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241.
Wavelet thresholding of spectra has to be handled with care when the spectra are the predictors of a regression problem. Indeed, a blind thresholding of the signal followed by a regression method often leads to deteriorated predictions. The scope of this article is to show that sparse regression methods, applied in the wavelet domain, perform an automatic thresholding: the most relevant wavelet coefficients are selected to optimize the prediction of a given target of interest. This approach can be seen as a joint thresholding designed for a predictive purpose. The method is illustrated on a real world problem where metabolomic data are linked to poison ingestion. This example proves the usefulness of wavelet expansion and the good behavior of sparse and regularized methods. A comparison study is performed between the two-steps approach (wavelet thresholding and regression) and the one-step approach (selection of wavelet coefficients with a sparse regression). The comparison includes two types of wavelet bases, various thresholding methods, and various regression methods and is evaluated by calculating prediction performances. Information about the location of the most important features on the spectra was also obtained and used to identify the most relevant metabolites involved in the mice poisoning.  相似文献   
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243.
In this article, we propose a new multiple test procedure for assessing multivariate normality, which combines BHEP (Baringhaus–Henze–Epps–Pulley) tests by considering extreme and nonextreme choices of the tuning parameter in the definition of the BHEP test statistic. Monte Carlo power comparisons indicate that the new test presents a reasonable power against a wide range of alternative distributions, showing itself to be competitive against the most recommended procedures for testing a multivariate hypothesis of normality. We further illustrate the use of the new test for the Fisher Iris dataset.  相似文献   
244.
A ship that is not under control (NUC) is a typical incident that poses serious problems when in confined waters close to shore. The emergency response to NUC ships is to select the best risk control options, which is a challenge in restricted conditions (e.g., time limitation, resource constraint, and information asymmetry), particularly in inland waterway transportation. To enable a quick and effective response, this article develops a three‐stage decision‐making framework for NUC ship handling. The core of this method is (1) to propose feasible options for each involved entity (e.g., maritime safety administration, NUC ship, and ships passing by) under resource constraint in the first stage, (2) to select the most feasible options by comparing the similarity of the new case and existing cases in the second stage, and (3) to make decisions considering the cooperation between the involved organizations by using a developed Bayesian network in the third stage. Consequently, this work provides a useful tool to achieve well‐organized management of NUC ships.  相似文献   
245.
This paper provides a contemporary and comprehensive review of work in the marketing channel field that is based on French and Raven's power‐base theory. It traces the development of theoretic, conceptual and methodological orthodoxies from the 1970s. Mirroring the movement towards the relationship marketing paradigm, the paper considers the theory's empirical contribution to knowledge of power, conflict, trust and commitment in marketing channels. Limitations relating to inconsistency of treatment, contradictory findings and the simplification of complex phenomena are identified. Nevertheless, current work extends power‐base theory to other cultures, other styles of research and to the area of supply chains. The review raises questions about the value of contribution made using this theory and notes the surprising absence within the channels literature of the broader, current debate about power. To illustrate, the paper shows how Clegg's (1989. Frameworks of Power. London: Sage) circuits of power framework, if applied to channel contexts, could address forms of power that are invisible, anonymous and not necessarily negative. Applications and methods are discussed, opening a space wherein a broadened understanding of power is integrated within a focus upon cooperative channels.  相似文献   
246.
In a smoothing spline model with unknown change-points, the choice of the smoothing parameter strongly influences the estimation of the change-point locations and the function at the change-points. In a tumor biology example, where change-points in blood flow in response to treatment were of interest, choosing the smoothing parameter based on minimizing generalized cross-validation (GCV) gave unsatisfactory estimates of the change-points. We propose a new method, aGCV, that re-weights the residual sum of squares and generalized degrees of freedom terms from GCV. The weight is chosen to maximize the decrease in the generalized degrees of freedom as a function of the weight value, while simultaneously minimizing aGCV as a function of the smoothing parameter and the change-points. Compared with GCV, simulation studies suggest that the aGCV method yields improved estimates of the change-point and the value of the function at the change-point.  相似文献   
247.
As one of a suite of natural science galleries in the National Museum of Scotland, Animal Senses presents a comprehensive overview of how animals have evolved senses as they have adapted to different ecological niches in order to find food or avoid predation. Using different sensory channels, they also have evolved means of communication to attract mates, deter rivals, and remain hidden from predators and prey. Some of the most extraordinary examples of evolution are those which mimic the appearance of another unrelated species or some feature of the environment such as a thorn on a bush or a piece of coral. New taxidermy and models, engaging text presented hierarchically, and fun interactives were developed specifically for this gallery in order to present an up-to-date review of senses and communication. However, its real strength is the wide array of real specimens and life-size models which allow visitors to see what these animals really look like and how big they are, experiences which cannot be emulated by books or electronic media. By taking a thematic approach, we have created an unrivalled opportunity to compare animals from different taxonomic groups to see how they have solved the problems of life by evolving similar structures or completely different ones in order to find food, avoid being eaten, navigate, find mates and deceive rivals and predators.  相似文献   
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249.
Despite increasing research into how the structural characteristics of slot machines influence gambling behaviour there have been no experimental investigations into the effect of free-spins bonus features—a structural characteristic that is commonly central to the design of slot machines. This series of three experiments investigated the free-spins feature using slot machine simulations to determine whether participants allocate more wagers to a machine with free spins, and, which components of free-spins features drive this preference. In each experiment, participants were exposed to two computer-simulated slot machines—one with a free-spins feature or similar bonus feature and one without. Participants then completed a testing phase where they could freely switch between the two machines. In Experiment 1, participants did not prefer the machine with a simple free-spins feature. In Experiment 2 the free-spins feature incorporated additional elements such as sounds, animations, and an increased win frequency; participants preferred to gamble on this machine. The Experiment 3 “bonus feature” machine resembled the free spins machine in Experiment 2 except spins were not free; participants showed a clear preference for this machine also. These findings indicate that (1) free-spins features have a major influence over machine choice and (2) the “freeness” of the free-spins bonus features is not an important driver of preference, contrary to self-report and interview research with gamblers.  相似文献   
250.
The aim of this article is to analyze the difficulties in professionalizing the long-term care system in Spain. Since 2006, the new Spanish law has recognized care as a subjective right, and regulations are being designed to create a framework for its professionalization. Nowadays, family remains the most important group of providers who care for their elders, and women remain the main informal caregivers. Why do families resist using public long-term care services and professional carers included in the new law? The hypothesis highlights sociocultural factors as an obstacle to professionalization of long-term care services in addition to political and economic factors. The results show qualitative data about expectations, preferences, and discourses that women caregivers have in relation to their responsibility. The empirical material includes 25 interviews with different profiles of caregivers and six focus groups with family caregivers. The article suggests that the Spanish ideal of care is a problem for the professionalization of services because the family remains as the main provider of care—without specific skills, knowledge, and abilities.  相似文献   
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