969 resultados para Local Partial Likelihood
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Feature vectors can be anything from simple surface normals to more complex feature descriptors. Feature extraction is important to solve various computer vision problems: e.g. registration, object recognition and scene understanding. Most of these techniques cannot be computed online due to their complexity and the context where they are applied. Therefore, computing these features in real-time for many points in the scene is impossible. In this work, a hardware-based implementation of 3D feature extraction and 3D object recognition is proposed to accelerate these methods and therefore the entire pipeline of RGBD based computer vision systems where such features are typically used. The use of a GPU as a general purpose processor can achieve considerable speed-ups compared with a CPU implementation. In this work, advantageous results are obtained using the GPU to accelerate the computation of a 3D descriptor based on the calculation of 3D semi-local surface patches of partial views. This allows descriptor computation at several points of a scene in real-time. Benefits of the accelerated descriptor have been demonstrated in object recognition tasks. Source code will be made publicly available as contribution to the Open Source Point Cloud Library.
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This paper proves that every zero of any n th , n ≥ 2, partial sum of the Riemann zeta function provides a vector space of basic solutions of the functional equation f(x)+f(2x)+⋯+f(nx)=0,x∈R . The continuity of the solutions depends on the sign of the real part of each zero.
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This paper proves that the real projection of each simple zero of any partial sum of the Riemann zeta function ζn(s):=∑nk=11ks,n>2 , is an accumulation point of the set {Res : ζ n (s) = 0}.
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In this paper, we introduce a formula for the exact number of zeros of every partial sum of the Riemann zeta function inside infinitely many rectangles of the critical strips where they are situated.
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When in 2012 China approached the countries of Central and Eastern Europe (CEE) with a proposal of cooperation in the ‘16+1’ formula, it declared it was willing to meet the needs of CEE countries. Beijing had been aware of the political importance of the problem of trade deficit (which has been ongoing for years) and launched cooperation with the governments of 16 CEE countries to boost imports from these states. The years 2011–2014 brought an improvement in the balance of trade between China and: Hungary, Latvia, the Czech Republic, Romania, Bulgaria and Croatia. The remaining ten CEE countries recorded an increase in their trade deficits. Changes in CEE countries’ balance of trade with China resulted only slightly from political actions. Instead, they were due to the macroeconomic situation and to a deterioration of the debt crisis in the EU which, for example, caused a decline in the import of Chinese goods in some of these countries. Multilateral trade cooperation was successfully developed in the entire region only in the agricultural and food production sector – the area of greatest interest to China. The pace of bilateral cooperation with specific countries varied, with the fastest being Poland, Latvia, Romania, Hungary and Bulgaria. Actions by governments of CEE countries resulted in Chinese market opening up to hundreds of local companies which, in turn, translated into an increase in the volume of foodstuffs sold by ‘the 16’ to China from US$ 137 million in 2011 to US$ 400 million in 2014. The success achieved in the agricultural and food production sector has demonstrated the effectiveness of trade cooperation in the ‘16+1’ formula. It is, however, insufficient to generate a significant improvement of the trade balance. At present, the sector’s share in the total volume of goods sold to China by CEE states is a mere 3.7%, and any reduction of the trade deficit would require long-term and more comprehensive solutions still to be implemented by the governments of individual CEE states.
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Thesis (Ph.D.)--University of California, Berkeley, 1922.
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Background: Sentinel node biopsy (SNB) is being increasingly used but its place outside randomized trials has not yet been established. Methods: The first 114 sentinel node (SN) biopsies performed for breast cancer at the Princess Alexandra Hospital from March 1999 to June 2001 are presented. In 111 cases axillary dissection was also performed, allowing the accuracy of the technique to be assessed. A standard combination of preoperative lymphoscintigraphy, intraoperative gamma probe and injection of blue dye was used in most cases. Results are discussed in relation to the risk and potential consequences of understaging. Results: Where both probe and dye were used, the SN was identified in 90% of patients. A significant number of patients were treated in two stages and the technique was no less effective in patients who had SNB performed at a second operation after the primary tumour had already been removed. The interval from radioisotope injection to operation was very wide (between 2 and 22 h) and did not affect the outcome. Nodal metastases were present in 42 patients in whom an SN was found, and in 40 of these the SN was positive, giving a false negative rate of 4.8% (2/42), with the overall percentage of patients understaged being 2%. For this particular group as a whole, the increased risk of death due to systemic therapy being withheld as a consequence of understaging (if SNB alone had been employed) is estimated at less than 1/500. The risk for individuals will vary depending on other features of the particular primary tumour. Conclusion: For patients who elect to have the axilla staged using SNB alone, the risk and consequences of understaging need to be discussed. These risks can be estimated by allowing for the specific surgeon's false negative rate for the technique, and considering the likelihood of nodal metastases for a given tumour. There appears to be no disadvantage with performing SNB at a second operation after the primary tumour has already been removed. Clearly, for a large number of patients, SNB alone will be safe, but ideally participation in randomized trials should continue to be encouraged.
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Background: The purpose of the present study was to compare the effectiveness of three burns dressings (TransCyte, a bio-engineered skin substitute; Biobrane; and Silvazine cream (silver sulphadiazine and 0.2% chlorhexidine)), in treating children with partial-thickness burns. The primary objective was to determine the days until greater than or equal to90% re-epithelialization. The secondary objectives were to evaluate the number of wounds requiring autografting and the number of dressing changes/local wound care required. Methods: Study wounds were identified on each patient and the patients were randomized to receive TransCyte or Biobrane or Silvazine. Assessment of study wound closure began at 2 days after treatment and continued at least every other day thereafter until the wounds re-epithelialized or were autografted. A laser Doppler imaging system was used as an adjunct to assessing the depth of the burn. Results: Thirty-three patients with 58 wound sites enrolled in the study (TransCyte, n = 20, Biobrane, n = 17; Silvazine, n = 21). Mean time to re-epithelialization was 7.5 days for TransCyte, 9.5 days for Biobrane, and 11.2 days for Silvazine. The number of wounds requiring autografting were 5/21 (24%) for Silvazine, 3/17 (17%) for Biobrane, and 1/20 (5%) for TransCyte. Conclusions: When used in partial-thickness burns in children, TransCyte promotes fastest re-epithelialization and required less overall dressings then Biobrane or Silvazine. Patients who received Silvazine or Biobrane require more autografting than those treated with TransCyte.
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In the analysis and prediction of many real-world time series, the assumption of stationarity is not valid. A special form of non-stationarity, where the underlying generator switches between (approximately) stationary regimes, seems particularly appropriate for financial markets. We introduce a new model which combines a dynamic switching (controlled by a hidden Markov model) and a non-linear dynamical system. We show how to train this hybrid model in a maximum likelihood approach and evaluate its performance on both synthetic and financial data.
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This study examines the effect of budgetary participation on departmental performance via budget adequacy, organisational commitment and role ambiguity. The responses of 108 budget preparers and budget users drawn from a cross-section of Malaysian local authorities, to a questionnaire survey were analysed by using mediation analysis, path analysis and Pearson Product-Moment Correlation technique. The results suggest that budget adequacy, organisational commitment, and role ambiguity are important links in the process. The results of this study suggest that the relationship between budget participation and departmental performance is statistically, significantly, positively and marginally correlated. Of more interest was the finding that budget adequacy, organisational commitment, and role ambiguity are important intervening variables in the relationship between budget participation and departmental performance. The test for mediation effect, demonstrated that budget adequacy, organisational commitment, and role ambiguity had partially mediated the relationship of budget participation and departmental performance. These three variables act as partial mediators when they significantly reduced or decreased the path coefficient of budget participation and departmental performance rather than eliminating the relationship. Furthermore, the test for direct and indirect effect of budget participation on departmental performance, suggests that budget participation predicted or affected departmental performance more strongly in the indirect way than it did in a direct way. This suggests that, even though the correlation between budget participation and departmental performance was significant, the path interpretation suggests that the correlation arose because budget participation was correlated with other variables that have direct effect upon departmental performance not budget participation itself directly predicted departmental performance. Therefore, there is enough evidence to suggest that budget participation of budget preparers and budget users affects departmental performance of Malaysian local authorities indirectly via budget adequacy, organisational commitment and role ambiguity. Among the indirect effects, the link between budget participation, budget adequacy, organisational commitment, role ambiguity and departmental performance may be the most important in term of this study’s contribution. The decomposition of the observed correlation between budget participation, budget adequacy, organisational commitment and role ambiguity showed that budget 3 participation of budget preparers and budget users of Malaysian local authorities in the budget setting has direct effect on budget adequacy, organisational commitment and role ambiguity. Budget adequacy and organisational commitment was directly related. However, the relationship of role ambiguity and organisational commitment in this study was indirectly related. This suggests that participation of budget preparers and budget users in the budget setting of Malaysian local authorities lead to decrease role ambiguity that provide adequate budgetary supports, which lead to increase organisational commitment and thus enhance departmental performance. In relation to the strength of the relationships of the variables undertaken for the study, the overall relationships between variables are significant and positively related except that of role ambiguity relationship. The relationships of role ambiguity with budget participation, budget adequacy, organisational performance and departmental performance are negatively related.
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The paper has been presented at the 12th International Conference on Applications of Computer Algebra, Varna, Bulgaria, June, 2006
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By contrast to the far-reaching devolution settlements elsewhere in the UK, political agreement on the governance of England outside London remains unsettled. There is cross- party consensus on the need to 'decentre down' authority to regions and localities, but limited agreement on how this should be achieved. This paper explores the welter of initiatives adopted by the recent Labour government that were ostensibly designed to make the meso-level of governance more coherent, accountable and responsive to meeting territorial priorities. Second, it explores the current Conservative-Liberal Democrat Coalition's programme of reform that involves the elimination of Labour's regional institutional architecture and is intended to restore powers to local government and communities and promote local authority co-operation around sub-regions. Labour's reforms were ineffective in achieving any substantial transfer of authority away from Whitehall and, given the Coalition's plans to cut public expenditure, the likelihood of any significant recalibration in central-local relations also appears improbable. © 2012 Copyright Taylor and Francis Group, LLC.
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My dissertation has three chapters which develop and apply microeconometric tech- niques to empirically relevant problems. All the chapters examines the robustness issues (e.g., measurement error and model misspecification) in the econometric anal- ysis. The first chapter studies the identifying power of an instrumental variable in the nonparametric heterogeneous treatment effect framework when a binary treat- ment variable is mismeasured and endogenous. I characterize the sharp identified set for the local average treatment effect under the following two assumptions: (1) the exclusion restriction of an instrument and (2) deterministic monotonicity of the true treatment variable in the instrument. The identification strategy allows for general measurement error. Notably, (i) the measurement error is nonclassical, (ii) it can be endogenous, and (iii) no assumptions are imposed on the marginal distribution of the measurement error, so that I do not need to assume the accuracy of the measure- ment. Based on the partial identification result, I provide a consistent confidence interval for the local average treatment effect with uniformly valid size control. I also show that the identification strategy can incorporate repeated measurements to narrow the identified set, even if the repeated measurements themselves are endoge- nous. Using the the National Longitudinal Study of the High School Class of 1972, I demonstrate that my new methodology can produce nontrivial bounds for the return to college attendance when attendance is mismeasured and endogenous.
The second chapter, which is a part of a coauthored project with Federico Bugni, considers the problem of inference in dynamic discrete choice problems when the structural model is locally misspecified. We consider two popular classes of estimators for dynamic discrete choice models: K-step maximum likelihood estimators (K-ML) and K-step minimum distance estimators (K-MD), where K denotes the number of policy iterations employed in the estimation problem. These estimator classes include popular estimators such as Rust (1987)’s nested fixed point estimator, Hotz and Miller (1993)’s conditional choice probability estimator, Aguirregabiria and Mira (2002)’s nested algorithm estimator, and Pesendorfer and Schmidt-Dengler (2008)’s least squares estimator. We derive and compare the asymptotic distributions of K- ML and K-MD estimators when the model is arbitrarily locally misspecified and we obtain three main results. In the absence of misspecification, Aguirregabiria and Mira (2002) show that all K-ML estimators are asymptotically equivalent regardless of the choice of K. Our first result shows that this finding extends to a locally misspecified model, regardless of the degree of local misspecification. As a second result, we show that an analogous result holds for all K-MD estimators, i.e., all K- MD estimator are asymptotically equivalent regardless of the choice of K. Our third and final result is to compare K-MD and K-ML estimators in terms of asymptotic mean squared error. Under local misspecification, the optimally weighted K-MD estimator depends on the unknown asymptotic bias and is no longer feasible. In turn, feasible K-MD estimators could have an asymptotic mean squared error that is higher or lower than that of the K-ML estimators. To demonstrate the relevance of our asymptotic analysis, we illustrate our findings using in a simulation exercise based on a misspecified version of Rust (1987) bus engine problem.
The last chapter investigates the causal effect of the Omnibus Budget Reconcil- iation Act of 1993, which caused the biggest change to the EITC in its history, on unemployment and labor force participation among single mothers. Unemployment and labor force participation are difficult to define for a few reasons, for example, be- cause of marginally attached workers. Instead of searching for the unique definition for each of these two concepts, this chapter bounds unemployment and labor force participation by observable variables and, as a result, considers various competing definitions of these two concepts simultaneously. This bounding strategy leads to partial identification of the treatment effect. The inference results depend on the construction of the bounds, but they imply positive effect on labor force participa- tion and negligible effect on unemployment. The results imply that the difference- in-difference result based on the BLS definition of unemployment can be misleading
due to misclassification of unemployment.
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Los periodistas de Burgos del siglo XIX desempeñaron un importante protagonismo en la defensa del patrimonio histórico artístico. En un momento en el que la protección de los monumentos no estaba garantizada ni regulada, estos profesionales demostraron con su pluma tener una mentalidad adelantada a la de su tiempo y defendieron la necesidad de mantener, proteger y rehabilitar los grandes y pequeños monumentos. Su intervención y sus denuncias constituyen una demostración de la importancia del periodismo, y en especial del periodismo local.
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Through the tough economic and social situation and the lack of values that has been experienced in recent years, local governments especially in Greece, Portugal, Italy and Spain have been forced to strongly consider the structure and size of their public sector. Despite some initiative to reduce the number of municipalities and provinces, little substantive progress has been made in improving the management of the local public Administration during this crisis. In this study a territorial administrative reorganization is proposed as a strategy to optimize the structure of local government, analyzing the Spanish situation in general, and an autonomous community in particular.