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Favorable Performance (favorable + performance)

Distribution by Scientific Domains

Business, Economics, Finance and Accounting	50%

Selected Abstracts

A New Type of Bismuth Electrode for Electrochemical Stripping Analysis Based on the Ammonium Tetrafluorobismuthate Bulk-Modified Carbon Paste

ELECTROANALYSIS, Issue 13 2010
Hanna Sopha
Abstract A carbon paste electrode bulk-modified with ammonium tetrafluorobismuthate (BiF4 -CPE) was developed and examined in the anodic stripping voltammetric mode for measurement of selected trace heavy metals. The BiF4 -CPE has revealed a favorable performance in more acidic solutions (pH,0.5,2.5) in the presence of dissolved oxygen for Cd(II) and Pb(II) as model metal ions at the low ,g L,1 concentration level. In comparison with the bismuth-oxide bulk-modified carbon paste electrode and the other two bismuth film-plated carbonaceous substrate electrodes examined, the BiF4 -CPE proved to be another attractive variant of the environmentally friendly bismuth-based electrodes, particularly convenient for analysis of acidified water samples. [source]

A semiparametric model for binary response and continuous outcomes under index heteroscedasticity

JOURNAL OF APPLIED ECONOMETRICS, Issue 5 2009
Roger Klein
This paper formulates a likelihood-based estimator for a double-index, semiparametric binary response equation. A novel feature of this estimator is that it is based on density estimation under local smoothing. While the proofs differ from those based on alternative density estimators, the finite sample performance of the estimator is significantly improved. As binary responses often appear as endogenous regressors in continuous outcome equations, we also develop an optimal instrumental variables estimator in this context. For this purpose, we specialize the double-index model for binary response to one with heteroscedasticity that depends on an index different from that underlying the ,mean response'. We show that such (multiplicative) heteroscedasticity, whose form is not parametrically specified, effectively induces exclusion restrictions on the outcomes equation. The estimator developed exploits such identifying information. We provide simulation evidence on the favorable performance of the estimators and illustrate their use through an empirical application on the determinants, and affect, of attendance at a government-financed school. Copyright © 2009 John Wiley & Sons, Ltd. [source]

Thyroid tumor marker genomics and proteomics: Diagnostic and clinical implications

JOURNAL OF CELLULAR PHYSIOLOGY, Issue 3 2010
Angelo Carpi
Two systems biology concepts, genomics and proteomics, are highlighted in this review. These techniques are implemented to optimize the use of thyroid tumor markers (TTM). Tissue microarray studies can produce genetic maps and proteomics, patterns of protein expression of TTM derived from preoperative biopsies and specimens. For instance, papillary and medullary thyroid cancers harbor RAS, RET, and BRAF genetic mutations. Follicular thyroid cancers harbor translocations and fusions of certain genes (PAX 8 and PPAR-gamma). Proteomic analysis from various tissue sources can provide useful information regarding the overall state of a thyroid cancer cell. Understanding the molecular events related to these genetic and protein alterations can potentially clarify thyroid cancer pathogenesis and guide appropriate molecular targeted therapies. However, despite the realization that these emerging technologies hold great promise, there are still significant obstacles to the routine use of TTM. These include equivocal thyroid nodule tissue morphologic interpretations, inadequate standardization of methods, and monetary costs. Interpretative shortcomings are frequently due to the relative scarcity of cellular material from fine-needle aspiration biopsy (FNAB) specimens. This can be rectified with large needle aspiration biopsy (LNAB) techniques and is exemplified by the favorable performance of galectin-3 determinations on LNAB specimens. J. Cell. Physiol. 224: 612,619, 2010. © 2010 Wiley-Liss, Inc. [source]

A new Bayesian formulation for Holt's exponential smoothing

JOURNAL OF FORECASTING, Issue 3 2009
Robert R. Andrawis
Abstract In this paper we propose a Bayesian forecasting approach for Holt's additive exponential smoothing method. Starting from the state space formulation, a formula for the forecast is derived and reduced to a two-dimensional integration that can be computed numerically in a straightforward way. In contrast to much of the work for exponential smoothing, this method produces the forecast density and, in addition, it considers the initial level and initial trend as part of the parameters to be evaluated. Another contribution of this paper is that we have derived a way to reduce the computation of the maximum likelihood parameter estimation procedure to that of evaluating a two-dimensional grid, rather than applying a five-variable optimization procedure. Simulation experiments confirm that both proposed methods give favorable performance compared to other approaches. Copyright © 2008 John Wiley & Sons, Ltd. [source]