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New Data Set (new + data_set)
Selected AbstractsA simulation tool for designing nutrient monitoring programmes for eutrophication assessments,ENVIRONMETRICS, Issue 1 2010Janet Heffernan Abstract This paper describes a simulation tool to aid the design of nutrient monitoring programmes in coastal waters. The tool is developed by using time series of water quality data from a Smart Buoy, an in situ monitoring device. The tool models the seasonality and temporal dependence in the data and then filters out these features to leave a white noise series. New data sets are then simulated by sampling from the white noise series and re-introducing the modelled seasonality and temporal dependence. Simulating many independent realisations allows us to study the performance of different monitoring designs and assessment methods. We illustrate the approach using total oxidised nitrogen (TOxN) and chlorophyll data from Liverpool Bay, U.K. We consider assessments of whether the underlying mean concentrations of these water quality variables are sufficiently low; i.e. below specified assessment concentrations. We show that for TOxN, even when mean concentrations are at background, daily data from a Smart Buoy or multi-annual sampling from a research vessel would be needed to obtain adequate power. Copyright © 2009 Crown Copyright [source] English and Scottish overseas trade, 1300,16001ECONOMIC HISTORY REVIEW, Issue 2 2006MARTIN RORKE This article compares English and Scottish exports, from 1300,1600, using existing statistical data from England and a new data set of Scottish exports. It shows that the significant English and Scottish wool trades collapsed at almost identical rates. However, while England shifted towards exporting woollen cloth, a similar move in Scotland was weak,because of the poor quality of cloth and the urban form of the industry. In the second half of the sixteenth century, as English exports stagnated, Scottish trade began to grow, especially new and less-established commodities. This ,recovery' was based on the heavy depreciation of the Scottish currency. [source] Reconstruction of the Water Table from Self-Potential Data: A Bayesian ApproachGROUND WATER, Issue 2 2009A. Jardani Ground water flow associated with pumping and injection tests generates self-potential signals that can be measured at the ground surface and used to estimate the pattern of ground water flow at depth. We propose an inversion of the self-potential signals that accounts for the heterogeneous nature of the aquifer and a relationship between the electrical resistivity and the streaming current coupling coefficient. We recast the inversion of the self-potential data into a Bayesian framework. Synthetic tests are performed showing the advantage in using self-potential signals in addition to in situ measurements of the potentiometric levels to reconstruct the shape of the water table. This methodology is applied to a new data set from a series of coordinated hydraulic tomography, self-potential, and electrical resistivity tomography experiments performed at the Boise Hydrogeophysical Research Site, Idaho. In particular, we examine one of the dipole hydraulic tests and its reciprocal to show the sensitivity of the self-potential signals to variations of the potentiometric levels under steady-state conditions. However, because of the high pumping rate, the response was also influenced by the Reynolds number, especially near the pumping well for a given test. Ground water flow in the inertial laminar flow regime is responsible for nonlinearity that is not yet accounted for in self-potential tomography. Numerical modeling addresses the sensitivity of the self-potential response to this problem. [source] Assessing the long-run economic impact of labour law systems: a theoretical reappraisal and analysis of new time series dataINDUSTRIAL RELATIONS JOURNAL, Issue 6 2008Simon Deakin ABSTRACT Standard economic theory sees labour law as an exogenous interference with market relations and predicts mostly negative impacts on employment and productivity. We argue for a more nuanced theoretical position: labour law is, at least in part, endogenous, with both the production and the application of labour law norms influenced by national and sectoral contexts, and by complementarities between the institutions of the labour market and those of corporate governance and financial markets. Legal origin may also operate as a force shaping the content of the law and its economic impact. Time-series analysis using a new data set on legal change from the 1970s to the mid-2000s shows evidence of positive correlations between regulation and growth in employment and productivity, at least for France and Germany. No relationship, either positive or negative, is found for the UK and, although the United States shows a weak negative relationship between regulation and employment growth, this is offset by productivity gains. [source] National Estimates of Medication Use in Nursing Homes: Findings from the 1997 Medicare Current Beneficiary Survey and the 1996 Medical Expenditure SurveyJOURNAL OF AMERICAN GERIATRICS SOCIETY, Issue 3 2005Jalpa A. Doshi PhD Objectives: To provide the first nationwide estimates of medication use in nursing homes (NHs) and to introduce a new data set for examining drug use in long-term care facilities. Design: Cross-sectional comparison. Setting: NH medication files from two nationally representative data sets, the 1997 Medicare Current Beneficiary Survey (MCBS) and the 1996 Medical Expenditure Panel Survey,Nursing Home Component (MEPS-NHC). Participants: NH residents in the MCBS (n=929, weighted n=2.0 million) and MEPS-NHC (n=5,899, weighted n=3.1 million). Measurements: Estimates include characteristics of facilities and residents, average number of drugs used per person per month, and the prevalence and duration of use by select therapeutic drug classes. Results: NH residents received, on average, seven to eight medications each month (7.6 MCBS, 7.2 MEPS-NHC). About one-third of residents had monthly drug regimens of nine or more medications (31.8% MCBS, 32.4% MEPS-NHC). The most commonly used medications in NHs, in descending order, were analgesics and antipyretics, gastrointestinal agents, electrolytic and caloric preparations, central nervous system agents, anti-infective agents, and cardiovascular agents. Conclusion: These estimates serve as examples of the first national benchmarks of prescribing patterns in NHs. This study highlights the usefulness of the MCBS as an important new resource for examining medication use in NHs. [source] Border Effects in Passenger Air TrafficKYKLOS INTERNATIONAL REVIEW OF SOCIAL SCIENCES, Issue 4 2004Henning Klodt SUMMARY The empirical literature on border effects suggests that national borders substantially reduce the level of economic transactions. This paper adds another piece of evidence to the significance of border effects by applying a new data set which is completely independent of the data sets of previous studies. Our data refer to domestic and international passenger departures from German airports. The econometric results indicate that the German border reduces passenger air traffic by a factor of four to five. This magnitude is in line with the results of previous studies for trade and investment flows. ZUSAMMENFASSUNG Die empirische Literatur zum Einfluss von Grenzen hat gezeigt, dass nationale Grenzen den Umfang von ökonomischen Transaktionen beträchtlich reduzieren. Dieser Beitrag präsentiert einen weiteren Beleg für die Relevanz von Grenzen, indem ein neuer Datensatz ausgewertet wird, der vollständig unabhängig von den in früheren Studien verwendeten Datensätzen ist. Unsere Daten beziehen sich auf die Passagierzahlen bei nationalen und internationalen Abflügen von deutschen Flughäfen. Den Schätzergebnissen zufolge reduziert die deutsche Grenze das Passagieraufkommen im Flugverkehr um den Faktor vier bis fünf. Diese Größenordnung steht in Einklang mit den Grenzeffekten, wie sie in anderen Studien für Handels- und Investitionsströme gemessen worden sind. RÉSUMÉ La littérature empirique sur les effets des frontières suggère que le niveau des transactions économiques est fortement réduit par les frontières nationales. Cet article propose de contribuer à ce débat en utilisant une nouvelle base de données qui se différencie substantiellement de celles utilisées jusqu'à présent. Nous utilisons des données sur le nombre de passagers au départ d'aéroports allemands vers des destinations nationales et internationales. Les résultats économétriques démontrent que l'existence des frontières allemandes réduit le trafic de passagers aériens par un facteur de quatre à cinq. Cet ordre de grandeur est comparable aux études antérieures concernant le commerce et les flux d'investissement. [source] Model Development in Thermal Styrene PolymerizationMACROMOLECULAR SYMPOSIA, Issue 1 2007Bryan Matthews Abstract Summary: The thermal polymerization of styrene is usually modeled by relying on a reaction scheme and a set of equations that were developed more than three decades ago by Hui and Hamielec. Many detailed models of styrene polymerization are available in the open literature and they are mostly based on the work of Hui and Hamielec, which nearly makes this the standard to follow in explaining the behavior of polystyrene reactors. The model of Hui and Hamielec does a very nice job of describing monomer conversion data but discrepancies are seen between observed and predicted values of number and weight average molecular weights, Mn and Mw. Discrepancies in number average molecular weight seem to be the result of random noise. Discrepancies in weight average molecular weight grow as the polymerization temperature decreases and some of the trends observed in the residuals over the entire temperature range cannot be attributed to random noise. Hui and Hamielec attributed the observed deficiencies to a standard deviation of ±10% in their GPC measurements. A new data set with an experimental error of 2% for average molecular weights is presented. The set contains measured values of Mn, Mw and Mz, so the polymerization scheme has been extended to include third order moments. The data set also includes the effect of ethylbenzene as a chain transfer agent. We present the results of comparing model predictions to our measurements and the adjustments made in the original set of kinetic parameters published by Hui and Hamielec. [source] DOLLARIZATION OF DEBT CONTRACTS: EVIDENCE FROM CHILEAN FIRMSTHE DEVELOPING ECONOMIES, Issue 4 2009Miguel FUENTES F31; F49 This paper uses a new data set to estimate the causes and consequences of foreign currency debt in firms' balance sheets. The evidence from this sample of Chilean firms indicates that dollar-denominated debt increases with firms' size and degree of exposure to foreign competition. We find evidence that dollar-denominated debt combines with exchange rate movements to produce a negative balance-sheet effect that reduces firms' investment in periods of strong exchange rate depreciation. This negative balance-sheet effect is associated with long-term debt and appears to be nonlinear in the amount of real exchange rate depreciation. [source] RETURNS TO EQUITY, INVESTMENT AND Q: EVIDENCE FROM THE UKTHE MANCHESTER SCHOOL, Issue 2005SIMON PRICE Conventional wisdom has it that Tobin's Q cannot help explain aggregate investment. However, the standard linearized present-value asset price decomposition suggests that it should be able to predict other variables, such as stock returns. Using a new data set for the UK, we find that Q has strong predictive power for debt accumulation, stock returns and UK business investment. The correctly signed results on both returns and investment appear to be robust, and are supported by the commonly used and bootstrapped standard error corrections, as well as recently developed asymptotic corrections. [source] Evaluating differences in linkage disequilibrium between populationsANNALS OF HUMAN GENETICS, Issue 3 2010Birgir Hrafnkelsson Summary We propose two methods to evaluate the statistical significance of differences in linkage disequilibrium (LD) between populations, where LD is measured by the standardised parameter D,. The first method is based on bootstrapping individuals within populations in order to test LD differences for each pair of loci. Using this approach we propose a solution to the problem of testing multiple locus-pairs by means of a single test for the number of pairs that exhibit significant LD differences among populations. The second method provides the Bayesian posterior probability that one population has greater LD than the other for each locus pair. Both methods can handle genotypes with unknown phase, and are demonstrated using two data sets. For the purpose of demonstration, we apply the methods to two different sets of data from humans. First, we explore the issue of LD differences between reproductively isolated populations using a new data set of twelve Xq25 microsatellites, typed in four European populations. Second, we examine evidence for LD differences between Alzheimer cases and controls from the Icelandic population using 19 single nucleotide polymorphisms (SNPs) from a 97 kb region flanking the Apolipoprotein E (APOE) gene on chromosome 19. [source] Validation and simplification of a score predicting survival in patients irradiated for metastatic spinal cord compressionCANCER, Issue 15 2010Dirk Rades MD Abstract BACKGROUND: Based on an analysis of 1852 retrospectively evaluated patients with metastatic spinal cord compression (MSCC), a scoring system was developed to predict survival. This study was performed to validate the scoring system in a new data set. METHODS: The score included 6 prognostic factors: tumor type, interval between tumor diagnosis and MSCC, other bone or visceral metastases, ambulatory status, and duration of motor deficits. Scores ranged between 20 and 45 points, and patients were initially divided into 5 groups: those with 20 to 25 points, those with 26 to 30 points, those with 31 to 35 points, those with 36 to 40 points, and those with 41 to 45 points. To facilitate the clinical use of the score, the patients were regrouped into 3 groups: those with 20 to 30 points, those with 31 to 35 points, and those with 36 to 45 points. In this study, data of 439 new patients were included who were divided into the same prognostic groups as in the preceding study. RESULTS: In this study, the 6-month survival rates were 7% (for those with 20-25 points), 19% (for those with 26-30 points), 56% (for those with 31-35 points), 73% (for those with 36-40 points), and 90% (for those with 41-45 points), respectively (P < .0001). After regrouping, the 6-month survival rates were 14% (for those with 20-30 points), 56% (for those with 31-35 points), and 80% (for those with 36-45 points), respectively, in this study (P < .0001). CONCLUSIONS: In the current study, the difference in 6-month survival between the prognostic groups was found to be as significant as in the preceding study. Thus, this scoring system was considered valid to estimate survival of MSCC patients. The system could have been simplified by including only 3 instead of 5 prognostic groups. Cancer 2010. © 2010 American Cancer Society. [source] Regional differences in kelp-associated algal assemblages on temperate limestone reefs in south-western AustraliaDIVERSITY AND DISTRIBUTIONS, Issue 6 2003Thomas Wernberg Abstract.,Ecklonia radiata (C. Agardh) J. Agardh kelp beds , a characteristic feature of the nearshore environment along the south-west Australian coastline , contribute significantly to the coastal biodiversity in temperate Australia, yet, little is known about the organization of these macroalgal assemblages. By compiling existing and new data sets from habitat surveys, we have characterized and compared the structure of kelp-associated macroalgal assemblages in three regions (Marmion Lagoon, Hamelin Bay and the marine environment neighbouring the Fitzgerald River National Park) across more than 1000 kilometres of the south-west Australian coastline. 152 macroalgal taxa had been recognized within the three regions and this is in the range of species richness reported from other Australian and African kelp beds. The kelp-associated algal assemblages were regionally distinct, 66% of all taxa were only found in one region and only 17 taxa were found in all three regions. Adjacent regions shared an additional 13,15 taxa. The regional shifts in assemblage structure were evident in species composition of both canopy and understorey. The organization of assemblages followed a spatial hierarchy where differences in assemblage structure were larger among regions (hundreds of kilometres apart) than among sites within regions (kilometres apart) and differences among sites within region were larger than differences among quadrats within sites (metres apart). Despite this hierarchy each level of nesting contributed approximately the same to total variation in assemblage structure and these spatial patterns were stronger than temporal differences from seasons to 2,3 years. Our results suggest that local and small-scale processes contribute considerably to heterogeneity in macroalgal assemblages throughout south-western Australia, and, in particular, our results are consistent with E. radiata exerting a strong influence on macroalgal assemblage structure. Further, our study contradicts the existence of a general south-west Australian kelp assemblage, although a few species may form the core of E. radiata associations across regions. [source] Pollution and Cost in the Coke-Making Supply Chain in Shanxi Province, ChinaJOURNAL OF INDUSTRIAL ECOLOGY, Issue 3-4 2002Applying an Integrated System Model to Siting, Transportation Trade-Offs Summary An integrated system trade-off model has been developed to assess costs and pollution associated with transportation in the coke-making supply chain in Shanxi Province, China. A transportation-flow, cost-minimization solver is combined with models for calculating coke-making plant costs, estimating transportation costs from a geographic information system road and rail database, and aggregating coke-making capacity among plants. Model outputs of economic cost, nitrogen oxides (NOx) emissions, and transport distributions are visualized using an Internet-based graphic user interface. Data for the model were collected on survey trips to Shanxi Province as well as from secondary references and proxies. The modularity and extensibility of the system trade-off model facilitate introduction of new data sets in order to examine various planning scenarios. Scenarios of coke-making plant aggregation, rail infrastructure improvement, and technology transfer were evaluated using the model. Costs and pollution emissions can be reduced by enlarging coke-making plants near the rail stations and closing down other plants. Preferential minimization of transportation costs gives a lower total cost than simply minimizing plant costs. Therefore, policy makers should consider transportation costs when planning the reallocation of coke-making capacity in Shanxi Province. Increasing rail-transport capacity is less effective than aggregating plant capacity. On the other hand, transfer of low-pollution truck technology results in a large emission reduction, however, reflecting the importance of truck transportation in the Shanxi Province coke-making industry. [source] Correlates of Levels of Democracy in Latin America During the 1990sLATIN AMERICAN POLITICS AND SOCIETY, Issue 2 2006Cynthia McClintock ABSTRACT Does the conventional wisdom about the relationships between economic, cultural, and political party variables and democracy stand up in the Latin American experience of the 1990s? This study, utilizing new data sets for the region, finds that some traditional hypotheses are upheld better than others. It sustains the conventional wisdom that economic development, economic growth, democratic values, and (with a two-year lead) education correlate positively with the level of democracy. Surprisingly, however, neither social trust nor the number of political parties is significantly correlated with the level of democracy. The study suggests various possible explanations for the weak or nonexistent relationships for social trust and number of parties, in the hope that these surprising results will stimulate further research. [source] Artificial neural networks as statistical tools in epidemiological studies: analysis of risk factors for early infant wheezePAEDIATRIC & PERINATAL EPIDEMIOLOGY, Issue 6 2004Andrea Sherriff Summary Artificial neural networks (ANNs) are being used increasingly for the prediction of clinical outcomes and classification of disease phenotypes. A lack of understanding of the statistical principles underlying ANNs has led to widespread misuse of these tools in the biomedical arena. In this paper, the authors compare the performance of ANNs with that of conventional linear logistic regression models in an epidemiological study of infant wheeze. Data on the putative risk factors for infant wheeze have been obtained from a sample of 7318 infants taking part in the Avon Longitudinal Study of Parents and Children (ALSPAC). The data were analysed using logistic regression models and ANNs, and performance based on misclassification rates of a validation data set were compared. Misclassification rates in the training data set decreased as the complexity of the ANN increased: h = 0: 17.9%; h = 2: 16.2%; h = 5: 14.9%, and h = 10: 9.2%. However, the more complex models did not generalise well to new data sets drawn from the same population: validation data set misclassification rates: h = 0: 17.9%; h = 2: 19.6%; h = 5: 20.2% and h = 10: 22.9%. There is no evidence from this study that ANNs outperform conventional methods of analysing epidemiological data. Increasing the complexity of the models serves only to overfit the model to the data. It is important that a validation or test data set is used to assess the performance of highly complex ANNs to avoid overfitting. [source] The potential of L-band SAR for quantifying mangrove characteristics and change: case studies from the tropicsAQUATIC CONSERVATION: MARINE AND FRESHWATER ECOSYSTEMS, Issue 3 2007Richard M. Lucas Abstract 1.The Japan Aerospace Exploration Agency's (JAXA) Advanced Land Observing Satellite (ALOS) L-band Phased Array Synthetic Aperture Radar (PALSAR), launched successfully in January 2006, will provide new data sets for coastal ecosystems mapping and change monitoring at local to global scales. 2.To evaluate L-band capability for mangrove applications, data acquired by the NASA airborne SAR (AIRSAR) and Japanese Earth Resources Satellite (JERS-1 SAR) over sites in Australia, French Guiana and Malaysia were used to demonstrate benefits for mapping extent and zones, retrieving biomass and structural attributes (e.g. height), and detecting change. 3.The research indicates that mapping is most effective where mangroves border non-forested areas and where differences in structure, as a function of species, growth stage and biomass distributions, occur between zones. 4.Using L-band SAR, biomass can be retrieved up to ,100,140 Mg ha,1, although retrieval is complicated by a noticeable decrease in L-band backscattering coefficient within higher (,>200 Mg ha,1) biomass stands, particularly those with extensive prop root systems. 5.Change detection through multi-temporal comparison of data proved useful for mapping deforestation/regeneration and mangrove dynamics associated with changing patterns of sedimentation. 6.The research highlights the likely benefits and limitations of using ALOS PALSAR data and supports JAXA's Kyoto & Carbon (K&C) Initiative in promoting the use of these data for regional mangrove assessment. Copyright © 2007 John Wiley & Sons, Ltd. [source] | |||||||||||||||||||