An anticipative Markov modulated market

A Markovian modulation captures the trend in the market and influences the market coefficients accordingly. The different scenarios presented by the market are modeled as the distinct states of a discrete-time Markov chain. In our paper, we assume the existence of such modulation in a market and, as a novelty, we assume that it can be anticipative with respect to the future of the Brownian motion that drives the dynamics of the risky asset. By employing these own techniques of enlargement of filtrations, we solve an optimal portfolio utility problem in both a complete and an incomplete market. Many examples of anticipative Markov chains are presented for which we compute the additional gain of the investor who has a more accurate informatio

A short note on "Anticipative Portfolio Optimization"

In 1996, Pikovsky and Karatzas did one of the earliest studies on portfolio optimization problems in presence of insider information. They were able to successfully show that the knowledge of the stock price at future time is an insider information with associated unbounded value. However, when the insider information only gives an interval containing the future value of the stock price, they couldn't prove that the value of the information is finite. They made a conjecture of this result, still open according to our knowledge, and tried to convince about its validity by showing some numerical approximations. We close this conjecture by giving a proof that indeed the insider information in this case has a finite value.The authors acknowledge financial support from the Spanish Ministry of Education and Science, research project MTM2017-85618-P and MTM2015-72907-EXP

Practical Aspects of Solving Hybrid Bayesian Networks Containing Deterministic Conditionals

This is the author's final draft. Copyright 2015 WileyIn this paper we discuss some practical issues that arise in solv- ing hybrid Bayesian networks that include deterministic conditionals for continuous variables. We show how exact inference can become intractable even for small networks, due to the di culty in handling deterministic conditionals (for continuous variables). We propose some strategies for carrying out the inference task using mixtures of polyno- mials and mixtures of truncated exponentials. Mixtures of polynomials can be de ned on hypercubes or hyper-rhombuses. We compare these two methods. A key strategy is to re-approximate large potentials with potentials consisting of fewer pieces and lower degrees/number of terms. We discuss several methods for re-approximating potentials. We illustrate our methods in a practical application consisting of solv- ing a stochastic PERT network

Calibration of a wide angle stereoscopic system

This paper was published in OPTICS LETTERS and is made available as an electronic reprint with the permission of OSA. The paper can be found at the following URL on the OSA website: http://dx.doi.org/10.1364/OL.36.003064. Systematic or multiple reproduction or distribution to multiple locations via electronic or other means is prohibited and is subject to penalties under law.Inaccuracies in the calibration of a stereoscopic system appear with errors in point correspondences between both images and inexact points localization in each image. Errors increase if the stereoscopic system is composed of wide angle lens cameras. We propose a technique where detected points in both images are corrected before estimating the fundamental matrix and the lens distortion models. Since points are corrected first, errors in point correspondences and point localization are avoided. To correct point location in both images, geometrical and epipolar constraints are imposed in a nonlinear minimization problem. Geometrical constraints define the point localization in relation to its neighbors in the same image, and eipolar constraints represent the location of one point referred to its corresponding point in the other image. © 2011 Optical Society of America.Ricolfe Viala, C.; Sánchez Salmerón, AJ.; Martínez Berti, E. (2011). Calibration of a wide angle stereoscopic system. Optics Letters. 36(16):3064-3067. doi:10.1364/OL.36.003064S306430673616Zhang, Z., Ma, H., Guo, T., Zhang, S., & Chen, J. (2011). Simple, flexible calibration of phase calculation-based three-dimensional imaging system. Optics Letters, 36(7), 1257. doi:10.1364/ol.36.001257Longuet-Higgins, H. C. (1981). A computer algorithm for reconstructing a scene from two projections. Nature, 293(5828), 133-135. doi:10.1038/293133a0Ricolfe-Viala, C., & Sanchez-Salmeron, A.-J. (2010). Lens distortion models evaluation. Applied Optics, 49(30), 5914. doi:10.1364/ao.49.005914Armangué, X., & Salvi, J. (2003). Overall view regarding fundamental matrix estimation. Image and Vision Computing, 21(2), 205-220. doi:10.1016/s0262-8856(02)00154-3Devernay, F., & Faugeras, O. (2001). Straight lines have to be straight. Machine Vision and Applications, 13(1), 14-24. doi:10.1007/pl0001326

Benchmarking federated strategies in Peer-to-Peer Federated learning for biomedical data

The increasing requirements for data protection and privacy has attracted a huge research interest on distributed artificial intelligence and specifically on federated learning, an emerging machine learning approach that allows the construction of a model between several participants who hold their own private data. In the initial proposal of federated learning the architecture was centralised and the aggregation was done with federated averaging, meaning that a central server will orchestrate the federation using the most straightforward averaging strategy. This research is focused on testing different federated strategies in a peer-to-peer environment. The authors propose various aggregation strategies for federated learning, including weighted averaging aggregation, using different factors and strategies based on participant contribution. The strategies are tested with varying data sizes to identify the most robust ones. This research tests the strategies with several biomedical datasets and the results of the experiments show that the accuracy-based weighted average outperforms the classical federated averaging method

Optimal portfolio with insider information on the stochastic interest rate

We consider the optimal portfolio problem where the interest rate is stochastic and the agent has insider information on its value at a finite terminal time. The agent's objective is to optimize the terminal value of herportfolio under a logarithmic utility function. Using techniques of initial enlargement of filtration, we identify the optimal strategy and compute the value of the information. The interest rate is first assumed to be an affine diffusion, then more explicit formulas are computed for the Vasicek interest rate model where the interest rate moves according to an Ornstein-Uhlenbeck process. We show that when the interest rate process is correlated with the price process of the risky asset, the value of the information is infinite, as is usually the case for initial-enlargement-type problems. However, since the agent does not know exactly the correlation factor, this may induce an infinite loss instead of an infinite gain. Finally weakening the information own by the agent, and assuming that she only knows a lower-bound for the terminal value of the interest rate process, we show that the value of the information is finite.The first author acknowledge financial support from the Spanish Ministry of Education and Science, research projects MTM2015– 72907–EXP and MTM2013–42104–P (via FEDER funds)

4-Dimensional deformation part model for pose estimation using Kalman filter constraints

The main goal of this article is to analyze the effect on pose estimation accuracy when using a Kalman filter added to 4-dimensional deformation part model partial solutions. The experiments run with two data sets showing that this method improves pose estimation accuracy compared with state-of-the-art methods and that a Kalman filter helps to increase this accuracy

Phenotypic and Genotypic Antimicrobial Susceptibility Testing of Chlamydia trachomatis Isolates from Patients with Persistent or Clinical Treatment Failure in Spain

Chlamydia trachomatis; Sexually transmitted infection; Treatment failureChlamydia trachomatis; Infecció de transmissió sexual; Fracàs del tractamentChlamydia trachomatis; Infección transmitida sexualmente; Fracaso del tratamientoThe aim of this multicentre project (seven hospitals across the Spanish National Health Service) was to study the phenotypic and genotypic susceptibility of C. trachomatis to the main antimicrobials used (macrolides, doxycycline, and quinolones) in isolates from patients with clinical treatment failure in whom reinfection had been ruled out. During 2018–2019, 73 clinical isolates were selected. Sixty-nine clinical specimens were inoculated onto confluent McCoy cell monolayers for phenotypic susceptibility testing. The minimum inhibitory concentration for azithromycin and doxycycline was defined as the lowest concentration associated with an at least 95% reduction in inclusion-forming units after one passage in the presence of the antibiotic compared to the initial inoculum for each strain (control). Sequencing analysis was performed for the genotypic detection of resistance to macrolides, analysing mutations in the 23S rRNA gene (at positions 2057, 2058, 2059, and 2611), and quinolones, analysing a fragment of the gyrA gene, and searching for the G248T mutation (Ser83->Ile). For tetracyclines, in-house RT-PCR was used to test for the tet(C) gene. The phenotypic susceptibility testing was successful for 10 isolates. All the isolates had minimum inhibitory concentrations for azithromycin ≤ 0.125 mg/L and for doxycycline ≤ 0.064 mg/L and were considered sensitive. Of the 73 strains studied, no mutations were found at positions T2611C or G248T of the gyrA gene. We successfully sequenced 66 isolates. No macrolide resistance-associated mutations were found at positions 2057, 2058, 2059, or T2611C. None of the isolates carried the tet(C) gene. We found no evidence for genomic resistance in this large, clinically relevant dataset.This study was funded by Instituto de Salud Carlos III (ISCIII) via the project “PI17/01886” and co-funded by the European Union

Museums as agents of community building in the city of Almeria. Analysis of the «Culture served in ceramics» experience

©2023. The authors. This document is made available under the CC-BY-NC-SA 4.0 license http://creativecommons.org/licenses/by-nc-sa/4.0/ This document is the published version of a Published Work that appeared in final form in Diferents. To access the final edited and published work see https://dx.doi.org/10.6035/diferents.7655Este artículo presenta los principales resultados de la experiencia «Cultura servida en cerámica», desarrollada en la ciudad de Almería con la implicación de diferentes colectivos vulnerables en un entorno museístico. Con este propósito se plantea el objetivo de analizar el impacto que a nivel educativo ha tenido este proyecto de intervención comunitaria entre sus participantes. La metodología empleada fue de tipo cualitativa, por medio de entrevistas y grupos de discusión. Los informantes fueron seleccionados a través de muestreo no probabilístico, y por conveniencia. Los resultados indican que las actitudes de los destinatarios del programa tuvieron una gran influencia en su contexto cultural, posibilidades artísticas, educativas, así como en la formación de nuevas redes sociales. Se puede concluir que la iniciativa desarrollada es idónea para establecer un marco de referencia que promueva una reflexión crítica y participativa en el espacio museístico de colectivos en riesgo de exclusión.This paper presents the main results of the «Culture served in ceramics» experience, developed in the city of Almería, with the involvement of different vulnerable groups in the museum environment. With this purpose, the objective is to analyze the impact that this community intervention project has had among its participants at an educational level. The methodology used was qualitative, through interviews and discussion groups. The participants were selected through non-probabilistic sampling, and for convenience. The results show that the attitudes of the beneficiaries of the program had a great impact regarding their cultural context, artistic, educational possibilities, as well as the creation of new social networks. It should be concluded that the initiative developed becomes an ideal proposal to establish a reference framework that favors a critical and participatory reflection from the museum space from groups at risk of exclusion