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Rigorous Testing (rigorous + testing)
Selected AbstractsNear-Term Travel Speed Prediction Utilizing Hilbert,Huang TransformCOMPUTER-AIDED CIVIL AND INFRASTRUCTURE ENGINEERING, Issue 8 2009Khaled Hamad In this study, we propose an innovative methodology for such prediction. Because of the inherently direct derivation of travel time from speed data, the study was limited to the use of speed only as a single predictor. The proposed method is a hybrid one that combines the use of the empirical mode decomposition (EMD) and a multilayer feedforward neural network with backpropagation. The EMD is the key part of the Hilbert,Huang transform, which is a newly developed method at NASA for the analysis of nonstationary, nonlinear time series. The rationale for using the EMD is that because of the highly nonlinear and nonstationary nature of link speed series, by decomposing the time series into its basic components, more accurate forecasts would be obtained. We demonstrated the effectiveness of the proposed method by applying it to real-life loop detector data obtained from I-66 in Fairfax, Virginia. The prediction performance of the proposed method was found to be superior to previous forecasting techniques. Rigorous testing of the distribution of prediction errors revealed that the model produced unbiased predictions of speeds. The superiority of the proposed model was also verified during peak periods, midday, and night. In general, the method was accurate, computationally efficient, easy to implement in a field environment, and applicable to forecasting other traffic parameters. [source] A review of the epidemiological transition in dementia , cross-national comparisons of the indices related to Alzheimer's disease and vascular dementiaACTA PSYCHIATRICA SCANDINAVICA, Issue 1 2001Guk-Hee Suh Objective: To examine temporal changes in the prevalence of dementia and associated factors. Method: All publications on the epidemiology of dementia were identified using a medline search for the years 1966,1999. Results: Alzheimer's disease (AD) has become nearly twice as prevalent as vascular dementia (VaD) in Korea, Japan, and China since transition in early 1990s. Prior to this, in the 1980s, VaD was more prevalent than AD in these countries. In Nigeria, the prevalence of dementia was low. Indian studies were contradictory, with both AD and VaD being more prevalent in different studies. American and European studies consistently reported AD to be more prevalent than VaD. Conclusion: A theoretical model of transition from low incidence,high mortality society to high incidence,high mortality society to low incidence,low mortality society may explain these findings. Rigorous testing in prospective, longitudinal and population-based cross-national studies using culture-fair diagnostic instruments is required. [source] The role of banned substance residue analysis in the control of dietary supplement contaminationDRUG TESTING AND ANALYSIS, Issue 9 2010Dr Catherine MG Judkins Abstract The potential for contaminated dietary supplements to result in a failed doping test remains a concern for athletes, trainers, and sporting authorities despite improvements to regulatory guidelines. Previous surveys of readily available supplements confirm that many are contaminated with steroids and stimulants prohibited for use in elite sport. Suggested responses to this issue include the complete avoidance of all supplements. Many athletes, however, use nutritional supplements to achieve effective training and also to ensure that daily nutritional requirements are met (e.g. recommended levels of vitamins and minerals). This ensures that the use of supplements is and will remain the norm for a range of sports. As a result, an alternative approach of rigorous testing of materials destined for use by elite athletes has been introduced in several countries. While the testing of final product for banned substances may help mitigate the problem, it will not help to remove the underlying issue of contamination. In this article we describe an alternative approach that uses appropriate quality assurance procedures backed up by testing to remove sources of contamination. The decrease in the incidence of contamination amongst supplement companies adopting such a system is explained, and contrasted with the relatively high incidences of contamination found in products that are not part of a quality system. These findings are of key importance to both supplement manufacturers and those involved in advising athletes about supplement use. Copyright © 2010 John Wiley & Sons, Ltd. [source] Testing the use of interviews as a tool for monitoring trends in the harvesting of wild speciesJOURNAL OF APPLIED ECOLOGY, Issue 4 2008Julia P. G. Jones Summary 1Many aspects of human behaviour impact on ecological systems. Ecologists therefore need information on changes in these behaviours and are increasingly using methods more familiar to social scientists. 2Understanding patterns of wildlife harvesting is important for assessing the sustainability of harvests. Interviews are commonly used in which informants are asked to summarize their activities over a period of time. However, few studies have investigated the reliability of such data, the usefulness of interviews for monitoring trends, and how their information content can be maximized. 3We carried out rapid assessment interviews with villagers in Madagascar about the quantity, timing and spatial patterns of crayfish Astacoides granulimanus and firewood collection. We compared the results with information from daily interviews with the same informants. We used mixed models to investigate how accurately people reported their activities in the rapid assessment interviews, and estimated the probability of detecting a change in harvesting from two such interviews using a Bayesian approach. 4The interviews provided reliable information on quantities, effort, and the spatial pattern of harvesting. Simulations suggested the interviews would detect changes in catches and harvesting effort with reasonable power; for example, a 20% change in the amount of time spent crayfish harvesting could be detected with 90% power. Power is higher when the same informants are questioned in repeat interviews. 5Synthesis and applications. Ecologists are increasingly using social techniques and it is vital that they are subject to rigorous testing to ensure robustness in trend detection. This study suggests that interviews can be used to monitor changes in harvesting patterns by resource users, but whether the power is adequate will depend on the needs of the study. To maximize the power of interviews, informants should be interviewed independently and the same informants interviewed in subsequent years. [source] Performance assessment in health care providers: a critical review of evidence and current practiceJOURNAL OF NURSING MANAGEMENT, Issue 8 2007KAREN E. STC. Aim, To evaluate methods of performance assessment through an international literature review and a survey of current practice. Background, Over the past two decades health care organizations have focussed on promoting high quality care in conjunction with retaining motivated staff. Cognisant of such initiatives, we sought to evaluate assessment methods for qualified staff according to their utility in the working environment. Methods, A systematic literature search was completed and each paper independently reviewed. All health care organizations in Northern Ireland submitted details of their performance assessments. Each was critically appraised using a utility index. Results, Performance was not universally defined. A broad range of assessments were identified, each method had advantages and disadvantages. Although many lacked rigorous testing, areas of good practice were also noted. Conclusions, No single method is appropriate for assessing clinical performance. Rather, this study endorses proposals for a multi-method strategy to ensure that performance assessment demonstrates all attributes required for effective nursing and midwifery practice. [source] Popper and nursing theoryNURSING PHILOSOPHY, Issue 1 2003Peter Allmark P h D Abstract Science seems to develop by inducing new knowledge from observation. However, it is hard to find a rational justification for induction. Popper offers one attempt to resolve this problem. Nursing theorists have tended to ignore or reject Popper, often on the false belief that he is a logical positivist (and hence hostile to qualitative research). Logical positivism claims that meaningful sentences containing any empirical content should ultimately be reducible to simple, observation statements. Popper refutes positivism by showing that there are no such simple statements. He is not a positivist. For Popper, the scientist begins with problems and puts forward trial solutions. These are subjected to rigorous testing aimed at falsifying them. A new theoretical position is then reached in which the scientist knows either that the trial solutions are false or that they have not yet been falsified. Science is characterized by the fact that it tests its ideas through attempted falsification. Non-science tests its ideas through attempted refutation. Nursing theory is a mixture of science and non-science. Popper's method requires rigorous testing of theory in both realms. As such, some nursing theory should be discarded. Popper's view faces at least two important criticisms. One is that a scientist can always reject an apparent falsification by instead altering some auxiliary hypothesis (e.g. denying the accuracy of the falsifying observation). Popper can deal with this argument by saying that defence of a theory in this way will eventually break down if the theory is false. The second criticism is that Popper's method does ultimately draw upon induction. This criticism is true, but his method can be usefully adapted. An adapted from of Popper's philosophy of science provides a good basis for nursing theory. [source] Dopamine and Oxytocin Interactions Underlying Behaviors: Potential Contributions to Behavioral DisordersCNS: NEUROSCIENCE AND THERAPEUTICS, Issue 3 2010Tracey A. Baskerville Dopamine is an important neuromodulator that exerts widespread effects on the central nervous system (CNS) function. Disruption in dopaminergic neurotransmission can have profound effects on mood and behavior and as such is known to be implicated in various neuropsychiatric behavioral disorders including autism and depression. The subsequent effects on other neurocircuitries due to dysregulated dopamine function have yet to be fully explored. Due to the marked social deficits observed in psychiatric patients, the neuropeptide, oxytocin is emerging as one particular neural substrate that may be influenced by the altered dopamine levels subserving neuropathologic-related behavioral diseases. Oxytocin has a substantial role in social attachment, affiliation and sexual behavior. More recently, it has emerged that disturbances in peripheral and central oxytocin levels have been detected in some patients with dopamine-dependent disorders. Thus, oxytocin is proposed to be a key neural substrate that interacts with central dopamine systems. In addition to psychosocial improvement, oxytocin has recently been implicated in mediating mesolimbic dopamine pathways during drug addiction and withdrawal. This bi-directional role of dopamine has also been implicated during some components of sexual behavior. This review will discuss evidence for the existence dopamine/oxytocin positive interaction in social behavioral paradigms and associated disorders such as sexual dysfunction, autism, addiction, anorexia/bulimia, and depression. Preliminary findings suggest that whilst further rigorous testing has to be conducted to establish a dopamine/oxytocin link in human disorders, animal models seem to indicate the existence of broad and integrated brain circuits where dopamine and oxytocin interactions at least in part mediate socio-affiliative behaviors. A profound disruption to these pathways is likely to underpin associated behavioral disorders. Central oxytocin pathways may serve as a potential therapeutic target to improve mood and socio-affiliative behaviors in patients with profound social deficits and/or drug addiction. [source] | |||||||||||||