884 resultados para Emperical orthogonal functions


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During the last part of the 1990s the chance of surviving breast cancer increased. Changes in survival functions reflect a mixture of effects. Both, the introduction of adjuvant treatments and early screening with mammography played a role in the decline in mortality. Evaluating the contribution of these interventions using mathematical models requires survival functions before and after their introduction. Furthermore, required survival functions may be different by age groups and are related to disease stage at diagnosis. Sometimes detailed information is not available, as was the case for the region of Catalonia (Spain). Then one may derive the functions using information from other geographical areas. This work presents the methodology used to estimate age- and stage-specific Catalan breast cancer survival functions from scarce Catalan survival data by adapting the age- and stage-specific US functions. Methods: Cubic splines were used to smooth data and obtain continuous hazard rate functions. After, we fitted a Poisson model to derive hazard ratios. The model included time as a covariate. Then the hazard ratios were applied to US survival functions detailed by age and stage to obtain Catalan estimations. Results: We started estimating the hazard ratios for Catalonia versus the USA before and after the introduction of screening. The hazard ratios were then multiplied by the age- and stage-specific breast cancer hazard rates from the USA to obtain the Catalan hazard rates. We also compared breast cancer survival in Catalonia and the USA in two time periods, before cancer control interventions (USA 1975–79, Catalonia 1980–89) and after (USA and Catalonia 1990–2001). Survival in Catalonia in the 1980–89 period was worse than in the USA during 1975–79, but the differences disappeared in 1990–2001. Conclusion: Our results suggest that access to better treatments and quality of care contributed to large improvements in survival in Catalonia. On the other hand, we obtained detailed breast cancer survival functions that will be used for modeling the effect of screening and adjuvant treatments in Catalonia

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Quality management Self-evaluation of the organisation Citizens/customers satisfaction Impact on society evaluation Key performance evaluation Good practices comparison (Benchmarking) Continuous improvement In professional environments, when quality assessment of museums is discussed, one immediately thinks of the honourableness of the directors and curators, the erudition and specialisation of knowledge, the diversity of the gathered material and study of the collections, the collections conservation methods and environmental control, the regularity and notoriety of the exhibitions and artists, the building’s architecture and site, the recreation of environments, the museographic equipment design. We admit that the roles and attributes listed above can contribute to the definition of a specificity of museological good practice within a hierarchised functional perspective (the museum functions) and for the classification of museums according to a scale, validated between peers, based on “installed” appreciation criteria, enforced from above downwards, according to the “prestige” of the products and of those who conceive them, but that say nothing about the effective satisfaction of the citizen/customers and the real impact on society. There is a lack of evaluation instruments that would give us a return of all that the museum is and represents in contemporary society, focused on being and on the relation with the other, in detriment of the ostentatious possession and of the doing in order to meet one’s duties. But it is only possible to evaluate something by measurement and comparison, on the basis of well defined criteria, from a common grid, implicating all of the actors in the self-evaluation, in the definition of the aims to fulfil and in the obtaining of results.

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This study investigates possible vestibular dysfunctions in the deaf using a typical clinical assessment battery and discerns whether there is a trend between these disorders in meningitic children as compared to children with unknown origins of deafness.

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This paper discusses the diagnostic battery of the CELF in terms of construct validity and in administration of subtests.

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A new spectral-based approach is presented to find orthogonal patterns from gridded weather/climate data. The method is based on optimizing the interpolation error variance. The optimally interpolated patterns (OIP) are then given by the eigenvectors of the interpolation error covariance matrix, obtained using the cross-spectral matrix. The formulation of the approach is presented, and the application to low-dimension stochastic toy models and to various reanalyses datasets is performed. In particular, it is found that the lowest-frequency patterns correspond to largest eigenvalues, that is, variances, of the interpolation error matrix. The approach has been applied to the Northern Hemispheric (NH) and tropical sea level pressure (SLP) and to the Indian Ocean sea surface temperature (SST). Two main OIP patterns are found for the NH SLP representing respectively the North Atlantic Oscillation and the North Pacific pattern. The leading tropical SLP OIP represents the Southern Oscillation. For the Indian Ocean SST, the leading OIP pattern shows a tripole-like structure having one sign over the eastern and north- and southwestern parts and an opposite sign in the remaining parts of the basin. The pattern is also found to have a high lagged correlation with the Niño-3 index with 6-months lag.