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Different Classifications (different + classification)
Selected AbstractsDecision-making method using a visual approach for cluster analysis problems; indicative classification algorithms and grouping scopeEXPERT SYSTEMS, Issue 3 2007Ran M. Bittmann Abstract: Currently, classifying samples into a fixed number of clusters (i.e. supervised cluster analysis) as well as unsupervised cluster analysis are limited in their ability to support ,cross-algorithms' analysis. It is well known that each cluster analysis algorithm yields different results (i.e. a different classification); even running the same algorithm with two different similarity measures commonly yields different results. Researchers usually choose the preferred algorithm and similarity measure according to analysis objectives and data set features, but they have neither a formal method nor tool that supports comparisons and evaluations of the different classifications that result from the diverse algorithms. Current research development and prototype decisions support a methodology based upon formal quantitative measures and a visual approach, enabling presentation, comparison and evaluation of multiple classification suggestions resulting from diverse algorithms. This methodology and tool were used in two basic scenarios: (I) a classification problem in which a ,true result' is known, using the Fisher iris data set; (II) a classification problem in which there is no ,true result' to compare with. In this case, we used a small data set from a user profile study (a study that tries to relate users to a set of stereotypes based on sociological aspects and interests). In each scenario, ten diverse algorithms were executed. The suggested methodology and decision support system produced a cross-algorithms presentation; all ten resultant classifications are presented together in a ,Tetris-like' format. Each column represents a specific classification algorithm, each line represents a specific sample, and formal quantitative measures analyse the ,Tetris blocks', arranging them according to their best structures, i.e. best classification. [source] Localization of Accessory Pathways in the Wolff-Parkinson-White Pattern,Physician Versus Computer Interpretation of the Same AlgorithmPACING AND CLINICAL ELECTROPHYSIOLOGY, Issue 8 2007ANDREW D. McGAVIGAN M.D., M.R.C.P. Background: There are several published algorithms for the prediction of accessory pathway (AP) location in the Wolff-Parkinson-White syndrome from the 12-lead electrocardiogram (ECG). Most depend on stepwise criteria, and minor disagreements between observers over QRS transition point or delta wave axis may lead to different classification of pathway location. We compared the utility of a computerized program in identifying pathway location from the ECG using the algorithm published by Fitzpatrick and coworkers3 against physician assessment with the same algorithm. Methods: Thirty-one 12-lead ECGs with an overt preexcitation pattern were examined by three physicians and AP localized to one of eight anatomical sites using the Fitzpatrick algorithm, with disagreements resolved by consensus. Similarly, pathway location was determined by the Glasgow ECG program with the Fitzpatrick algorithm incorporated into its logic. Results: The agreement between each physician and their consensus was 28/31, 29/31, and 29/31. Similarly, assessment by the Glasgow program produced agreement with the physician consensus in 29/31 cases. Of the 24 patients who underwent radiofrequency ablation, the program localized the pathway to the true or adjacent annular region in 20, compared to 20/24 by physician assessment of the algorithm, producing a similar predictive accuracy to published data. Conclusion: This study has shown that incorporation of the Fitzpatrick algorithm for AP location into a widely used computer program results in the same level of performance as that of experienced physicians and may be useful in clinical practice as an aid to referral for electrophysiological study and ablation. [source] Decision-making method using a visual approach for cluster analysis problems; indicative classification algorithms and grouping scopeEXPERT SYSTEMS, Issue 3 2007Ran M. Bittmann Abstract: Currently, classifying samples into a fixed number of clusters (i.e. supervised cluster analysis) as well as unsupervised cluster analysis are limited in their ability to support ,cross-algorithms' analysis. It is well known that each cluster analysis algorithm yields different results (i.e. a different classification); even running the same algorithm with two different similarity measures commonly yields different results. Researchers usually choose the preferred algorithm and similarity measure according to analysis objectives and data set features, but they have neither a formal method nor tool that supports comparisons and evaluations of the different classifications that result from the diverse algorithms. Current research development and prototype decisions support a methodology based upon formal quantitative measures and a visual approach, enabling presentation, comparison and evaluation of multiple classification suggestions resulting from diverse algorithms. This methodology and tool were used in two basic scenarios: (I) a classification problem in which a ,true result' is known, using the Fisher iris data set; (II) a classification problem in which there is no ,true result' to compare with. In this case, we used a small data set from a user profile study (a study that tries to relate users to a set of stereotypes based on sociological aspects and interests). In each scenario, ten diverse algorithms were executed. The suggested methodology and decision support system produced a cross-algorithms presentation; all ten resultant classifications are presented together in a ,Tetris-like' format. Each column represents a specific classification algorithm, each line represents a specific sample, and formal quantitative measures analyse the ,Tetris blocks', arranging them according to their best structures, i.e. best classification. [source] Summer rain fall duration and its diurnal cycle over the US Great PlainsINTERNATIONAL JOURNAL OF CLIMATOLOGY, Issue 10 2009Haoming Chen Abstract By diagnosing the hourly station rain gauge data set for the 1981,1999 periods, it is found that the rainfall diurnal cycle is closely related to its duration during summer (June,August) over the Great Plains [(GP), 100,90°W, 35,45°N]. Short-duration rainfall events (an event of 1 h in duration) occur more frequently in summer, and they tend to have two diurnal maxima over the GP, with one in the early morning [0400,0600 local solar time, (LST)] and the other in the afternoon (1500,1700 LST). Long-duration rainfall events (an event that lasts longer than 3 h) contribute more to the precipitation amount, and they tend to peak from the midnight to early morning (000,0600 LST). This contrast in the diurnal cycle of different classifications of precipitation events over the GP reflects the differences in the convective processes at night and during late afternoon. Copyright © 2008 Royal Meteorological Society [source] Consolidating the Gains Made in Diplomacy Studies: A Taxonomy,INTERNATIONAL STUDIES PERSPECTIVES, Issue 1 2008Stuart Murray Since the end of the Cold War, the scope and study of diplomacy has expanded. In the modern diplomatic environment, novel terms such as pipeline diplomacy, coercive diplomacy, diplomacy by sanction and citizen diplomacy are common, alongside the more traditional view of diplomacy as state-to-state activity, monopolized by professional, official diplomats. With such a broad range of views, the scholar can become confused as to what actually constitutes modern diplomacy? In this article, it is argued that the disparity of views in the diplomacy studies field must be classified and consolidated before the enhanced role of diplomacy in the twenty-first century can be better understood. In this article, three different classifications or schools of diplomatic thought are introduced and constructed: the Traditional School, the Nascent School, and the Innovative School. [source] The European Policy for the Development of an Information Society: the Right Path?,JCMS: JOURNAL OF COMMON MARKET STUDIES, Issue 4 2008JOSÉ LUIS GÓMEZ-BARROSO The end of 2005 marked the closure of one stage in the European strategy for the promotion of the information society (the eEurope programme) and the start of the next one (i2010). This seems to be a good time for assessing the results achieved to date by the community policy in this area and analysing whether the correct approach has been adopted. Despite the satisfaction shown in certain official appraisals, the picture resulting from consulting different classifications globally measuring the adaptation of countries to the information society is not that optimistic. Only the European Union leaders in this field (the Nordic countries) have improved their positions, broadening the gap with the rest: western European countries have lost ground (or at least have not improved) in the rankings, the southern countries do not seem to have corrected their deficiencies and the indices for the new Member States have not evolved as expected or have even deteriorated in some cases. Even though becoming one of the most competitive and dynamic knowledge-based economies in the world was the first Leitmotiv of the Lisbon strategy, the interpretation of the documents connected to the definition of the new stage in the strategy led to doubts over whether the European Union has a clear notion on the course of action to take in order to make progress on the information society a matter of priority. [source] A simple system for biofilm potential monitoring in drinking waterJOURNAL OF BASIC MICROBIOLOGY, Issue 1 2006Eric Delahaye Dr. SAGEP-EAU DE PARIS produces drinking water for the city of Paris (France). In order to supply a high quality water, one of the main SAGEP's concerns is to monitor the Biofilm Formation Potentials of the produced drinking waters. Biofilm incubators were installed at the outlet of three Water Treatment Plants (WTP). These incubators allowed biofilm formation and quantification in terms of Fixed Total Organic Carbon (FTOC), fixed culturable bacteria (HPC-R2A) and fixed total bacteria. During this study, quantitative differences appeared between the biofilms formed at the outlet of the three WTPs, leading to different classifications of the Biofilm Formation Potentials of the three produced waters, depending on the used parameter for biofilms quantification. This observation underlined the necessity of a multi-parametric approach for the study of biofilms. More generally, our results validated the use of these sturdy stainless steel incubators, highly adapted to industrial field conditions, for the monitoring of Biofilm Formation Potentials in drinking water networks. (© 2006 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim) [source] Classification and management of chronic sialadenitis of the parotid glandJOURNAL OF ORAL REHABILITATION, Issue 1 2009S. WANG Summary, Saliva has numerous oral functions and multiple functions in relation to digestion in the upper gastrointestinal tract. Chronic salivary hypofunction can lead to severe adverse health outcomes. Chronic sialadenitis is one of the major conditions that can cause salivary hypofunction. A correct diagnosis and management of chronic sialadenitis is essential for the recovery of salivary hypofunction. Chronic sialadenitis of the parotid gland is often seen in the clinic, sometimes also referred to as recurrent pyogenic parotitis, recurrent parotitis, non-obstructive parotitis, sialadenitis or obstructive parotitis, among other terms. The literature describes several different classifications and denominations for chronic sialadenitis of the parotid gland. These various classifications and denominations complicate the definition and diagnostic criteria, and if chronic sialadenitis of the parotid gland can develop into Sjogren's syndrome remains unclear. Treatment of this condition is also a challenging problem. Here, we review the presented classification and denomination of chronic sialadenitis of the parotid gland, proposing a classification based on the disease entities identified in a long-term follow-up investigation, and discuss the treatment principles for the condition. [source] Stratified resampling of phytosociological databases: some strategies for obtaining more representative data sets for classification studiesJOURNAL OF VEGETATION SCIENCE, Issue 4 2005Ilona Knollová Abstract Question: The heterogeneous origin of the data in large phytosociological databases may seriously influence the results of their analysis. Therefore we propose some strategies for stratified resampling of such databases, which may improve the representativeness of the data. We also explore the effects of different resampling options on vegetation classification. Methods: We used 6050 plot samples (relevés) of mesic grasslands from the Czech Republic. We stratified this database using (1) geographical stratification in a grid; (2) habitat stratification created by an overlay of digital maps in GIS; (3) habitat stratification with strata defined by traditional phytosociological associations; (4) habitat stratification by numerical classification and (5) habitat stratification by Ellenberg indicator values. Each time we resampled the database, taking equal numbers of relevés per stratum. We then carried out cluster analyses for the resampled data sets and compared the resulting classifications using a newly developed procedure. Results: Random resampling of the initial data set and geographically stratified resampling resulted in similar classifications. By contrast, classifications of the resampled data sets that were based on habitat stratifications (2,5) differed from each other and from the initial data set. Stratification 2 resulted in classifications that strongly reflected environmental factors with a coarse grain of spatial heterogeneity (e.g. macroclimate), whereas stratification 5 resulted in classifications emphasizing fine-grained factors (e.g. soil nutrient status). Stratification 3 led to the most deviating results, possibly due to the subjective nature of the traditional phytosociological classifications. Conclusions: Stratified resampling may increase the representativeness of phytosociological data sets, but different types of stratification may result in different classifications. No single resampling strategy is optimal or superior: the appropriate stratification method must be selected according to the objectives of specific studies. [source] The role of fat mass index in determining obesityAMERICAN JOURNAL OF HUMAN BIOLOGY, Issue 5 2010Gerson Peltz Objectives: The objective of this study is to compare body mass index (BMI), percent body fat (PBF), and fat mass index (FMI) and to investigate the accuracy of FMI as a convenient tool for assessing obesity. Design: Anthropometric measurements and bioelectrical impedance analyses were performed on 538 Mexican Americans (373 women and 165 men). Correlations between BMI and PBF and between FMI and PBF were investigated. The percentage of persons misclassified as obese using different classifications was calculated. Multiple linear regression analysis was performed to generate predictive models of FMI for males and females separately. Results: BMI and PBF were correlated in men (, = 0.877; P < 0.0001) and women (, = 0.966; P < 0.0001); however, 20 and 67.2% of the men and 9.2 and 84.2% of women, classified as normal weight and overweight by BMI, respectively, were diagnosed as obese by PBF. FMI and PBF were also correlated in men (, = 0.975; P < 0.0001) and women (, = 0.992; P < 0.0001). Four percent of the men classified as normal weight and 65.5% classified as overweight by BMI were obese by FMI, while 71.3% of women classified as overweight by BMI were obese by FMI. Misclassification of obesity between FMI and PBF categories was observed in 5.4% of men and 7.8% of women. Conclusions: The discrepancy observed between BMI and PBF reflects a limitation of BMI. Conversely, FMI accurately assessed obesity in our study of Mexican Americans, but further studies are necessary to confirm our findings in different ethnic groups. Am. J. Hum. Biol. 22:639,947, 2010. © 2010 Wiley-Liss, Inc. [source] A whole genome association analysis identifies loci associated with Mycobacterium avium subsp. paratuberculosis infection status in US holstein cattleANIMAL GENETICS, Issue 5 2009M. Settles Summary The purpose of this study was to identify loci associated with Mycobacterium avium subspecies paratuberculosis (Map) infection status in US Holsteins using the Illumina BovineSNP50 BeadChip whole genome single nucleotide polymorphism (SNP) assay. Two hundred forty-five cows from dairies in New York, Pennsylvania and Vermont enrolled in longitudinal herd studies between January 1999 and November 2007 were assessed for the presence of Map in both faecal and tissue samples. An animal was considered tissue infected if any sample contained at least one colony forming unit of Map per gram of tissue (CFU/g) and the same definition was employed for faecal samples. Each animal was genotyped with the Illumina BovineSNP50 BeadChip and after quality assurance filtering, 218 animals and 45 683 SNPs remained. We sought to identify loci associated with four different case/control classifications: presence of Map in the tissue, presence of Map in faeces, presence of Map in both tissue and faeces and presence of Map in tissue but not faeces. A case,control genome wide association study was conducted to test the four different classifications of Map infection status (cases) when compared with a Map -negative control group (control). Regions on chromosomes 1, 5, 7, 8, 16, 21 and 23 were identified with moderate significance (P < 5 × 10,5). Two regions, one on chromosome 3 (near EDN2) and another on chromosome 9 (no positional gene candidates), were identified with a high level of association to the presence of Map in tissue and both tissue and faeces respectively (P < 5 × 10,7, genome-wide Bonferonni P < 0.05). [source] On the Other "Phylogenetic Systematics"CLADISTICS, Issue 3 2000Kevin C. Nixon De Queiroz and Gauthier, in a serial paper, argue that biological taxonomy is in a sad state, because taxonomists harbor "widely held belief" systems that are archaic and insufficient for modern classification, and that the bulk of practicing taxonomists are essentialists. Their paper argues for the scrapping of the current system of nomenclature, but fails to provide specific rules for the new "Phylogenetic Systematics",instead we have been presented with a vague and sketchy manifesto based upon the assertion that "clades are individuals" and therefore must be pointed at with proper names, rather than diagnosed by synapomorphies. They claim greater stability for "node pointing," yet even their own examples show that the opposite is true, and their node pointing system is only more stable in a purely metaphysical sense detached from characters, evidence, usage of names, and composition of groups. We will show that the node pointing system is actually far LESS stable than the existing Linnaean System when stability is measured by the rational method of determining the net change in taxa (species) included in a particular group under different classifications. [source] | |||||||||||||||||||