observable, circulates and is governed across functionally differentiated systems.
Enrique Fernández Vilas, Juan R. Coca
wiley   +1 more source

Monetary Policy, Investor Sentiment and Stock Price Bubble: Evidence From China

Accounting &Finance, EarlyView.
ABSTRACT The empirical results indicate that an increase in interest rates may stimulate a significant and persistent stock price bubble, which is consistent with rational asset price bubble theory. This finding suggests that central banks should implement anti‐turbulent monetary policy with caution, since inappropriate tightening may unintentionally ...
Jiahao Gong, Haofan Qiang, Xiaojian Niu, Chante Jian Ding   +3 more
wiley   +1 more source

ReMoDe – Recursive modality detection in distributions of ordinal data

British Journal of Mathematical and Statistical Psychology, EarlyView.
Abstract The detection of the number of modes in distributions of ordinal data is relevant for applied researchers across disciplines, from uncovering polarization to detecting incidence groups in clinical symptom scales. Yet, established modality detection methods are either purely descriptive or not developed for ordinal data.
Madlen Hoffstadt, Lourens Waldorp, Javier Garcia‐Bernardo, Han van der Maas   +3 more
wiley   +1 more source

Financial Statement Information and Equity Value: The Role of Real Options Characteristics

Financial Management, EarlyView.
ABSTRACT This paper examines whether firm‐specific real options characteristics are equity value‐relevant beyond valuation estimates anchored in financial statements. Using extensive historical data for the United Kingdom, we assess and compare the forecast accuracy and explanatory power for stock prices of equity valuation models based on residual ...
Mingyu (Chandler) Chen, Colin Clubb, Tarik Driouchi   +2 more
wiley   +1 more source

On Exponential‐Family INGARCH Models

Journal of Time Series Analysis, EarlyView.
ABSTRACT A range of integer‐valued generalised autoregressive conditional heteroscedastic (INGARCH) models have been proposed in the literature, including those based on conditional Poisson, negative binomial and Conway‐Maxwell‐Poisson distributions. This note considers a larger class of exponential‐family INGARCH models, showing that maximum empirical
Alan Huang, Thomas Fung, Kyle Macaskill, Rowan Aukes   +3 more
wiley   +1 more source

Robust CDF‐Filtering of a Location Parameter

Journal of Time Series Analysis, EarlyView.
ABSTRACT This paper introduces a novel framework for designing robust filters associated with signal plus noise models having symmetric observation density. The filters are obtained by a recursion where the innovation term is a transform of the cumulative distribution function of the residuals.
Leopoldo Catania, Andrew C. Harvey, Alessandra Luati   +2 more
wiley   +1 more source