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Several Versions (several + version)

Distribution by Scientific Domains
Business, Economics, Finance and Accounting37%

Selected Abstracts

Real-time signal processing by adaptive repeated median filters

INTERNATIONAL JOURNAL OF ADAPTIVE CONTROL AND SIGNAL PROCESSING, Issue 5 2010
K. Schettlinger
Abstract In intensive care, a basic goal is to extract the signals from very noisy time series in real time. We propose a robust online filter with an adaptive window width, which yields a smooth representation of the denoised data in stable periods and which is also able to trace typical patterns such as level shifts or trend changes with small time delay. Several versions of this method are evaluated and compared with a simulation study and on real data. Copyright © 2009 John Wiley & Sons, Ltd. [source]

Short-term forecasting of GDP using large datasets: a pseudo real-time forecast evaluation exercise,

JOURNAL OF FORECASTING, Issue 7 2009
G. Rünstler
Abstract This paper performs a large-scale forecast evaluation exercise to assess the performance of different models for the short-term forecasting of GDP, resorting to large datasets from ten European countries. Several versions of factor models are considered and cross-country evidence is provided. The forecasting exercise is performed in a simulated real-time context, which takes account of publication lags in the individual series. In general, we find that factor models perform best and models that exploit monthly information outperform models that use purely quarterly data. However, the improvement over the simpler, quarterly models remains contained. Copyright © 2009 John Wiley & Sons, Ltd. [source]

ESTIMATED DYNAMIC STOCHASTIC GENERAL EQUILIBRIUM MODEL OF THE TAIWANESE ECONOMY

PACIFIC ECONOMIC REVIEW, Issue 2 2009
Wing Leong Teo
Several versions of the model with different representations of Taiwanese monetary policy are estimated using Bayesian techniques. The major findings are that: (i) monetary policy in Taiwan is best described by a money supply growth rate rule; (ii) the Taiwanese economy is more flexible than the Euro area economy; and (iii) export price mark-up and investment-specific technology shocks are the main driving forces of output growth fluctuations in Taiwan. [source]

Hedging Affecting Firm Value via Financing and Investment: Evidence from Property Insurance Use

FINANCIAL MANAGEMENT, Issue 3 2010
Hong Zou
I provide evidence about the value effects of alternative risk management by examining corporate purchase of property insurance, a commonly used pure hedge of asset-loss risks. Using an insurance data set from China, I find that there is an inverted U-shape effect of the extent of property insurance use on firm value measured by several versions of Tobin's Q. Therefore, the use of property insurance, to a certain degree, has a positive effect on firm value; however, over insurance appears detrimental to firm value. Given that the inflection points occur at relatively high levels of the observed insurance spending, insurance use appears beneficial to the majority of my sample firms. The estimated average hedging premium is about 1.5%. I demonstrate that an avenue for insurance to create value in China is that it helps firms secure valuable new debt financing and enhance investment. [source]

Shifted factor analysis,Part II: Algorithms

JOURNAL OF CHEMOMETRICS, Issue 7 2003
Sungjin Hong
Abstract We previously proposed a family of models that deal with the problem of factor position shift in sequential data. We conjectured that the added information provided by fitting the shifts would make the model parameters identifiable, even for two-way data. We now derive methods of parameter estimation and give the results of experiments with synthetic data. The alternating least squares (ALS) approach is not fully suitable for estimation, because factor position shifts destroy the multilinearity of the latent structure. Therefore an alternative ,quasi-ALS' approach is developed, some of its practical and theoretical properties are dealt with and several versions of the quasi-ALS algorithm are described in detail. These procedures are quite computation-intensive, but analysis of synthetic data demonstrates that the algorithms can recover shifting latent factor structure and, in the situations tested, are robust against high error levels. The results of these experiments also provide strong empirical support for our conjecture that the two-way shifted factor model has unique solutions in at least some circumstances. Copyright © 2003 John Wiley & Sons, Ltd. [source]

Analyzing software evolution through feature views

JOURNAL OF SOFTWARE MAINTENANCE AND EVOLUTION: RESEARCH AND PRACTICE, Issue 6 2006
Orla Greevy
Abstract Features encapsulate the domain knowledge of a software system and thus are valuable sources of information for a reverse engineer. When analyzing the evolution of a system, we need to know how and which features were modified to recover both the change intention and extent, namely which source artifacts are affected. Typically, the implementation of a feature crosscuts a number of source artifacts. To obtain a mapping between features and the source artifacts, we exercise the features and capture their execution traces. However, this results in large traces that are difficult to interpret. To tackle this issue we compact the traces into simple sets of source artifacts that participate in a feature's runtime behavior. We refer to these compacted traces as feature views. Within a feature view, we partition the source artifacts into disjoint sets of characterized software entities. The characterization defines the level of participation of a source entity in the features. We then analyze the features over several versions of a system and we plot their evolution to reveal how and which features were affected by code changes. We show the usefulness of our approach by applying it to a case study where we address the problem of merging parallel development tracks of the same system. Copyright © 2006 John Wiley & Sons, Ltd. [source]

REVISITING CHILD-BASED OBJECTIONS TO COMMERCIAL SURROGACY

BIOETHICS, Issue 7 2010
JASON K.M. HANNA
ABSTRACT Many critics of commercial surrogate motherhood argue that it violates the rights of children. In this paper, I respond to several versions of this objection. The most common version claims that surrogacy involves child-selling. I argue that while proponents of surrogacy have generally failed to provide an adequate response to this objection, it can be overcome. After showing that the two most prominent arguments for the child-selling objection fail, I explain how the commissioning couple can acquire parental rights by paying the surrogate only for her reproductive labor. My explanation appeals to the idea that parental rights are acquired by those who have claims over the reproductive labor that produces the child, not necessarily by those who actually perform the labor. This account clarifies how commercial surrogacy differs from commercial adoption. In the final section of the paper, I consider and reject three further child-based objections to commercial surrogacy: that it establishes a market in children's attributes, that it requires courts to stray from the best interests standard in determining custodial rights, and that it requires the surrogate to neglect her parental responsibilities. Since each of these objections fails, children's rights probably do not pose an obstacle to the acceptability of commercial surrogacy arrangements. [source]

Rationally engineered biotransformation of p -nitrophenol

BIOTECHNOLOGY PROGRESS, Issue 3 2010
Matthew de la Peńa Mattozzi
Abstract An operon encoding enzymes responsible for degradation of the EPA priority contaminant para -nitrophenol (PNP) from Pseudomonas sp. ENV2030 contains more genes than would appear to be necessary to mineralize PNP. To determine some necessary genes for PNP degradation, the genes encoding the proposed enzymes in the degradation pathway (pnpADEC) were assembled into a broad-host-range, BioBricks-compatible vector under the control of a constitutive promoter. These were introduced into Escherichia coli DH10b and two Pseudomonas putida strains, one with a knockout of the aromatic transport TtgB and the parent with the native transporter. The engineered strains were assayed for PNP removal. E. coli DH10b harboring several versions of the refactored pathway was able to remove PNP from the medium up to a concentration of 0.2 mM; above which PNP was toxic to E. coli. A strain of P. putida harboring the PNP pathway genes was capable of removing PNP from the medium up to 0.5 mM. When P. putida harboring the native PNP degradation cluster was exposed to PNP, pnpADEC were induced, and the resulting production of ,-ketoadipate from PNP induced expression of its chromosomal degradation pathway (pcaIJF). In contrast, pnpADEC were expressed constitutively from the refactored constructs because none of the regulatory genes found in the native PNP degradation cluster were included. Although P. putida harboring the refactored construct was incapable of growing exclusively on PNP as a carbon source, evidence that the engineered pathway was functional was demonstrated by the induced expression of chromosomal pcaIJF. © 2010 American Institute of Chemical Engineers Biotechnol. Prog., 2010 [source]