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Empirical Validation (empirical + validation)
Selected AbstractsValidation of Tool Mark Comparisons Obtained Using a Quantitative, Comparative, Statistical AlgorithmJOURNAL OF FORENSIC SCIENCES, Issue 4 2010L. Scott Chumbley Ph.D. Abstract:, A statistical analysis and computational algorithm for comparing pairs of tool marks via profilometry data is described. Empirical validation of the method is established through experiments based on tool marks made at selected fixed angles from 50 sequentially manufactured screwdriver tips. Results obtained from three different comparison scenarios are presented and are in agreement with experiential knowledge possessed by practicing examiners. Further comparisons between scores produced by the algorithm and visual assessments of the same tool mark pairs by professional tool mark examiners in a blind study in general show good agreement between the algorithm and human experts. In specific instances where the algorithm had difficulty in assessing a particular comparison pair, results obtained during the collaborative study with professional examiners suggest ways in which algorithm performance may be improved. It is concluded that the addition of contextual information when inputting data into the algorithm should result in better performance. [source] Optimum futures hedge in the presence of clustered supply and demand shocks, stochastic basis, and firm's costs of hedgingTHE JOURNAL OF FUTURES MARKETS, Issue 12 2003Carolyn W. Chang In a doubly stochastic jump-diffusion economy with stochastic jump arrival intensity and proportional transaction costs, we develop a five-factor risk-return asset pricing inequality to model optimum futures hedge in the presence of clustered supply and demand shocks, stochastic basis, and firm's costs of hedging. Concave risk-return tradeoff dictates a hedge ratio to be substantially less than the traditional risk-minimization one. The ratio now comprises a positive diffusion, a positive jump, and a negative hedging cost component. The faster jumps arrive, and the more hedging costs, the more pronounced are the respective jump and hedging cost effects. Empirical validation confirms that actual industry hedge ratios vary significantly across firm's costs of and efficiency in hedging and are significantly lower than what risk-minimization dictates. The model also can be used to compute a threshold production level for determining if a firm should hedge. © 2003 Wiley Periodicals, Inc. Jrl Fut Mark 23:1209,1237, 2003 [source] The Italian experience in social reporting: an empirical analysisCORPORATE SOCIAL RESPONSIBILITY AND ENVIRONMENTAL MANAGEMENT, Issue 3 2006Davide Secchi Abstract This analysis tries to discover an empirical validation to back up the hypothesis that the Italian phenomenon of social reporting has changed with regard to the past and is growing in importance. After considering the evolution of Italian literature on the issue, the paper tries to find connections between this literature and social reporting practices. Empirical findings are based on 62 Italian social reports. The paper tries to answer three questions: (a) what kind of organization publishes social reports; (b) what are the main differences, if any, between different reports belonging to diverse organizations; (c) which are the leading models. Social reports have been sorted according to three main issues: report objectives, emerging models and stakeholder mapping. Collected data suggest that there is a common ground for organizations in socially responsible behaviour, but also that this common ground fits the need of every single organization. Copyright © 2005 John Wiley & Sons, Ltd and ERP Environment. [source] Language phenotypes and intervention planning: Bridging research and practiceDEVELOPMENTAL DISABILITIES RESEARCH REVIEW, Issue 1 2007Deborah J. Fidler Abstract This paper focuses on the communication and language phenotypes associated with three genetic disorders: Down syndrome, Williams syndrome, and fragile X syndrome. It is argued that there is empirical evidence that these disorders predispose children to specific profiles of strength and weakness in some areas of speech, language, and communication, and that intervention planning for children with each syndrome may take an approach informed by these profiles. Issues related to within-group variability, shared outcomes among syndromes, and the need for empirical validation for syndrome-specific recommendations are discussed. © 2007 Wiley-Liss, Inc. MRDD Research Reviews 2007; 13:47,57. [source] Validating the Relationship Qualities of Influence and Persuasion With the Family Social Relations ModelHUMAN COMMUNICATION RESEARCH, Issue 1 2003Rachel Oakley Hsiung Influence and persuasion are related, fundamental constructs in interpersonal communication. Both display the relationship qualities of interdependence, bidirectionality, reciprocity, and multiple levels of analysis. Yet, empirical validation of these relationship qualities is lacking, largely due to an absence of appropriate methods and statistical procedures. This article uses the family social relations model (SRM) to test for the personal relationship qualities of influence and persuasion in the family decision-making context of buying a new car. New relationship measures of influence and persuasion were developed because, historically, measures have been at the individual level. The sample size of 110 families proved sufficient for stable parameter estimates. The results uncovered patterns in the relationship qualities of influence and persuasion across 3 decisions families make when buying a new car (i.e., how much to spend, car model choice, final decision). The findings confirm that both influence and persuasion are truly relational. The novel use of the model across decisions allowed the patterns of relationships among family members to be compared, and demonstrated the importance of the relationship qualities of influence and persuasion in decision making. Predictions were examined across decisions as well so as to check the consistency of hypotheses. The results provide further insight into the meaning of influence and persuasion, and of SRM terms. [source] Knowledge-sharing reward dynamics in knowledge management systems: Game theory,based empirical validationHUMAN FACTORS AND ERGONOMICS IN MANUFACTURING & SERVICE INDUSTRIES, Issue 2 2010Xi Zhang Abstract There are several knowledge-sharing problems in knowledge-management system (KMS) contexts. Many organizations use rewards to motivate people to contribute knowledge, but there has been no conclusive evidence of the role of reward. We designed two game-theory models to explain why and how the different knowledge-sharing problems occur in a KMS and the effectiveness of rewards. We found that there are four types of Nash equilibriums in different knowledge-sharing situations (Perfect, Free-riding, Non-use, and Dormant). Complex situations also occur (e.g., the absence of consideration for knowledge quality leads to vicious cycles). People contribute low-quality knowledge that is not used, and thus the KMS spirals toward disuse. To provide proposition evidence, a case study in an enterprise resource planning vendor was conducted. Based on comparison with empirical evidence, proposition validity was ensured. To effectively facilitate knowledge sharing, our suggestion is that organizations not only add rewards but also apply some additional mechanisms, such as a quality-evaluating system, extended information technology support, and organizational policy. © 2010 Wiley Periodicals, Inc. [source] Fuzzy quantification in two real scenarios: Information retrieval and mobile roboticsINTERNATIONAL JOURNAL OF INTELLIGENT SYSTEMS, Issue 6 2009Félix Díaz-Hermida Fuzzy quantification supplies powerful tools for handling linguistic expressions. Nevertheless, its advantages are usually shown at the theoretical level without a proper empirical validation. In this work, we review the application of fuzzy quantification in two application domains. We provide empirical evidence on the adequacy of fuzzy quantification to support different tasks in the context of mobile robotics and information retrieval. This practical perspective aims at exemplifying the actual benefits that real application can get from fuzzy quantifiers. © 2009 Wiley Periodicals, Inc. [source] Reconceptualizing the learning transfer conceptual framework: empirical validation of a new systemic modelINTERNATIONAL JOURNAL OF TRAINING AND DEVELOPMENT, Issue 3 2004Constantine Kontoghiorghes The main purpose of this study was to examine the validity of a new systemic model of learning transfer and thus determine if a more holistic approach to training transfer could better explain the phenomenon. In all, this study confirmed the validity of the new systemic model and suggested that a high performance work system could indeed serve as a catalyst to successful training transfer. [source] Networking characteristics of African-American managers: empirical validation and training applicationsINTERNATIONAL JOURNAL OF TRAINING AND DEVELOPMENT, Issue 4 2000Stéphane Brutus This article describes the impact of informal networks on managerial effectiveness in general and, more specifically, for that of African-American managers. Previous research has demonstrated that network characteristics conducive to increased performance for African-Americans differed significantly from those of white managers (e.g. Ibarra, 1995). These results are further validated in this study through the use of a different performance measure. Networking characteristics and multi-raters' performance information were collected from 185 managers. Results show that high performing African-American managers possess informal networks composed of a higher proportion of other African-Americans than their low performing counterparts. The reverse trend was found for white managers. A description of a training module based on these results is offered. [source] The non-linear dynamics of output and unemployment in the U.S.JOURNAL OF APPLIED ECONOMETRICS, Issue 4 2001Filippo Altissimo This paper studies the joint dynamics of U.S. output and unemployment rate in a non-linear VAR model. The non-linearity is introduced through a feedback variable that endogenously augments the output lags of the VAR in recessionary phases. Sufficient conditions for the ergodicity of the model, potentially applying to a larger class of threshold models, are provided. The linear specification is rejected in favour of our threshold VAR. However, in the estimation the feedback is found to be statistically significant only on unemployment, while it transmits to output through its cross-correlation. This feedback effect from recessions generates important asymmetries in the propagation of shocks, a possible key to interpret the divergence in the measures of persistence in the literature. The regime-dependent persistence also explains the finding that the feedback from recession exerts a positive effect on the long-run growth rate of the economy, an empirical validation of the Schumpeterian macroeconomic theories. Copyright © 2001 John Wiley & Sons, Ltd. [source] The Organizational Life of an Idea: Integrating Social Network, Creativity and Decision-Making Perspectives*JOURNAL OF MANAGEMENT STUDIES, Issue 6 2007Bob Kijkuit abstract Existing theories on the influence of social networks on creativity focus on idea generation. Conversely, the new product development literature concentrates more on the selection of ideas and projects. In this paper we bridge this gap by developing a dynamic framework for the role of social networks from idea generation to selection. We apply findings from creativity and behavioural decision-making literature and present an in-depth understanding of the sociological processes in the front-end of the new product development process. Our framework builds on the importance of mutual understanding, sensemaking and consensus formation. The propositions focus on both network structure and content and highlight the need to have strong ties and prior related knowledge, to incorporate decision makers, and to move over time from a large, non-redundant and heterogeneous to a smaller and more cohesive network structure. We conclude with a discussion on empirical validation of the framework and possible extensions. [source] Measuring the complexity of class diagrams in reverse engineeringJOURNAL OF SOFTWARE MAINTENANCE AND EVOLUTION: RESEARCH AND PRACTICE, Issue 5 2006Frederick T. Sheldon Abstract Complexity metrics for object-oriented systems are plentiful. Numerous studies have been undertaken to establish valid and meaningful measures of maintainability as they relate to the static structural characteristics of software. In general, these studies have lacked the empirical validation of their meaning and/or have only succeeded in evaluating partial aspects of the system. In this study we have determined, through limited empirical means, a practical and holistic view by analyzing and comparing the structural characteristics of UML class diagrams as those characteristics relate to or impact maintainability. Class diagrams are composed of three kinds of relation, association, generalization, and aggregation, which make their overall structure difficult to understand. We propose combining these three relations in such a way that enables a comprehensive measure of complexity. Theoretically, this measure is applicable among different class diagrams (including different domains, platforms or systems) to the extent that the measure is widely comparative and context free. Further, this property does not preclude comparison within a specific class diagram (or family) and is therefore very useful in evaluating a given class diagram's strengths and weaknesses. We are reporting empirical results that provide a small measure of validity to enable an objective appraisal of both complexity and maintainability without equating the two. Therefore, to evaluate our structural complexity metric, we determined the level of understandability of the system by measuring the time needed to reverse engineer source code into class diagrams including the number of errors produced while creating the diagram. The number of errors produced offers one indicator of maintainability. The results, as compared with other complexity metrics, indicate that our metric shows promise especially if proven to be scalable. Copyright © 2006 John Wiley & Sons, Ltd. [source] A Native-Like Ability to CircumlocuteMODERN LANGUAGE JOURNAL, Issue 2 2000Sarah Jourdain The ability to circumlocute successfully is of utmost importance in compensating for gaps in lexical knowledge. Although all studies indicate that one's ability to circumlocute increases with increasing proficiency, it is interesting that little attention has been paid to those learners who have the greatest ability to circumlocute, native-like speakers. This study addresses the norms of native and native-like circumlocution. It expands the discussion of strategies involved in this skill to include the means by which speakers frame their message and thereby set the linguistic context for their listeners. Participants in this study, both native and native-like speakers, were found to employ similar strategies while circumlocuting, including the use of synonyms, analogies, and descriptions. These participants also consistently framed their speech to facilitate listener comprehension, and they frequently included in their discourse some reference to their status as a nonexpert in the field. Similarities in native and native-like circumlocution found in this study help to provide some empirical validation to the notion of "native-like." [source] Conceptual Models of Health Behavior: Research in the Emergency Care SettingsACADEMIC EMERGENCY MEDICINE, Issue 11 2009Edwin D. Boudreaux PhD Abstract This article provides recommendations for incorporating conceptual models of health behavior change into research conducted in emergency care settings. The authors drafted a set of preliminary recommendations, which were reviewed and discussed by a panel of experienced investigators attending the 2009 Academic Emergency Medicine consensus conference. The original recommendations were expanded and refined based on their input. This article reports the final recommendations. Three recommendations were made: 1) research conducted in emergency care settings that focuses on health behaviors should be grounded in formal conceptual models, 2) investigators should clearly operationalize their outcomes of interest, and 3) expected relations between theoretical constructs and outcomes should be made explicit prior to initiating a study. A priori hypothesis generation grounded in conceptual models of health behavior, followed by empirical validation of these hypotheses, is needed to improve preventive and public health,related interventions in emergency care settings. [source] Darwinian fitness, evolutionary entropy and directionality theoryBIOESSAYS, Issue 11 2005Klaus Dietz Two recent articles1,2 provide computational and empirical validation of the following analytical fact: the outcome of competition between an invading genotype and that of a resident population is determined by the rate at which the population returns to its original size after a random perturbation. This phenomenon can be quantitatively described in terms of the demographic parameter termed "evolutionary entropy", a measure of the variability in the age at which individuals produce offspring and die. The two articles also validate certain predictions of directionality theory, an evolutionary model that integrates demography and ecology with population genetics. In particular, directionality theory predicts that in populations that spend the greater part of their life cycle in the stationary growth phase, evolution will result in an increase in entropy. These species will be described by a late age of sexual maturity, small progeny sets and a broad reproductive time-span. In populations that undergo large fluctuations in size, however, the evolutionary outcome will be different. When the average size is large, evolution will result in a decrease in entropy,these populations will be described by early age of sexual maturity, large numbers of offspring and narrow reproductive span but when the average size is small, the evolutionary outcome will be random and non-directional. BioEssays 27:1097,1101, 2005. © 2005 Wiley Periodicals, Inc. [source] | ||||||||||||||||