Search results for "Nonparametric"
showing 10 items of 427 documents
Efficiency in the eurobond market: application of nonparametric techniques
2007
The aim of this article is to analyse the efficiency of eurobond issuers within the primary market, from 1995 to 2000. The study includes a reference to theoretical discussion and to the methodology used; detailed explanation of the variables considered which, in order to supplement those strictly financial, include others such as spread from Interest Rate Risk (IRR) and respective swap; rating, duration and size; and macroeconomic fundamentals of the issuer country. Results and conclusions obtained from the static and dynamic efficiency analyses are then illustrated and discussed.
Regulation of ghrelin receptor by microbial and inflammatory signals in human osteoblasts
2019
Made available in DSpace on 2019-10-06T16:29:44Z (GMT). No. of bitstreams: 0 Previous issue date: 2019-04-25. Added 1 bitstream(s) on 2019-10-09T18:35:25Z : No. of bitstreams: 1 S1806-83242019000100221.pdf: 2536737 bytes, checksum: 9a25b4f5849a4b7f35298e8e3e000889 (MD5) Recently, it has been suggested that the anti-inflammatory hormone ghrelin (GHRL) and its receptor GHS-R may play a pivotal role in periodontal health and diseases. However, their exact regulation and effects in periodontitis are not known. The aim of this in-vitro study was to investigate the effect of microbial and inflammatory insults on the GHS-R1a expression in human osteoblast-like cells. MG-63 cells were exposed to in…
Interactions of pharmaceutical companies with world countries, cancers and rare diseases from Wikipedia network analysis
2019
AbstractUsing the English Wikipedia network of more than 5 million articles we analyze interactions and interlinks between the 34 largest pharmaceutical companies, 195 world countries, 47 rare renal diseases and 37 types of cancer. The recently developed algorithm using a reduced Google matrix (REGOMAX) allows us to take account both of direct Markov transitions between these articles and also of indirect transitions generated by the pathways between them via the global Wikipedia network. This approach therefore provides a compact description of interactions between these articles that allows us to determine the friendship networks between them, as well as the PageRank sensitivity of countr…
A non-parametric segmentation methodology for oral videocapillaroscopic images
2014
We aim to describe a new non-parametric methodology to support the clinician during the diagnostic process of oral videocapillaroscopy to evaluate peripheral microcirculation. Our methodology, mainly based on wavelet analysis and mathematical morphology to preprocess the images, segments them by minimizing the within-class luminosity variance of both capillaries and background. Experiments were carried out on a set of real microphotographs to validate this approach versus handmade segmentations provided by physicians. By using a leave-one-patient-out approach, we pointed out that our methodology is robust, according to precision-recall criteria (average precision and recall are equal to 0.9…
Interspecific associations among larval helminths in fish
2001
Various processes can generate associations between the larvae of different helminth species in their fish intermediate or paratenic host. We investigated the pairwise associations among larval helminth species in eight different fish populations, using two different coefficients of associations, in order to determine in what situations they are strongest. All helminth species included use the fish studied as either their second intermediate host or their paratenic host, and are acquired by the fish when it ingests an infected first intermediate host. The intensity of infection correlated positively with fish length for most helminth species. Pairs of species which both exhibited positive c…
Therapeutic management and evolution of chronic hepatitis B: does HIV still have an impact? The EPIB 2012 study
2015
EA Pôle MERS Hors CT hors EJ; International audience; Background & Aims: To compare the management of chronic hepatitis B (CHB) and its evolution over time in currently followed HIV-positive and HIV-negative patients. Methods: A total of 709 consecutive patients with past or present positive HBs antigenemia seen in October 2012 in 19 French participating centres were included. The data were retrospectively collected from the first visit onwards through standardized questionnaires. Results: Chronic hepatitis B was less often assessed in the 299 HIV-positive patients, who were older, more likely to be male, excessive alcohol drinkers and HBe antigen-, HCV- and HDV-positive. They were also fol…
Hepatocellular Carcinoma Presenting at Contrast-Enhanced Multi–Detector-Row Computed Tomography or Gadolinium-Enhanced Magnetic Resonance Imaging as …
2012
OBJECTIVE: The objective of the study was to measure growth rate and to determine the optimal interval time for imaging follow-up of hepatocellular carcinomas (HCCs) presenting at multi-detector-row computed tomography (MDCT) or magnetic resonance imaging (MRI) as small, indeterminate lesions. METHODS: We included patients with cirrhosis with HCC initially presenting as indeterminate lesion of 2 cm or less at MDCT or MRI August 2005 to August 2009 and with available imaging follow-up. Measures of tumor growth included tumor volume doubling time (TVDT), tumor percentual diameter increase, and tumor percentual volume increase. RESULTS: We examined 48 patients (mean age, 64 years) with 69 HCCs…
Prognostic indicators of successful endoscopic sclerotherapy for prevention of rebleeding from oesophageal varices in cirrhosis: a long-term cohort s…
2000
Abstract Background. Although band ligation is now recommended for prevention of rebleeding from oesophageal varices in cirrhosis, sclerotherapy is still widely used. Patients submitted to chronic sclerotherapy undergo several endoscopies and experience a large number of serious complications. However, long-term outcome is poorly defined. Aims. To assess the clinical course and prognostic indicators of patients undergoing chronic sclerotherapy for prevention of variceal rebleeding as a basis for future evaluation of long-term band ligation outcome. Methods. Prospective cohort study prognostic analysis by the Cox proportional hazards model. Results. A total of 218 consecutive cirrhotic patie…
Nonparametric estimation of quantile versions of the Lorenz curve
2018
Estimators of quantile versions of the Lorenz curve are proposed. The pointwise consistency and asymptotic normality of the estimators is proved. The efficiency of the estimators is also studied in simulations
Revisiting the quiet life hypothesis in banking using nonparametric techniques
2014
Early studies testing the quiet life hypothesis in banking found strong evidence that banks in more concentrated markets exhibit lower cost efficiency levels. More recent studies have reexamined the issue in different contexts, with mixed results. These approaches are based on stipulating a linear re- lationship between market power and efficiency in banking, which might be problematic, as suggested by the literature on efficiency analysis. We explore how bank cost efficiency measures are related to market power using flexible techniques, which are more consistent with those employed to measure efficiency in the first stage of the analysis. Our study focuses on the Spanish banking industry,…