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Equivalence
Kinds of Equivalence Terms modified by Equivalence Selected AbstractsAN EMPIRICAL ANALYSIS OF MEASUREMENT EQUIVALENCE WITH THE INDCOL MEASURE OF INDIVIDUALISM AND COLLECTIVISM: IMPLICATIONS FOR VALID CROSS-CULTURAL INFERENCEPERSONNEL PSYCHOLOGY, Issue 1 2006CHRISTOPHER ROBERT The INDCOL measure of individualism and collectivism (Singelis et al., 1995) has been used increasingly to test complex cross-cultural hypotheses. However, sample differences in translation, culture, organization, and response context might threaten the validity of cross-cultural inferences. We systematically explored the robustness of the INDCOL, for various statistical uses, in the face of those 4 threats. An analysis of measurement equivalence using multigroup mean and covariance structure analysis compared samples of INDCOL data from the United States, Singapore, and Korea. The INDCOL was robust with regard to the interpretability of correlations, whereas differences in culture and translation pose an important potential threat to the interpretability of mean-level analyses. Recommendations regarding the interpretation of the INDCOL and issues in the analysis of measurement equivalence in cross-cultural research are discussed. [source] PRESUPPOSITION PROJECTION AND LOGICAL EQUIVALENCE*PHILOSOPHICAL PERSPECTIVES, Issue 1 2008Daniel Rothschild First page of article [source] Current Evidence on the Unit Equivalence of Different Botulinum Neurotoxin A Formulations and Recommendations for Clinical Practice in DermatologyDERMATOLOGIC SURGERY, Issue 1 2009SYRUS KARSAI MD BACKGROUND The unit equivalence between the two main Botulinum neurotoxin A (BoNTA) preparations, Dysport (Ipsen Ltd., Slough, Berkshire, UK) and BOTOX (Allergan Inc., Irvine, CA), is a matter of discussion. The UK assay used to test Dysport is more sensitive than the U.S. assay used for BOTOX, resulting in a different efficacy per unit in both formulations. Ratios ranging from 6:1 to 1:1 can be found in the literature, but the more recently published literature suggests that 1 unit of BOTOX is equivalent to approximately 2 to 4 units of Dysport (ratio 2:1,4:1). OBJECTIVE Because the number of BoNTA treatments is constantly increasing, these differences warrant a systematic review of published evidence about the unit equivalence of UK and U.S. formulations. METHODS The review is based on a detailed literature research in all relevant databases (MEDLINE, PubMed, Cochrane Library, specialist textbooks). RESULTS The present review supports the recent assumption that dose ratios of less than 3:1 (e.g., 2.5:1 or even 2:1) between Dysport and BOTOX are probably more suitable. CONCLUSIONS The current evidence is still insufficient, and further investigation of lower dose ratios is recommended. [source] Characterization of Revenue EquivalenceECONOMETRICA, Issue 1 2009Birgit Heydenreich The property of an allocation rule to be implementable in dominant strategies by a unique payment scheme is called revenue equivalence. We give a characterization of revenue equivalence based on a graph theoretic interpretation of the incentive compatibility constraints. The characterization holds for any (possibly infinite) outcome space and many of the known results are immediate consequences. Moreover, revenue equivalence can be identified in cases where existing theorems are silent. [source] An accurate hybrid macro-element with linear displacementsINTERNATIONAL JOURNAL FOR NUMERICAL METHODS IN BIOMEDICAL ENGINEERING, Issue 1 2005Xiao-Ping Xie Abstract A hybrid stress quadrilateral macro-element HQM is proposed. Compatible linear displacements are used on its two triangular sub-domains, and a 5-parameter incomplete linear stress mode is suggested. Equivalence to another quadrilateral element HQ4 with compatible isoparametric bilinear displacements is proven. Due to elimination of stress parameters at the element level, the computational cost of HQM/HQ4 is as same as that of Q4. Numerical tests show that the element is accurate, insensitive to mesh distortions, and free from Poisson locking. Copyright © 2004 John Wiley & Sons, Ltd. [source] Measurement Equivalence of 360°-Assessment Data: Are different raters rating the same constructs?INTERNATIONAL JOURNAL OF SELECTION AND ASSESSMENT, Issue 3 2007Kelly M. Hannum This study uses data collected using a 360°-assessment instrument to investigate the structural equivalence of 360°-assessment ratings, according to rater type, controlling for organizational level. Data from 533 managers and their raters were employed in the study, which used multi-group structural equations modeling. Issues central to the implementation and use of 360°-assessment data are also considered within the context of current research and practice. [source] Construct Equivalence of Multiple-Choice and Constructed-Response Items: A Random Effects Synthesis of CorrelationsJOURNAL OF EDUCATIONAL MEASUREMENT, Issue 2 2003Michael C. Rodriguez A thorough search of the literature was conducted to locate empirical studies investigating the trait or construct equivalence of multiple-choice (MC) and constructed-response (CR) items. Of the 67 studies identified, 29 studies included 56 correlations between items in both formats. These 56 correlations were corrected for attenuation and synthesized to establish evidence for a common estimate of correlation (true-score correlations). The 56 disattenuated correlations were highly heterogeneous. A search for moderators to explain this variation uncovered the role of the design characteristics of test items used in the studies. When items are constructed in both formats using the same stem (stem equivalent), the mean correlation between the two formats approaches unity and is significantly higher than when using non-stem-equivalent items (particularly when using essay-type items). Construct equivalence, in part, appears to be a function of the item design method or the item writer's intent. [source] Bioequivalence of a new liquid formulation of ursodeoxycholic acid (Ursofalk suspension) and Ursofalk capsules measured by plasma pharmacokinetics and biliary enrichmentALIMENTARY PHARMACOLOGY & THERAPEUTICS, Issue 6 2005K. D. R. Setchell Summary Background:, Ursodeoxycholic acid is an approved therapy for hepatobiliary disorders but in infants and children compliance is compromised because it is formulated exclusively as capsules, or tablets. Aim:, To determine the pharmacokinetics and bioequivalence of a new liquid formulation of ursodeoxycholic acid (Ursofalk suspension) with a standard capsule (Ursofalk) in a randomized, unblinded, crossover designed study of 24 healthy adults. Methods:, Equivalence was based on single bolus oral plasma pharmacokinetics and biliary ursodeoxycholic acid enrichments after repeat doses. Biliary bile acid composition and hydrophobicity index were also compared. Ursodeoxycholic acid was measured in duodenal bile by high-performance liquid chromatography and in plasma by mass spectrometry. Results:, The mean percentage biliary ursodeoxycholic acid enrichment after administration of the suspension was not significantly different from that obtained with capsules (44.2 ± 11.7% vs. 46.9 ± 10.2%, respectively). The equivalence ratio was 0.94 (95% CI: 0.8,1.1), establishing bioequivalence between suspension and capsules. Both formulations reduced the biliary hydrophobicity index and no differences in bile acid composition were observed between formulations. The plasma pharmacokinetics of both formulations was similar and the tolerability of the suspension was excellent. Conclusions:, A new liquid formulation of ursodeoxycholic acid suitable for paediatric patients is pharmacologically bioequivalent to capsules when given as single, or repeated oral doses. [source] Equivalence of weak Dirichlet's principle, the method of weak solutions and Perron's method towards classical solutions of Dirichlet's problem for harmonic functionsMATHEMATISCHE NACHRICHTEN, Issue 4 2006Christian G. Simader Abstract For boundary data , , W1,2(G ) (where G , ,N is a bounded domain) it is an easy exercise to prove the existence of weak L2 -solutions to the Dirichlet problem ",u = 0 in G, u |,G = , |,G". By means of Weyl's Lemma it is readily seen that there is , , C,(G ), ,, = 0 and , = u a.e. in G . On the contrary it seems to be a complicated task even for this simple equation to prove continuity of , up to the boundary in a suitable domain if , , W1,2(G ) , C0(). The purpose of this paper is to present an elementary proof of that fact in (classical) Dirichlet domains. Here the method of weak solutions (resp. Dirichlet's principle) is equivalent to the classical approaches (Poincaré's "sweeping-out method", Perron's method). (© 2006 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim) [source] Equivalence between substrate-integrated (SIRW) rectangular waveguide short-circuit load and its equivalent rectangular waveguide short-circuit loadMICROWAVE AND OPTICAL TECHNOLOGY LETTERS, Issue 9 2006Wenquan Che Abstract Substrate integrated rectangular waveguide (SIRW) is an artificial rectangular waveguide (RW) constructed in planar substrate with two rows of periodic metallized posts or slots. In this letter, the equivalence formula between the locations of the corresponding short circuits by cylinder walls and by the solid wall was derived, based on the former width equivalence formula of the SIRW and its equivalent RW [(11)]]. The theoretical and simulation results are given for the SIRW short load and RW short load, good agreements have been observed. Such equivalences are convenient for the design of small waveguides, of millimeter wave, in a multilayer circuit structure, such as the LTCC etc. © 2006 Wiley Periodicals, Inc. Microwave Opt Technol Lett 48: 1694,1698, 2006; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/mop.21805 [source] Equivalence of hydroxyethyl starch HES 130/0.ACTA ANAESTHESIOLOGICA SCANDINAVICA, Issue 9 2003HES 200/0. Background:, Hydroxyethyl starch solutions (HES) are increasingly used for the compensation of surgical blood loss. The objective of this clinical trial was to compare a novel 6% HES 130/0.4 solution with a favourable pharmacological profile and a standard 6% HES 200/0.5 solution for maintenance of haemodynamic stability in major gynaecological surgery. Methods:, Sixty female patients aged 18,80 years undergoing major gynaecological surgery with indication for perioperative colloidal volume replacement were enrolled in this prospective, randomized double-blinded clinical study. The administration of study medication was dependent on individual requirements to maintain haemodynamic stability. The amount of study medication required from induction of anaesthesia until 6 h postoperatively served as the primary investigative parameter. Results:, The two one-sided test procedure by Westlake demonstrated equivalence of mean infused volumes between HES 130/0.4 and HES 200/0.5 during the study period (1224 ± 544 ml and 1389 ± 610 ml, respectively, P < 0.05). Perioperatively, haemodynamics did not differ significantly between treatment groups. While none of the mean values of coagulation parameters shifted outside the normal range, the degree of haemodilution revealed reduced haematocrit values in HES 200/0.5 treated patients at 6 h postoperatively (P < 0.05). Moreover, prothrombin time (PT) was higher and consequently international normalized ratio (INR) was lower at the same time point for patients who received HES 130/0.4 (P < 0.05). Conclusion:, This clinical trial demonstrated therapeutic equivalence of this novel low-substituted HES 130/0.4 solution and a standard HES 200/0.5 solution for perioperative volume replacement. Moreover, both HES preparations were equally well-tolerated and safe. [source] Equivalence of Three Allocation Currencies as Estimates of Reproductive Allocation and Somatic Cost of Reproduction in Pinguicula vulgarisPLANT BIOLOGY, Issue 4 2007M. Méndez Abstract: Which is the most appropriate currency (biomass, energy, water, or some mineral nutrient) for expressing resource allocation in plants has been repeatedly discussed. Researchers need to assess to which extent interindividual, interpopulational, or interspecific comparisons of resource allocation could be affected by the allocation currency chosen. The "currency issue" is relevant to at least three related aspects of resource allocation to reproduction: (a) reproductive allocation (RA), (b) size-dependence of reproductive allocation, and (c) somatic cost of reproduction (SCR). Empirical tests have mostly dealt with the first aspect only. We examined the equivalence of estimates for the three aspects above across three different allocation currencies (dry mass, N, P) in 11 populations of Pinguicula vulgaris. For RA we studied the equivalence of allocation currencies at three scales: among individuals of the same population, between populations of the same species, and among species. Equivalence of currencies in the ranking of RA for individuals within populations was high (Rs 0.43) and did not strongly decrease when comparing populations or species. Excepting for size-dependence of RA, ranking of RA, or SCR between populations was equivalent for biomass and N, but not for P. Our study gives two positive guidelines for empirical plant reproductive ecologists facing the "currency issue": (1) become increasingly concerned about the "currency issue" as you increase the scale of your comparison from individuals to populations to species, and (2) avoid estimating allocation in redundant currencies (biomass and N in our case) and choose preferentially "complementary" currencies that provide a broader view of allocation patterns (biomass and P in our case). [source] Behavioural Central Bank Loss Functions, Skewed Risks and Certainty EquivalenceTHE MANCHESTER SCHOOL, Issue 2003Ali Al-Nowaihi We set out to investigate the role of additive uncertainty under behaviourally plausible non-standard central bank loss functions on future inflation. Building on a substantial body of evidence in the economic psychology literature, we propose (i) period-by-period loss functions that are non-convex, i.e. displaying diminishing or non-increasing sensitivity to losses, and (ii) non-linear weighting of probabilities, hence departing from the expected utility paradigm. The main conclusion of the study is that if the additive uncertainty is caused by a non-normal distributed additive shock, for instance if the probability distribution of the shock is skewed, then with these departures from the quadratic function the principle of certainty equivalence does not hold anymore. [source] Equivalent Pharmacokinetics of Mycophenolate Mofetil in African-American and Caucasian Male and Female Stable Renal Allograft RecipientsAMERICAN JOURNAL OF TRANSPLANTATION, Issue 12 2003Mark D. Pescovitz African-American (AA) renal transplant recipients require higher doses of mycophenolate mofetil (MMF) than Caucasians. A hypothesized pharmacokinetic (PK) difference was tested in stable renal transplant recipients. Whole blood was collected before, and 20, 40 and 75 min, and 2, 3, 4, 6, 8 and 12 h after the MMF dose. Mycophenolic acid (MPA) and its glucuronide metabolite (MPAG) were analyzed using HPLC. Analysis of variance was performed for the primary end-points of dose-adjusted PK parameters AUC0,12 and Cmax of MPA using log-transformed values. Differences between races and genders were estimated: 90% confidence intervals (CI) were calculated. Back-transformation gave estimates of the race and gender ratio and their CI. Equivalence of the groups was determined if the 90% confidence limits were included in the interval (0.80, 1.25). The calculated PK parameters were comparable among the four subgroups (Caucasian, AA, Male, Female). The 90% CIs for the ratio of dose-adjusted AUC0,12 of MPA between races were between 89.7 and 112.9%. There were no race, gender or race-by-gender effects (p-values = 0.196) nor differences between diabetics and nondiabetics. This study demonstrates that dosing requirement for MMF in AA and Caucasians is unlikely to be related to different exposures to MPA. [source] Measurement Equivalence of Paper-and-Pencil and Internet Organisational Surveys: A Large Scale Examination in 16 CountriesAPPLIED PSYCHOLOGY, Issue 2 2009Alain De Beuckelaer In multinational surveys, mixed-mode administration modes (e.g. combining Internet and paper-and-pencil administration) are increasingly used. To date, no studies have investigated whether measurement equivalence exists between Internet data collection and data collection using the conventional paper-and-pencil method in organisational surveys which include a large number of countries. This paper examined the measurement equivalence of a truly global organisational survey across Internet and paper-and-pencil survey administrations. Data from an organisational survey in 16 countries (N = 52,461) across the globe were used to assess the measurement equivalence of an organisational climate measure within each country in which the survey was administered. The empirical data provided strong indications which support the measurement equivalence of the multi-item survey instrument across Internet and paper-and-pencil surveys in virtually all countries in which the survey was conducted. These findings suggest that merging data obtained through Internet and paper-and-pencil data administration in a particular country is legitimate as no evidence was found for differential effects across both modes of data collection. Dans les enquêtes internationales, les modalités d'administration mixtes, c'est-à-dire combinant les solution Internet et papier-crayon, sont de plus en plus utilisées. Jusqu'à présent, on ignore si le recueil de données par Internet est méthodologiquement équivalent au recueil traditionnel sur papier dans les enquêtes organisationnelles qui couvrent un grand nombre de pays. Dans cet article, on analyse l'analogie des mesures d'une enquête organisationnelle véritablement universelle utilisant à la fois une administration Internet et papier-crayon. Des données provenant de seize pays (N = 52,461) répartis sur l'ensemble de la planète ont été exploitées pour évaluer l'équivalence méthodologique d'une mesure du climat organisationnel dans chacun de ces pays. Les résultats empiriques sont en faveur de l'équivalence méthodologique de l'ensemble des items pour les recueils Internet et papier-crayon dans pratiquement tous les pays retenus pour l'enquête. Ces résultats montrent qu'il est légitime de traiter ensemble les données obtenues par Internet et par papier-crayon dans un même pays puisque rien ne nous permet d'affirmer l'existence d'un effet différentiel dû aux deux modes d'administration. [source] Therapeutic Equivalence , Clinical Issues and Statistical Methodology in Noninferiority TrialsBIOMETRICAL JOURNAL, Issue 1 2005Axel Munk This special issue on therapeutic equivalence contains a selection of 8 papers presented at the conference ,Therapeutic Equivalence , Clinical Issues and Statistical Methodology in Noninferiority Trials' held in Düsseldorf, December 12,13, 2003. The aim of this conference was to gather experts from academics, industry and regulatory agencies in the field of therapeutic equivalence, in particular of noninferiority trials. Originally initiated as a small workshop, it soon turned out that there is obviously strong need to discuss these challenging issues at a broader auditorium. Indeed, the feedback to this conference was overwhelming, finally more than 300 researchers participated. Hence the idea emerged to collect the results and discussions in a single journal issue. It took more than a year to finish it, and various activities in this rapidly developing area have been going on and were incorporated. We are very grateful to the Editors E. Brunner and M. Schumacher of the Biometrical Journal for their encouragement and support to publish this special issue on the occasion of this conference. Further, the technical assistance and expertise of G. Skipka and K. Thangavelu is gratefully acknowledged. We are also indebted to Peter Bauer and Stephen Senn for their discussions of the subsequent articles by Bristol, Freitag, Hauschke, Slacik-Erben, Hensen and Kaufmann, Hung, Wang and O'Neill, Lange and Freitag, Tsong and Zhang, Wellek, and last but not least we would like to thank Joachim Röhmel for his contribution to this special issue. Joachim Röhmel contributed significantly during the last three decades to various branches of biostatistical research, and in particular to the design and analysis of equivalence trials. The aim of this special issue is therefore twofold, it is also devoted to the occasion of Joachim Röhmel's retirement from BfArM in 2004. In the following we would briefly like to express our deep appreciation of his scientific work. (© 2005 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim) [source] Asymptotical Tests on the Equivalence, Substantial Difference and Non-inferiority Problems with Two ProportionsBIOMETRICAL JOURNAL, Issue 3 2004A. Martín Andrés Abstract Let d = p2 , p1 be the difference between two binomial proportions obtained from two independent trials. For parameter d, three pairs of hypothesis may be of interest: H1: d , , vs. K1: d > ,; H2: d ,, (,1, ,2) vs. K2: d , (,1, ,2); and H3: d , [,1, ,2] vs. K3: d ,, [,1, ,2], where Hi is the null hypothesis and Ki is the alternative hypothesis. These tests are useful in clinical trials, pharmacological and vaccine studies and in statistics generally. The three problems may be investigated by exact unconditional tests when the sample sizes are moderate. Otherwise, one should use approximate (or asymptotical) tests generally based on a Z -statistics like those suggested in the paper. The article defines a new procedure for testing H2 or H3, demonstrates that this is more powerful than tests based on confidence intervals (the classic TOST , two one sided tests , test), defines two corrections for continuity which reduce the liberality of the three tests, and selects the one that behaves better. The programs for executing the unconditional exact and asymptotic tests described in the paper can be loaded at http://www.ugr.es/~bioest/software.htm. (© 2004 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim) [source] The (Non-)Equivalence of Input and Output Taxes Under MonopolyBULLETIN OF ECONOMIC RESEARCH, Issue 3 2001Thorsten Bay, r-Upmann The author argues that a government taxing a polluting monopoly by means of levies on output and inputs can implement the first-best allocation through a continuum of tax profiles. Using this degree of freedom in the tax system, the government is, in general, able to transfer income from the firm to the public sector, so that the additional tax rate acts as a non-distorting tax on profits. This transfer , and therefore public revenue , is the higher, the lower (higher) the input taxes are, and correspondingly the higher (lower) the output tax is, provided that the production function exhibits decreasing (increasing) returns to scale. [source] Chelated Heteroatoms in Polyoxometalates and the Topological Equivalence of {CoIII(en)} to Type II cis-Dioxometal Centers.CHEMINFORM, Issue 12 2006-OH)2Co(en)}{PW10O37Co (en)}2]8-, Structure of [{Co(en)(, Synthesis, [K@{Co(en)WO4}{WO(H2O)} (PW9O34)2]12- . Abstract ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 200 leading journals. To access a ChemInform Abstract, please click on HTML or PDF. [source] A Multicenter Comparison of Tap Water versus Sterile Saline for Wound IrrigationACADEMIC EMERGENCY MEDICINE, Issue 5 2007Ronald M. Moscati MD ObjectivesTo compare wound infection rates for irrigation with tap water versus sterile saline before closure of wounds in the emergency department. MethodsThe study was a multicenter, prospective, randomized trial conducted at two Level 1 urban hospitals and a suburban community hospital. Subjects were a convenience sample of adults presenting with acute simple lacerations requiring sutures or staples. Subjects were randomized to irrigation in a sink with tap water or with normal saline using a sterile syringe. Wounds were closed in the standard fashion. Subjects were asked to return to the emergency department for suture removal. Those who did not return were contacted by telephone. Wounds were considered infected if there was early removal of sutures or staples, if there was irrigation and drainage of the wound, or if the subject needed to be placed on antibiotics. Equivalence of the groups was met if there was less than a doubling of the infection rate. ResultsA total of 715 subjects were enrolled in the study. Follow-up data were obtained on 634 (88%) of enrolled subjects. Twelve (4%) of the 300 subjects in the tap water group had wound infections, compared with 11 (3.3%) of the 334 subjects in the saline group. The relative risk was 1.21 (95% confidence interval = 0.5 to 2.7). ConclusionsEquivalent rates of wound infection were found using either irrigant. The results of this multicenter trial evaluating tap water as an irrigant agree with those from previous single institution trials. [source] Sample Size Determination for Establishing Equivalence/Noninferiority via Ratio of Two Proportions in Matched,Pair DesignBIOMETRICS, Issue 4 2002Man-Lai Tang Summary. In this article, we propose approximate sample size formulas for establishing equivalence or noninferiority of two treatments in match-pairs design. Using the ratio of two proportions as the equivalence measure, we derive sample size formulas based on a score statistic for two types of analyses: hypothesis testing and confidence interval estimation. Depending on the purpose of a study, these formulas can be used to provide a sample size estimate that guarantees a prespecified power of a hypothesis test at a certain significance level or controls the width of a confidence interval with a certain confidence level. Our empirical results confirm that these score methods are reliable in terms of true size, coverage probability, and skewness. A liver scan detection study is used to illustrate the proposed methods. [source] Equivalences between refractive index and equilibrium water content of conventional and silicone hydrogel soft contact lenses from automated and manual refractometry,JOURNAL OF BIOMEDICAL MATERIALS RESEARCH, Issue 1 2007José M. González-Méijome Abstract Purpose The purpose of the present study was to develop mathematical relationships that allow obtaining equilibrium water content and refractive index of conventional and silicone hydrogel soft contact lenses from refractive index measures obtained with automated refractometry or equilibrium water content measures derived from manual refractometry, respectively. Methods Twelve HEMA-based hydrogels of different hydration and four siloxane-based polymers were assayed. A manual refractometer and a digital refractometer were used. Polynomial models obtained from the sucrose curves of equilibrium water content against refractive index and vice-versa were used either considering the whole range of sucrose concentrations (16,100% equilibrium water content) or a range confined to the equilibrium water content of current soft contact lenses (,20,80% equilibrium water content). Results Values of equilibrium water content measured with the Atago N-2E and those derived from the refractive index measurement with CLR 12,70 by the applications of sucrose-based models displayed a strong linear correlation (r2 = 0.978). The same correlations were obtained when the models are applied to obtain refractive index values from the Atago N-2E and compared with those (values) given by the CLR 12,70 (r2 = 0.978). No significantly different results are obtained between models derived from the whole range of the sucrose solution or the model limited to the normal range of soft contact lens hydration. Conclusions Present results will have implications for future experimental and clinical research regarding normal hydration and dehydration experiments with hydrogel polymers, and particularly in the field of contact lenses. © 2006 Wiley Periodicals, Inc. J Biomed Mater Res Part B: Appl Biomater, 2007 [source] Making White: Constructing Race in a South African High SchoolCURRICULUM INQUIRY, Issue 1 2002Nadine Dolby As a social and cultural phenomenon, race is continually remade within changing circumstances and is constructed and located, in part, in institutions' pedagogical practices and discourses. In this article I examine how the administration of a multiracial, working-class high school in Durban, South Africa produces "white" in an era of political and social transition. As the population of Fernwood High School (a pseudonym) shifts from majority white working class to black working class, the school administration strives to reposition the school as "white," despite its predominantly black student population. This whiteness is not only a carryover from the apartheid era, but is actively produced within a new set of circumstances. Using the discourses and practices of sports and standards, the school administration attempts to create a whiteness that separates the school from the newly democratic nation-state of South Africa. Despite students' and some staff's general complacency and outright resistance, rugby and athletics are heralded as critical nodes of the school's "white" identity, connecting the school to other, local white schools, and disconnecting it from black schools. Dress standards function in a similar manner, creating an imagined equivalence between Fernwood and other white schools in Durban (and elite schools around the world), and disassociating Fernwood from black schools in South Africa and the "third world" writ large. This pedagogy of whiteness forms the core of the administration's relationship with Fernwood students, and maps how race is remade within a changing national context. [source] Measurement Equivalence Using Generalizability Theory: An Examination of Manufacturing Flexibility DimensionsDECISION SCIENCES, Issue 4 2008Manoj K. Malhotra ABSTRACT As the field of decision sciences in general and operations management in particular has matured from theory building to theory testing over the past two decades, it has witnessed an explosion in empirical research. Much of this work is anchored in survey-based methodologies in which data are collected from the field in the form of scale items that are then analyzed to measure latent unobservable constructs. It is important to assess the invariance of scales across groups in order to reach valid, scientifically sound conclusions. Because studies have often been conducted in the field of decision sciences with small sample sizes, it further exacerbates the problem of reaching incorrect conclusions. Generalizability theory can more effectively test for measurement equivalence in the presence of small sample sizes than the confirmatory factor analysis (CFA) tests that have been conventionally used for assessing measurement equivalency across groups. Consequently, we introduce and explain the generalizability theory (G-theory) in this article to examine measurement equivalence of 24 manufacturing flexibility dimension scales that have been published in prior literature and also compare and contrast G-theory with CFA. We show that all the manufacturing flexibility scales tested in this study were invariant across the three industry SIC groups from which data were collected. We strongly recommend that G-theory should always be used for determining measurement equivalence in empirical survey-based studies. In addition, because using G-theory alone does not always reveal the complete picture, CFA techniques for establishing measurement equivalence should also be invoked when sample sizes are large enough to do so. Implications of G-theory for practice and its future use in operations management and decision sciences research are also presented. [source] An Empirical Study of Equivalence Judgments vs.DECISION SCIENCES, Issue 2 2001Ratio Judgments in Decision Analysis Abstract Two commonly used elicitation modes on strength of preference, equivalence and ratio judgments, were compared in an experiment. The result from the experiment showed that ratio judgments were less effective than equivalence judgments. Based on an iterative design for eliciting multiattribute preference structures, equivalence judgments outperformed ratio judgments in estimating single-attribute measurable value functions, while being nearly more effective than ratio judgments in assessing multiattribute preference structures. The implications of the results from the experiment are that multiattribute decision-making techniques should take advantage of the decision maker's inclination of making effective equivalence trade-off judgments, and that useful techniques should be devised to incorporate different commonly used techniques, such as multiattribute utility theory and the Analytic Hierarchy Process, to elicit and consolidate equivalence trade-off judgments. [source] Current Evidence on the Unit Equivalence of Different Botulinum Neurotoxin A Formulations and Recommendations for Clinical Practice in DermatologyDERMATOLOGIC SURGERY, Issue 1 2009SYRUS KARSAI MD BACKGROUND The unit equivalence between the two main Botulinum neurotoxin A (BoNTA) preparations, Dysport (Ipsen Ltd., Slough, Berkshire, UK) and BOTOX (Allergan Inc., Irvine, CA), is a matter of discussion. The UK assay used to test Dysport is more sensitive than the U.S. assay used for BOTOX, resulting in a different efficacy per unit in both formulations. Ratios ranging from 6:1 to 1:1 can be found in the literature, but the more recently published literature suggests that 1 unit of BOTOX is equivalent to approximately 2 to 4 units of Dysport (ratio 2:1,4:1). OBJECTIVE Because the number of BoNTA treatments is constantly increasing, these differences warrant a systematic review of published evidence about the unit equivalence of UK and U.S. formulations. METHODS The review is based on a detailed literature research in all relevant databases (MEDLINE, PubMed, Cochrane Library, specialist textbooks). RESULTS The present review supports the recent assumption that dose ratios of less than 3:1 (e.g., 2.5:1 or even 2:1) between Dysport and BOTOX are probably more suitable. CONCLUSIONS The current evidence is still insufficient, and further investigation of lower dose ratios is recommended. [source] Moxonidine improves glycaemic control in mildly hypertensive, overweight patients: a comparison with metforminDIABETES OBESITY & METABOLISM, Issue 4 2006Irina Chazova Aim:, To compare the effects of moxonidine and metformin on glycaemic control in patients with impaired glucose tolerance and signs of the metabolic syndrome. Methods:, A multicentre, prospective, randomized, open-label study design was adopted with blinded endpoint evaluation. Patients ,40 years old, with impaired glucose tolerance (or diabetes mellitus treated with diet alone) and a body mass index (BMI) of at least 27 kg/m2 were treated twice daily with moxonidine 0.2 mg or metformin 500 mg for 16 weeks. Oral glucose tolerance test (OGTT) was performed at baseline and end-of-study; plasma insulin and plasma glucose levels were measured at 0, 60, 120 and 180 min after administration. Results:, With regard to effects on insulin [mean area under the curve (AUC) for insulin], the primary efficacy endpoint of the study, both drugs did not show equivalence. On the contrary, in the per protocol (PP) population, moxonidine statistically significantly (p = 0.025) decreased the AUC for insulin from baseline in the PP population; for metformin, the treatment effect on insulin was a small, net increase resulting in a statistically significant between-group difference of 16.2% (95% CI = 0.1,35.0). The change in mean insulin AUC was most marked in the subgroup of patients with higher sympathetic activity (heart rate >80 bpm). Mean fasting plasma glucose (FPG) levels and HbA1c levels were largely unchanged by moxonidine treatment but significantly decreased by metformin treatment. The difference between the groups was 14.7% (p = 0.0523) in the intent-to-treat (ITT) sample. By study end, both treatments had significantly increased the Matsuda Insulin Sensitivity Index (ISI) from baseline to a comparable extent: moxonidine by reducing plasma insulin after a glucose challenge, metformin by reducing FPG. BMI fell significantly in both groups and blood pressure normalized; both drugs were well tolerated. Conclusions:, Moxonidine improved insulin sensitivity in response to glucose challenge in patients with evidence of metabolic syndrome. This improvement resulted from a reduction in plasma insulin levels and was most marked in patients with high sympathetic drive at baseline. By enhancing insulin sensitivity, moxonidine treatment may help prevent the development of diabetes and thereby ameliorate the risk for cardiovascular disease. [source] Defining and measuring braiding intensityEARTH SURFACE PROCESSES AND LANDFORMS, Issue 14 2008Roey Egozi Abstract Geomorphological studies of braided rivers still lack a consistent measurement of the complexity of the braided pattern. Several simple indices have been proposed and two (channel count and total sinuosity) are the most commonly applied. For none of these indices has there been an assessment of the sampling requirements and there has been no systematic study of the equivalence of the indices to each other and their sensitivity to river stage. Resolution of these issues is essential for progress in studies of braided morphology and dynamics at the scale of the channel network. A series of experiments was run using small-scale physical models of braided rivers in a 3 m , 20 m flume. Sampling criteria for braid indices and their comparability were assessed using constant-discharge experiments. Sample hydrographs were run to assess the effect of flow variability. Reach lengths of at least 10 times the average wetted width are needed to measure braid indices with precision of the order of 20% of the mean. Inherent variability in channel pattern makes it difficult to achieve greater precision. Channel count indices need a minimum of 10 cross-sections spaced no further apart than the average wetted width of the river. Several of the braid indices, including total sinuosity, give very similar numerical values but they differ substantially from channel-count index values. Consequently, functional relationships between channel pattern and, for example, discharge, are sensitive to the choice of braid index. Braid indices are sensitive to river stage and the highest values typically occur below peak flows of a diurnal (melt-water) hydrograph in pro-glacial rivers. There is no general relationship with stage that would allow data from rivers at different relative stage to be compared. At present, channel count indices give the best combination of rapid measurement, precision, and range of sources from which measurements can be reliably made. They can also be related directly to bar theory for braided pattern development. Copyright © 2008 John Wiley & Sons, Ltd. [source] A Comparison of Echocardiographic Techniques in Determination of Arterial Elasticity in the Pediatric PopulationECHOCARDIOGRAPHY, Issue 5 2009Michael Fahey M.D. Background: Many methods are used to measure arterial elasticity in children using echocardiography. There is no data to support the equivalence of the different techniques. The goal of this study was to evaluate the reproducibility of several techniques used to measure arterial elasticity using echocardiography. Methods: Aortic distension in two different sites (arterial distension) through the cardiac cycle was measured by (four) two-dimensional (2D) and M-mode echocardiographic techniques in 20 children without significant structural heart disease. These measurements combined with noninvasive blood pressure measurements were used to calculate arterial elastic indices. Arterial elasticity was expressed in terms of distensibility and stiffness. Data were collected by two sonographers and interpreted by two reviewers. Paired Student's t-test and Pitman's test for equality of variance for correlated observations were used to detect differences between different sonographers, different reviewers, and different techniques. Results: No significant difference in the measured elasticity between sonographers or reviewers was observed. There was a somewhat increased variance in two of the four techniques evaluated. There was no significant difference in elasticity measured using different techniques to evaluate the same arterial site, although a significantly decreased elasticity was noted from measurements taken in the proximal ascending aorta as compared with the distal ascending aorta. Conclusions: Many echocardiographic techniques produce reproducible measurements of arterial elasticity. There may be intrinsic differences in arterial elasticity between different segments of the ascending aorta, which have not been previously described in children with normal cardiac anatomy. Comparisons of data from separate studies must take these differences into account. [source] A general framework for neutral models of community dynamicsECOLOGY LETTERS, Issue 12 2009Omri Allouche Abstract Neutral models of community dynamics are a powerful tool for ecological research, but their applications are currently limited to unrealistically simple types of dynamics and ignore much of the complexity that characterize natural ecosystems. Here, we present a new analytical framework for neutral models that unifies existing models of neutral communities and extends the applicability of existing models to a much wider spectrum of ecological phenomena. The new framework extends the concept of neutrality to fitness equivalence and in spite of its simplicity explains a wide spectrum of empirical patterns of species diversity including positive, negative and unimodal productivity,diversity relationships; gradual and highly delayed declines in species diversity with habitat loss; and positive and negative responses of species diversity to habitat heterogeneity. Surprisingly, the abundance distribution in all of these cases is given by the dispersal limited multinomial (DLM), the abundance distribution in Hubbell's zero-sum model, showing DLM's robustness and demonstrating that it cannot be used to infer the underlying community dynamics. These results support the hypothesis that ecological communities are regulated by a limited set of fundamental mechanisms much simpler than could be expected from their immense complexity. Ecology Letters (2009) 12: 1287,1297 [source] | |||||||||||||||||||||||||||||||||||||||||||