Mobile network sharing trends in developing and developed mobile markets (regulations and market forces): A comparison between selected Latin American markets and Sweden

The present document has the objective of analyzing the impact of several factors that are part of mobile telecom markets into the feasibility of sharing resources as a strategy for operators to deploy their networks in a cost-efficient manner and cope with the ever increasing amount of data traffic. These factors include the situation of the operators with their distribution of market shares, the nature of national regulatory authorities, and their lines of action. The study comprises the description and analysis of three markets: Ecuador, Chile, and Sweden, as they pose very different scenarios and are useful to prove the contrast present in two different regions of the world. The results of this research work show that in order to ease the adoption of network sharing in a market, a state of fair competition must be encouraged, reflected by a good distribution of market shares between operators. This is for the most part a task of the regulators, as they must make sure to award resources to operators in an equitable manner, as well as to identify the right moments to introduce new actors into the market, as it is observed in the cases of Chile and Sweden. Additionally, the regulators must have a liberal approach in their decisions, by permitting both active and passive network sharing, as this study shows that this is not the case in Chile and Ecuador so far

Pelvic inflammatory disease: clinical feature, risk factors, treatment, and prevention

Pelvic Inflammatory Disease (PID) is a significant public health concern with severe repercussions for reproductive health, including ectopic pregnancies, chronic pelvic pain, and tubal infertility. This study provides a comprehensive examination of PID, covering its clinical characteristics, risk factors, etiological agents, diagnostic methods, treatment options, and preventive strategies. PID encompasses a variety of inflammatory disorders of the upper female genital tract caused by pathogens such as Neisseria gonorrhoeae, Chlamydia trachomatis, vaginal flora, and other bacteria. Despite a decline in PID cases associated with N. gonorrhoeae and C. trachomatis, these pathogens remain substantial contributors. Key risk factors include age under 25, multiple sexual partners, unprotected sex, early sexual debut and a history of sexually transmitted diseases (STDs) or previous PID. Diagnosis relies primarily on clinical evaluation, with symptoms ranging from mild pelvic discomfort to severe abdominal pain, complicating timely diagnosis. Effective treatment involves the use of empirical broad-spectrum antibiotics. Preventive strategies emphasize early detection and treatment of STIs, adherence to screening guidelines, and measures to prevent recurrent PID episodes. Effective management of PID requires early detection, prompt intervention, and comprehensive preventive measures targeting both initial and recurrent cases. Adherence to STI screening and treatment protocols is crucial in reducing PID incidence and associated complications. Continued research is vital to enhance the understanding of pathogenic mechanisms and optimize treatment protocols, thereby improving the quality of life for women affected by PID

Statistical Models of Top-kk Partial Orders

In many contexts involving ranked preferences, agents submit partial orders over available alternatives. Statistical models often treat these as marginal in the space of total orders, but this approach overlooks information contained in the list length itself. In this work, we introduce and taxonomize approaches for jointly modeling distributions over top-$k$ partial orders and list lengths $k$, considering two classes of approaches: composite models that view a partial order as a truncation of a total order, and augmented ranking models that model the construction of the list as a sequence of choice decisions, including the decision to stop. For composite models, we consider three dependency structures for joint modeling of order and truncation length. For augmented ranking models, we consider different assumptions on how the stop-token choice is modeled. Using data consisting of partial rankings from San Francisco school choice and San Francisco ranked choice elections, we evaluate how well the models predict observed data and generate realistic synthetic datasets. We find that composite models, explicitly modeling length as a categorical variable, produce synthetic datasets with accurate length distributions, and an augmented model with position-dependent item utilities jointly models length and preferences in the training data best, as measured by negative log loss. Methods from this work have significant implications on the simulation and evaluation of real-world social systems that solicit ranked preferences.Comment: 9 pages, 5 figure

Multilevel Particle Filters for Partially Observed McKean-Vlasov Stochastic Differential Equations

In this paper we consider the filtering problem associated to partially observed McKean-Vlasov stochastic differential equations (SDEs). The model consists of data that are observed at regular and discrete times and the objective is to compute the conditional expectation of (functionals) of the solutions of the SDE at the current time. This problem, even the ordinary SDE case is challenging and requires numerical approximations. Based upon the ideas in [3, 12] we develop a new particle filter (PF) and multilevel particle filter (MLPF) to approximate the afore-mentioned expectations. We prove under assumptions that, for $\epsilon>0$, to obtain a mean square error of $\mathcal{O}(\epsilon^2)$ the PF has a cost per-observation time of $\mathcal{O}(\epsilon^{-5})$ and the MLPF costs $\mathcal{O}(\epsilon^{-4})$ (best case) or $\mathcal{O}(\epsilon^{-4}\log(\epsilon)^2)$ (worst case). Our theoretical results are supported by numerical experiments.Comment: 21 pages, 2 figure

Unbiased Parameter Estimation for Partially Observed Diffusions

In this article we consider the estimation of static parameters for partially observed diffusion process with discrete-time observations over a fixed time interval. In particular, we assume that one must time-discretize the partially observed diffusion process and work with the model with bias and consider maximizing the resulting log-likelihood. Using a novel double randomization scheme, based upon Markovian stochastic approximation we develop a new method to unbiasedly estimate the static parameters, that is, to obtain the maximum likelihood estimator with no time discretization bias. Under assumptions we prove that our estimator is unbiased and investigate the method in several numerical examples, showing that it can empirically out-perform existing unbiased methodology.Comment: 27 pages, 8 figure

Radiation Induced Point and Cluster-Related Defects with Strong Impact to Damage Properties of Silicon Detectors

This work focuses on the investigation of radiation induced defects responsible for the degradation of silicon detectors. Comparative studies of the defects induced by irradiation with 60Co- rays, 6 and 15 MeV electrons, 23 GeV protons and 1 MeV equivalent reactor neutrons revealed the existence of point defects and cluster related centers having a strong impact on damage properties of Si diodes. The detailed relation between the microscopic reasons as based on defect analysis and their macroscopic consequences for detector performance are presented. In particular, it is shown that the changes in the Si device properties after exposure to high levels of 60Co- doses can be completely understood by the formation of two point defects, both depending strongly on the Oxygen concentration in the silicon bulk. Specific for hadron irradiation are the annealing effects which decrease resp. increase the originally observed damage effects as seen by the changes of the depletion voltage. A group of three cluster related defects, revealed as deep hole traps, proved to be responsible specifically for the reverse annealing. Their formation is not affected by the Oxygen content or Si growth procedure suggesting that they are complexes of multi-vacancies located inside extended disordered regions.Comment: 14 pages, 15 figure