Medición de las oportunidades de arbitraje en los mercados financieros con precios de venta menores que los de compra

En este trabajo se propone a nivel teórico un modelo con el que se pretende explicar la situación laboral de los individuos, teniendo en Cuenta que en el proceso de incorporación al ámbito laboral de cualquier persona deben distinguirse dos decisiones diferentes: su propia opción de actividad o inactividad laboral y las decisiones de contratación de los empresarios. Es decir, en el modelo propuesto se supone que los consumidores tratan de maximizar su utilidad, sujetos a sus restricciones temporal y de gasto, pero son los empresarios los que determinan en última instancia si van a estar ocupados O desempleado

Projective system approach to the martingale characterization of the absence of arbitrage

The equivalence between the absence of arbitrage and the existence of an equivalent martingale measure fails when an infinite number of trading dates is considered. By enlarging the set of states of nature and the probability measure through a projective system of topological spaces and Radon measures, we characterize the absence of arbitrage when the time set is countable

Medición de las oportunidades de arbitraje en los mercados financieros con precios de venta menores que los de compra.

En este trabajo se propone a nivel teórico un modelo con el que se pretende explicar la situación laboral de los individuos, teniendo en Cuenta que en el proceso de incorporación al ámbito laboral de cualquier persona deben distinguirse dos decisiones diferentes: su propia opción de actividad o inactividad laboral y las decisiones de contratación de los empresarios. Es decir, en el modelo propuesto se supone que los consumidores tratan de maximizar su utilidad, sujetos a sus restricciones temporal y de gasto, pero son los empresarios los que determinan en última instancia si van a estar ocupados O desempleadosArbitraje; Mercados financieros;

PROJECTIVE SYSTEM APPROACH TO THE MARTINGALE CHARACTERIZATION OF THE ABSENCE OF ARBITRAGE

The equivalence between the absence of arbitrage and the existence of an equivalent martingale measure fails when an infinite number of trading dates is considered. By enlarging the set of states of nature and the probability measure through a projective system of topological spaces and Radon measures, we characterize the absence of arbitrage when the time set is countable.

The average-of-awards rule for claims problems

Financiado para publicación en acceso aberto: Universidade de Vigo/CISUGGiven a claims problem, the average-of-awards rule (AA) selects the expected value of the uniform distribution over the set of awards vectors. The AA rule is the center of gravity of the core of the coalitional game associated with a claims problem, so it corresponds to the core-center. We show that this rule satisfies a good number of properties so as to be included in the inventory of division rules. We also provide several representations of the AA rule and a procedure to compute it in terms of the parameters that define the problem.Agencia Estatal de Investigación | Ref. MTM2017-87197-C3-2-PAgencia Estatal de Investigación | Ref. PID2019-106281GB-I0

An algorithm to compute the average-of-awards rule for claims problems with an application to the allocation of CO2 emissions

The set of awards vectors for a claims problem coincides with the core of the associated coalitional game. We analyze the structure of this set by defining for each group of claimants a, so called, utopia game, whose core comprises the most advantageous imputations available for the group. We show that, given a claims problem, the imputation set of the associated coalitional game can be partitioned by the cores of the utopia games. A rule selects for each claims problem a unique allocation from the set of awards vectors. The average-of-awards rule associates to each claims problem the geometric center of the corresponding set of awards vectors. Based on the decomposition of the imputation set, we obtain an interpretation of the average-of-awards rule as a point of fairness between stable and utopia imputations and provide a backward recurrence algorithm to compute it. To illustrate our analysis, we present an application to the distribution of CO2 emissions.Agencia Estatal de Investigación | Ref. PID2019‐106281GB‐I00Agencia Estatal de Investigación | Ref. PID2021‐124030NB‐C33Xunta de Galicia | Ref. ED481A 2021/325Universidade de Vigo/CISU

Refining the Lorenz‐ranking of rules for claims problems on restricted domains

The comparison of the central rules for claims problems, according to the Lorenz order, has been studied not only on the entire set of problems but also on some restricted domains. We provide new characterizations of the adjusted proportional rule as being Lorenz‐maximal or Lorenz‐minimal within a class of rules on the half‐domains. Using this result, we rank the adjusted proportional, the minimal overlap, and the average‐of‐awards rules by analyzing whether or not these rules satisfy progressivity and regressivity on the half‐domains. We also find that the adjusted proportional rule violates two well‐known claim monotonicity properties.Agencia Estatal de Investigación | Ref. PID2019‐106281GB‐I00Agencia Estatal de Investigación | Ref. PID2021‐124030NB‐C33Xunta de Galicia | Ref. ED481A 2021/325Universidade de Vigo/CISU

Deviation from proportionality and Lorenz-domination for claims problems

The Lorenz order is commonly used to compare rules for claims problems. In this paper, we incorporate the average of awards rule, the mean value of the set of awards vectors for a claims problem, to the ranking of the standard rules by proving some properties that are satisfied by this rule. We define a pair of coefficients, inspired by the Gini index, aimed at measuring, for any given claims problem, the discrepancy between the awards assigned by a rule and the proportional division. We generalize the proportionality deviation indices by introducing coefficients that measure the deviation between the awards selected by any two division rules. We show how these deviation indices are related to the Lorenz order.Ministerio de Ciencia, Innovación y Universidades | Ref. MTM2017-87197-C3-2-PMinisterio de Ciencia, Innovación y Universidades | Ref. PID2019-106281GB-I00Xunta de Galicia | Ref. ED481A 2021/32

COVID-19 severity and mortality in patients with CLL: an update of the international ERIC and Campus CLL study

Patients with chronic lymphocytic leukemia (CLL) may be more susceptible to Coronavirus disease 2019 (COVID-19) due to age, disease, and treatment-related immunosuppression. We aimed to assess risk factors of outcome and elucidate the impact of CLL-directed treatments on the course of COVID-19. We conducted a retrospective, international study, collectively including 941 patients with CLL and confirmed COVID-19. Data from the beginning of the pandemic until March 16, 2021, were collected from 91 centers. The risk factors of case fatality rate (CFR), disease severity, and overall survival (OS) were investigated. OS analysis was restricted to patients with severe COVID-19 (definition: hospitalization with need of oxygen or admission into an intensive care unit). CFR in patients with severe COVID-19 was 38.4%. OS was inferior for patients in all treatment categories compared to untreated (p < 0.001). Untreated patients had a lower risk of death (HR = 0.54, 95% CI:0.41–0.72). The risk of death was higher for older patients and those suffering from cardiac failure (HR = 1.03, 95% CI:1.02–1.04; HR = 1.79, 95% CI:1.04–3.07, respectively). Age, CLL-directed treatment, and cardiac failure were significant risk factors of OS. Untreated patients had a better chance of survival than those on treatment or recently treated

The evolving landscape of COVID‐19 and post‐COVID condition in patients with chronic lymphocytic leukemia: A study by ERIC, the European research initiative on CLL

In this retrospective international multicenter study, we describe the clinical characteristics and outcomes of patients with chronic lymphocytic leukemia (CLL) and related disorders (small lymphocytic lymphoma and high-count monoclonal B lymphocytosis) infected by SARS-CoV-2, including the development of post-COVID condition. Data from 1540 patients with CLL infected by SARS-CoV-2 from January 2020 to May 2022 were included in the analysis and assigned to four phases based on cases disposition and SARS-CoV-2 variants emergence. Post-COVID condition was defined according to the WHO criteria. Patients infected during the most recent phases of the pandemic, though carrying a higher comorbidity burden, were less often hospitalized, rarely needed intensive care unit admission, or died compared to patients infected during the initial phases. The 4-month overall survival (OS) improved through the phases, from 68% to 83%, p = .0015. Age, comorbidity, CLL-directed treatment, but not vaccination status, emerged as risk factors for mortality. Among survivors, 6.65% patients had a reinfection, usually milder than the initial one, and 16.5% developed post-COVID condition. The latter was characterized by fatigue, dyspnea, lasting cough, and impaired concentration. Infection severity was the only risk factor for developing post-COVID. The median time to resolution of the post-COVID condition was 4.7 months. OS in patients with CLL improved during the different phases of the pandemic, likely due to the improvement of prophylactic and therapeutic measures against SARS-CoV-2 as well as the emergence of milder variants. However, mortality remained relevant and a significant number of patients developed post-COVID conditions, warranting further investigations