Search results

This paper aims to propose a general and rigorous study on the propagation property of invariant errors for the model conversion of state estimation problems with discrete group affine systems.

The evolution and operation properties of error propagation model of discrete group affine physical systems are investigated in detail. The general expressions of the propagation properties are proposed together with the rigorous proof and analysis which provide a deeper insight and are beneficial to the control and estimation of discrete group affine systems.

The investigation on the state independency and log-linearity of invariant errors for discrete group affine systems are presented in this work, and it is pivotal for the convergence and stability of estimation and control of physical systems in engineering practice. The general expressions of the propagation properties are proposed together with the rigorous proof and analysis.

An example application to the attitude dynamics of a rigid body together with the attitude estimation problem is used to illustrate the theoretical results.

The mathematical proof and analysis of the state independency and log-linearity property are the unique and original contributions of this work.

In Hong Kong, a balcony is often perceived as a “green” provision in modern residential buildings. However, how the market values the benefits of balconies is seldom studied due to the difficulty in separating such benefits from other associated effects such as view enjoyment and security concerns. This paper attempts to study the implicit value of a balcony, the green effects of balconies on the prices of residential properties, and the effect of security concerns on balconies situated on lower floors. A sample of transactions in a private housing estate in Hong Kong has been studied. The sample contains apartments with and without balconies. A balcony is found to have a positive effect on the value of a property irrespective of the quality of the view. The negative effects of air and noise pollution on property prices are also found to be highly significant. Although security concerns are found on the low stories of a building, the provision of a balcony does not aggravate the hazard. Finally, the log‐linearity assumption in the empirical price model is relaxed by applying the Box‐Cox transformation to the continuous variables.

Baltagi and Li (2001) derived Lagrangian multiplier tests to jointly test for functional form and spatial error correlation. This companion paper derives Lagrangian multiplier tests to jointly test for functional form and spatial lag dependence. In particular, this paper tests for linear or log-linear models with no spatial lag dependence against a more general Box-Cox model with spatial lag dependence. Conditional LM tests are also derived which test for (i) zero spatial lag dependence conditional on an unknown Box-Cox functional form, as well as, (ii) linear or log-linear functional form given spatial lag dependence. In addition, modified Rao-Score tests are also derived that guard against local misspecification. The performance of these tests are investigated using Monte Carlo experiments.

The Bradford law is explored theoretically by means of a very mixed Poisson model which, it is claimed, elucidates the uncertainties surrounding the law and its applications. It is argued that Bradford succeeded in formulating an empirical regularity which has pure and hybrid forms but that all the variants can be subsumed under a simple logarithmic law which, for reasons explained, escapes exact expression in conventional frequency terms. The theoretical aspects discussed include the hybridity of form, estimations, sampling problems, the stability of ranks, homogeneity of data, and tests of significance. Some numerical examples, some simulated and some drawn from social contexts outside bibliography, are used both to illustrate theoretical issues and also to indicate the wide generality of the Bradford law. Possible applications and developments of the theory are indicated.

This paper uses the gravity model to examine the impact of the Common Market for Eastern and Southern Africa on the flow of Kenya's exports. The empirical results suggest that COMESA has the effect of trade creation. No evidence for trade diversion is found. Accordingly, COMESA has helped to improve Kenya's export performance and, in turn, assisted in the effort to achieve the Millennium Development Goals. The results also show that nominal GDP of importing countries, distance, adjacency, and common official language have a statistically significant impact on the flow of Kenya's exports.

Patent data have been exploited to track invention and international technology diffusion. We review evidence on research activity, international patenting, and income differences across countries. Guided by that evidence, we construct a model of ideas in the world economy that includes the decision of whether and where to patent them. The model makes precise connections between international patent statistics and cross-country differences in innovation, technology diffusion, market size, and strength of patent protection. We use it to organize our discussion of existing empirical studies, which typically focus on one of five core relationships: (i) national pools of knowledge and international spillovers from basic research; (ii) aggregate productivity and international technology diffusion from applied research; (iii) international patenting and the production of ideas, international diffusion, market sizes, and intellectual property regimes; (iv) the value of ideas and diffusion, market sizes, and the intellectual property regimes; or (v) investment in research and research productivity, the cost of research, and the value of ideas. While distinguishing between these five relationships proves useful, they are, of course, logically intertwined. Taking these interconnections into account will contribute to the goal of building a quantitative model of the creation, diffusion, and adoption of ideas in the global economy.

The purpose of this paper is to investigate trends in patient hospital quality perceptions between 1999 and 2010.

Original data from 11 cross-sectional surveys carried out in a French single university hospital were analyzed. Based on responses to a 29-item survey instrument, overall and subscale perception scores (range 0-10) were computed covering six key hospital care quality dimensions.

Of 16,516 surveyed patients, 10,704 (64.8 percent) participated in the study. The median overall patient perception score decreased from 7.86 (25th-75th percentiles, 6.67-8.85) in 1999 to 7.82 (25th-75th percentiles, 6.67-8.74) in 2010 (p for trend <0.001). A decreasing trend was observed for the living arrangement subscale score (from 7.78 in 1999 to 7.50 in 2010, p for trend <0.001). Food service and room comfort perceptions deteriorated over the study period while patients increasingly reported better explanations before being examined.

Patient perception scores may disguise divergent judgments on different care aspect while individual items highlight specific areas with room for improvement.

Despite growing pressure on healthcare expenditure, this single-center study showed only modest reduction in patients’ hospital-care perceptions in the 2000s.

The paper measures the degree of bank competition in Indian banking over the period 1996–2016. Using bank-level annual data, we revisit the case of banking competitiveness during the prefinancial and postfinancial crisis and examine whether the global financial crisis alters the level of bank competition in India. Additionally, this paper addresses the misspecification issues associated with the widely used Panzar–Rosse model in Indian banking context.

We apply Panzar and Rosse (1987) H-statistic and evaluate the degree of bank competition by estimating the extent to which changes in input prices are reflected in revenues earned by banks. Subsequently, we link this measure of competitiveness to a number of structural indicators (HHI and CRn) to examine the structure-conduct-performance hypothesis, which assumes that a concentrated banking system can impair competition. The simple panel regression model was used to handle the empirical estimations.

findings reveal that the Indian banking system operates under competitive conditions and earns revenues as if under the monopolistic competition. We also find evidence that Indian banks are competitive, even under a concentrated market structure. This observation runs, in contrary, to the prediction of the structure–conduct–performance hypothesis. The findings also indicate the differences in the estimated H-statistic value after considering the misspecifications of the P–R model.

From policy perspectives, policymakers should focus more on maintaining an optimal level of bank competition by mitigating entry restrictions, exercising less consolidation and withdrawing overregulation from banking activities. A competitive banking industry ensures both efficiency and stability.

A competitive banking sector by lowering interest rates margin provides easier access to finance to both households and small and medium enterprises (SMEs).

This is the only study that addresses the misspecification of the P–R model while assessing competition in Indian banking and provides a thorough understanding of the role of concentration on bank competition.