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Measurement Approach (measurement + approach)
Selected AbstractsSub-Optimality of Income Statement-Based Methods for Measuring Operational Risk under Basel II: Empirical Evidence from Spanish BanksFINANCIAL MARKETS, INSTITUTIONS & INSTRUMENTS, Issue 4 2007Enrique Bonsón The New Basel Capital Accord (Basel II) was created with the intention of establishing a framework in which financial entities can manage their risks in a more detailed and efficient way. Within this general reform movement, Operational Risk emerges as a fundamental variable. OR can be managed by three alternative methods: the Basic Indicator Approach, Standard Approach and Advanced Measurement Approach. The choice of which method to adopt has become of supreme interest for senior banking managers. This study analyzes the exactitude of the underlying implicit hypotheses that support each method, distinguishing between income statement based methods and the management accounting based method. In the present study the non-optimum character of the two Income Statement-based methods is empirically confirmed, in the light of the data provided by Spanish financial entities. [source] A NEW METHOD FOR STUDYING THE EXTENT, STABILITY, AND PREDICTORS OF INDIVIDUAL SPECIALIZATION IN VIOLENCE,CRIMINOLOGY, Issue 2 2007D. WAYNE OSGOOD Specialization in violence is an important scientific and policy topic, and over the past several decades, many analysis techniques for studying specialization have emerged. Research in this area continues to be hampered, however, by remaining methodological problems. To overcome these problems, we propose a new method for studying specialization in violence based on an item-response theory measurement approach that is implemented through a multilevel regression model. Our approach defines specialization as an individual level latent variable, takes into account the inherent confounds between specialization and overall level of offending, and gauges specialization relative to the population base rates of each offense. Our method also enables researchers to 1) estimate the extent and statistical significance of specialization, 2) assess the stability of specialization over time, and 3) relate specialization to explanatory variables. Using data from three studies, we found substantial levels of specialization in violence, considerable stability in specialization over time, and several significant and relatively consistent relationships of specialization to explanatory variables such as gender, parental education, and risk-seeking. [source] Analysis of force generation during flagellar assembly through optical trapping of free-swimming Chlamydomonas reinhardtiiCYTOSKELETON, Issue 3 2005Rachel Patton McCord Abstract Many studies have used velocity measurements, waveform analyses, and theoretical flagella models to investigate the establishment, maintenance, and function of flagella of the biflagellate green algae Chlamydomonas reinhardtii. We report the first direct measurement of Chlamydomonas flagellar swimming force. Using an optical trap ("optical tweezers") we detect a 75% decrease in swimming force between wild type (CC124) cells and mutants lacking outer flagellar dynein arms (oda1). This difference is consistent with previous estimates and validates the force measurement approach. To examine mechanisms underlying flagella organization and function, we deflagellated cells and examined force generation during flagellar regeneration. As expected, fully regenerated flagella are functionally equivalent to flagella of untreated wild type cells. However, analysis of swimming force vs. flagella length and the increase in force over regeneration time reveals intriguing patterns where increases in force do not always correspond with increases in length. These investigations of flagellar force, therefore, contribute to the understanding of Chlamydomonas motility, describe phenomena surrounding flagella regeneration, and demonstrate the advantages of the optical trapping technique in studies of cell motility. Cell Motil. Cytoskeleton 61:137,144, 2005. © 2005 Wiley-Liss, Inc. [source] Social functioning as an outcome measure in schizophrenia studiesACTA PSYCHIATRICA SCANDINAVICA, Issue 6 2007T. Burns Objective:, Deficits in social functioning are a core feature of schizophrenia. Method:, A literature search of English language articles published between January 1990 and December 2006 was undertaken to identify: i) scales used most frequently to assess social functioning in schizophrenia; and ii) the most frequently used social functioning scales in randomized, controlled trials of antipsychotics. A further search (without time limits) examined their psychometric properties. Results:, A total of 301 articles employed social functioning scales in the assessment of schizophrenia. These contained 87 potentially relevant measures. Only 14 randomized, controlled studies of antipsychotic agents were identified that examined social functioning. Scales varied greatly in terms of measurement approach, number and types of domains covered and scoring systems. A striking lack of data on psychometric properties was observed. Conclusion:, Limited consensus on the definition and measurement of social functioning exists. The Personal and Social Performance Scale is proposed as a useful tool in future research. [source] A Surface-Based Approach to Measuring Spatial SegregationGEOGRAPHICAL ANALYSIS, Issue 2 2007David O'Sullivan Quantitative indices of residential segregation have been with us for half a century, but suffer significant limitations. While useful for comparison among regions, summary indices fail to reveal spatial aspects of segregation. Such measures generally consider only the population mix within zones, not between them. Zone boundaries are treated as impenetrable barriers to interaction between population subgroups, so that measurement of segregation is constrained by the zoning system, which bears no necessary relation to interaction among population subgroups. A segregation measurement approach less constrained by the chosen zoning system, which enables visualization of segregation levels at the local scale and accounts for the spatial dimension of segregation, is required. We propose a kernel density estimation approach to model spatial aspects of segregation. This provides an explicitly geographical framework for modeling and visualizing local spatial segregation. The density estimation approach lends itself to development of an index of spatial segregation with the advantage of functional compatibility with the most widely used index of segregation (the dissimilarity index D). We provide a short review of the literature on measuring segregation, briefly describe the kernel density estimation method, and illustrate how the method can be used for measuring segregation. Examples using a simulated landscape and two empirical cases in Washington, DC and Philadelphia, PA are presented. [source] Health-related quality of life improves in children and adolescents with inflammatory bowel disease after attending a camp sponsored by the Crohn's and colitis foundation of AmericaINFLAMMATORY BOWEL DISEASES, Issue 2 2005Melissa A. Shepanski MS Abstract Purpose: To describe the reported health-related quality of life (HRQOL) in children and adolescents with inflammatory bowel disease (IBD) after attending an IBD summer camp. Methods: A prospective analysis of quality of life was completed at an overnight camp that was exclusively for patients with IBD, which was sponsored by the Crohn's and Colitis Foundation of America. The IMPACT-II questionnaire (Canada and United States) and the State-Trait Anxiety Inventory for Children were administered to the campers at the beginning and at the end of a 1-week camp to assess HRQOL and anxiety. The IMPACT-II questionnaire consists of 35 questions measuring 6 quality-of-life domains (i.e., bowel domain, systemic symptoms, emotional functioning, social functioning, body image, and treatment/interventions). The State-Trait Anxiety Inventory for Children consists of 2 different 20-item sets of questions. One set assesses state anxiety, and the other, trait anxiety. A repeated-measures multivariate analysis of variance was performed to determine the differences between scores attained before and after camp on the IMPACT-II questionnaire and in each of its domains. Paired sample t tests were performed on state and trait anxiety before and after camp. Results: A total of 125 individuals consented to participate, but 61 patients (50 girls and 11 boys; age range, 9 to 16 y) completed the IMPACT-II questionnaire in full. Of those 61 patients, 47 had Crohn's disease and 14 had ulcerative colitis. There was statistically significant improvement between the mean (±SD) precamp total score (172.95 ± 36.61) and the mean postcamp total score (178.71 ± 40.97; P = 0.035), bowel symptoms scores (P = 0.036), social functioning scores (P = 0.022), and treatment interventions scores (P = 0.012). No difference was found between anxiety scores before and after camp on either the state or trait anxiety inventories (n = 55; P > 0.05). Conclusions: Overall, HRQOL improved in children after attending IBD summer camp. This exploratory study suggests that contributing factors for these improvements may be an increase in social functioning, a better acceptance of IBD symptoms, and less distress regarding treatment interventions, suggesting that a camp that is specifically designed for children with IBD may normalize the chronic illness experience. However, future research using a multimodal measurement approach is warranted to support these conclusions. [source] Analysis of Participating Life Insurance Contracts: A Unification ApproachJOURNAL OF RISK AND INSURANCE, Issue 3 2007Nadine Gatzert Fair pricing of embedded options in life insurance contracts is usually conducted by using risk-neutral valuation. This pricing framework assumes a perfect hedging strategy, which insurance companies can hardly pursue in practice. In this article, we extend the risk-neutral valuation concept with a risk measurement approach. We accomplish this by first calibrating contract parameters that lead to the same market value using risk-neutral valuation. We then measure the resulting risk assuming that insurers do not follow perfect hedging strategies. As the relevant risk measure, we use lower partial moments, comparing shortfall probability, expected shortfall, and downside variance. We show that even when contracts have the same market value, the insurance company's risk can vary widely, a finding that allows us to identify key risk drivers for participating life insurance contracts. [source] Modelling Operational Losses: A Bayesian ApproachQUALITY AND RELIABILITY ENGINEERING INTERNATIONAL, Issue 5 2004Paolo Giudici Abstract The exposure of banks to operational risk has increased in recent years. The Basel Committee on Banking Supervision (known as Basel II) has established a capital charge to cover operational risks other than credit and market risk. According to the advanced methods defined in ,The New Basel Capital Accord' to quantify the capital charge, in this paper we present an advanced measurement approach based on a Bayesian network model that estimates an internal measure of risk of the bank. One of the main problems faced when measuring the operational risk is the scarcity of loss data. The methodology proposed solves this critical point because it allows a coherent integration, via Bayes' theorem, of different sources of information, such as internal and external data, and the opinions of ,experts' (process owners) about the frequency and the severity of each loss event. Furthermore, the model corrects the losses distribution by considering the eventual relations between different nodes of the network that represent the losses of each combination of business line/event type/bank/process and the effectiveness of the corresponding internal and external controls. The operational risk capital charge is quantified by multiplying the value at risk (VaR) per event, a percentile of the losses distribution determined, by an estimate of the number of losses that may occur in a given period. Furthermore, it becomes possible to monitor the effectiveness of the internal and external system controls in place at the bank. The methodology we present has been experimented as a pilot project in one of the most important Italian banking groups, Monte dei Paschi di Siena. Copyright © 2004 John Wiley & Sons, Ltd. [source] Single run measurements of drug-protein binding by high-performance frontal analysis capillary electrophoresis and mass spectrometryRAPID COMMUNICATIONS IN MASS SPECTROMETRY, Issue 12 2005Hong Wan A novel drug-protein binding measurement method based on high-performance frontal analysis and capillary electrophoresis (HPFA/CE) is presented. A single run measurement approach is proposed to circumvent utilization of a calibration curve that is often performed with HPFA. A sensitive mass spectrometer is applied as a detector enabling the measurement of in vitro protein binding at lower drug concentrations. Unbound free fraction and binding constants can be determined by a single run measurement by consecutive injections of an internal drug standard, a buffer plug and a drug-protein mixture. Effects of injection volumes on peak height and plateau profile were investigated in two different separation systems, non-volatile buffer and volatile buffer, with UV and mass spectrometry detection, respectively. A simplified one-to-one binding model is employed to evaluate the proposed method by using both single and multiple drug concentrations to measure the unbound free fraction and calculate the binding constants of some selected compounds. The method is suitable for rapid and direct screening of the binding of a drug to a specific protein or drug-plasma protein binding. Copyright © 2005 John Wiley & Sons, Ltd. [source] The Addiction Severity Index at 25: Origins, Contributions and TransitionsTHE AMERICAN JOURNAL ON ADDICTIONS, Issue 2 2006A. Thomas McLellan PhD The Addiction Severity Index (ASI) is a multidimensional interview used to measure the substance use, health, and social problems of those with alcohol and other drug problems, both at admission to treatment and subsequently at follow-up contacts. This article first discusses the conceptual and practical importance of the ASI's multi-dimensional approach to measuring addiction severity, as illustrated by two case presentations. The second section of the paper reviews how this measurement approach has led to some important findings regarding the prediction and measurement of addiction treatment effectiveness. The third section describes the historical and practical considerations that have changed the instrument over time, details the problems with the instrument, and describes our efforts to correct those problems with the ASI-6. Finally, some recent ASI data collected from over 8,400 patients admitted to a nationally representative sample of U.S. addiction treatment programs are presented. [source] A view from the bridge: agreement between the SF-6D utility algorithm and the Health Utilities IndexHEALTH ECONOMICS, Issue 11 2003Bernie J. O'Brien Abstract Background: The SF-6D is a new health state classification and utility scoring system based on 6 dimensions (,6D') of the Short Form 36, and permits a "bridging" transformation between SF-36 responses and utilities. The Health Utilities Index, mark 3 (HUI3) is a valid and reliable multi-attribute health utility scale that is widely used. We assessed within-subject agreement between SF-6D utilities and those from HUI3. Methods: Patients at increased risk of sudden cardiac death and participating in a randomized trial of implantable defibrillator therapy completed both instruments at baseline. Score distributions were inspected by scatterplot and histogram and mean score differences compared by paired t -test. Pearson correlation was computed between instrument scores and also between dimension scores within instruments. Between-instrument agreement was by intra-class correlation coefficient (ICC). Results: SF-6D and HUI3 forms were available from 246 patients. Mean scores for HUI3 and SF-6D were 0.61 (95% CI 0.60,0.63) and 0.58 (95% CI 0.54,0.62) respectively; a difference of 0.03 (p<0.03). Score intervals for HUI3 and SF-6D were (-0.21 to 1.0) and (0.30,0.95). Correlation between the instrument scores was 0.58 (95% CI 0.48,0.68) and agreement by ICC was 0.42 (95% CI 0.31,0.52). Correlations between dimensions of SF-6D were higher than for HUI3. Conclusions: Our study casts doubt on the whether utilities and QALYs estimated via SF-6D are comparable with those from HUI3. Utility differences may be due to differences in underlying concepts of health being measured, or different measurement approaches, or both. No gold standard exists for utility measurement and the SF-6D is a valuable addition that permits SF-36 data to be transformed into utilities to estimate QALYs. The challenge is developing a better understanding as to why these classification-based utility instruments differ so markedly in their distributions and point estimates of derived utilities. Copyright © 2003 John Wiley & Sons, Ltd. [source] Evaluation of Bioaccumulation Using In Vivo Laboratory and Field Studies,INTEGRATED ENVIRONMENTAL ASSESSMENT AND MANAGEMENT, Issue 4 2009Annie V Weisbrod Abstract A primary consideration in the evaluation of chemicals is the potential for substances to be absorbed and retained in an organism's tissues (i.e., bioaccumulated) at concentrations sufficient to pose health concerns. Substances that exhibit properties that enable biomagnification in the food chain (i.e., amplification of tissue concentrations at successive trophic levels) are of particular concern due to the elevated long-term exposures these substances pose to higher trophic organisms, including humans. Historically, biomarkers of in vivo chemical exposure (e.g., eggshell thinning, bill deformities) retrospectively led to the identification of such compounds, which were later categorized as persistent organic pollutants. Today, multiple bioaccumulation metrics are available to quantitatively assess the bioaccumulation potential of new and existing chemicals and identify substances that, upon or before environmental release, may be characterized as persistent organic pollutants. This paper reviews the various in vivo measurement approaches that can be used to assess the bioaccumulation of chemicals in aquatic or terrestrial species using laboratory-exposed, field-deployed, or collected organisms. Important issues associated with laboratory measurements of bioaccumulation include appropriate test species selection, test chemical dosing methods, exposure duration, and chemical and statistical analyses. Measuring bioaccumulation at a particular field site requires consideration of which test species to use and whether to examine natural populations or to use field-deployed populations. Both laboratory and field methods also require reliable determination of chemical concentrations in exposure media of interest (i.e., water, sediment, food or prey, etc.), accumulated body residues, or both. The advantages and disadvantages of various laboratory and field bioaccumulation metrics for assessing biomagnification potential in aquatic or terrestrial food chains are discussed. Guidance is provided on how to consider the uncertainty in these metrics and develop a weight-of-evidence evaluation that supports technically sound and consistent persistent organic pollutant and persistent, bioaccumulative, and toxic chemical identification. Based on the bioaccumulation information shared in 8 draft risk profiles submitted for review under the United Nations Stockholm Convention, recommendations are given for the information that is most critical to aid transparency and consistency in decision making. [source] Approaches for Quantifying the Metabolism of Physical Economies: A Comparative Survey: Part II: Review of Individual ApproachesJOURNAL OF INDUSTRIAL ECOLOGY, Issue 1 2002Peter L. Daniels Summary This article is the second of a two-part series that describes and compares the essential features of nine "physical economy" approaches for mapping and quantifying the material demands of the human economy upon the natural environ-ment. These approaches are critical tools in the design and implementation of industrial ecology strategies for greater eco-efficiency and reduced environmental impacts of human economic activity. Part I of the series provided an overview, meth-odological classification, and comparison of a selected set of major materials flow analysis (MFA) and related techniques. This sequel includes a convenient reference and overview of the major metabolism measurement approaches in the form of a more detailed summary of the key specific analytical and other features of the approaches introduced in part I. The surveyed physical economy related environmental analysis ap-proaches include total material requirement and output mod-els, bulk MFA (IFF (Department of Social Ecology, Institute for Interdiscplinary Studies of Austrian Universities) material flow balance model variant), physical input-output tables, substance flow analysis, ecological footprint analysis, environmental space, material intensity per unit service, life-cycle assessment (LCA), the sustainable process index, and company-level MFA. [source] Childhood Maltreatment and Antisocial Behavior: Comparison of Self-Reported and Substantiated MaltreatmentAMERICAN JOURNAL OF ORTHOPSYCHIATRY, Issue 2 2008Carolyn A. Smith PhD Although accurate assessment of maltreatment is critical to understanding and interrupting its impact on the life course, comparison of different measurement approaches is rare. The goal of this study is to compare maltreatment reports from official Child Protective Services (CPS) records with retrospectively self-reported measures. Research questions address the prevalence and concordance of each type of measure, their relationship to social disadvantage, and their prediction to four antisocial outcomes in adolescence and early adulthood including arrest, self-reported violence, general offending, and illegal drug use. Data to address this comparison come from the Rochester Youth Development Study (RYDS), a longitudinal panel study of 1,000 adolescents. Findings indicate that self-reported retrospective maltreatment is somewhat more prevalent (29%) than official substantiated maltreatment (21%). Among those with official reports, in young adulthood about half self-reported maltreatment, whereas 37% of those self-reporting have an official report. In general, both sources suggest that maltreatment is associated with a higher prevalence of antisocial behavior. It is not clear that combining sources of information improves prediction. [source] Study of the near-neutral pH-sensitivity of chitosan/gelatin hydrogels by turbidimetry and microcantilever deflectionBIOTECHNOLOGY & BIOENGINEERING, Issue 3 2006Jinshu Mao Abstract The fundamental properties and pH-sensitivity of chitosan/gelating hydrogels were investigated using spectroscopic and microelectro mechanical (MEMS) measurement approaches. Turbidimetric titration revealed that there were electrostatic attractive interactions between tripolyphosphate (TPP), chitosan, and gelatin in the acidic pH range, depending on their degree of ionization. The pH-sensitive swelling behavior of the hydrogels was investigated by monitoring the deflection of hydrogel-coated microcantilevers, which exhibited a sensitive and repeatable response to solution pH. The deflection of the microcantilever increased as the pH decreased, and the response speed of the system exhibited a nearly linear relationship with pH. The effects of the pH and concentration of TPP solution, as well as the ratio of chitosan to gelatin in gel precursor solutions, on the pH sensitivity of the hydrogels were also investigated. It was found that the swelling of the hydrogel is mainly a result of chain relaxation of chitosan,TPP complexes caused by protonation of free amino groups in chitosan, which depends on the crosslinking density set during the formation of the network. An increase in initial crosslink density induced a decrease in swelling and pH sensitivity. It can be concluded from this study that pH-sensitive chitosan gel properties can be tuned by preparatory conditions and inclusion of gelatin. Furthermore, microcantilevers can be used as a platform for gaining increased understanding of environmentally sensitive polymers. © 2006 Wiley Periodicals, Inc. [source] | |||||||||||||||||||