Purpose: To study the clinical characteristics, therapeutic efficacy and investigate pro-gnostic factors of endogenous endophthalmitis. Methods: Twenty-eight cases (28 eyes) of endogenous endophthalmitis were surveyed...Purpose: To study the clinical characteristics, therapeutic efficacy and investigate pro-gnostic factors of endogenous endophthalmitis. Methods: Twenty-eight cases (28 eyes) of endogenous endophthalmitis were surveyed retrospectively. The clinical characteristics, primary infection foci, predisposing systemic disease, complications, pathogens examination, therapeutic options and efficacy were analysed. Results: The endogenous endophthalmitis occurred more frequently in the right eye than in the left one. The respiratory tract was the most common primary foci. The positive rate of pathogens culture was higher in vitreous sample than that in other tissues. Cataract and retinal detachment were the common complications. The visual improvement and infection control were achieved in 13 eyes (46.43%). These 13 patients received treatment (3.77±2.49)days after onset of endophthalmitis being much earlier than that of others [(10.13±4.98)days, P=0.002]. The prognosis was relevant to the type of the disease. The anterior segment inflammation type(anterior type) had better prognosis than posterior segment inflammation type(posterior type) and that of inflammation in both parts(mix type) (P < 0.05). There were no significant relation between the prognosis and the age, predisposing systemic disease, vitreous antibiotic injection and vitrectomy (P > 0.05).Conclusions: Endogenous endophthalmitis is a vital ocular emergency. Early diagnosis and effective treatment combination with systemic and local antibiotics are of significant value. The anterior type is prone to have better outcome than the others.展开更多
This paper considers the estimate problem on the mean matrix of mixture of normals. In order to evaluate estimators of the mean matrix, a fundamental frame of Φ-(general) decision problem is established. Under the fr...This paper considers the estimate problem on the mean matrix of mixture of normals. In order to evaluate estimators of the mean matrix, a fundamental frame of Φ-(general) decision problem is established. Under the frame, a class of Φ-minimax estimators are constructed.展开更多
Climate change detection, attribution, and prediction were studied for the surface temperature in the Northeast Asian region using NCEP/NCAR reanalysis data and three coupled-model simulations from ECHAM4/OPYC3, HadCM...Climate change detection, attribution, and prediction were studied for the surface temperature in the Northeast Asian region using NCEP/NCAR reanalysis data and three coupled-model simulations from ECHAM4/OPYC3, HadCM3, and CCCma GCMs (Canadian Centre for Climate Modeling and Analysis general circulation model). The Bayesian fingerprint approach was used to perform the detection and attribution test for the anthropogenic climate change signal associated with changes in anthropogenic carbon dioxide (CO2) and sulfate aerosol (SO42-) concentrations for the Northeast Asian temperature. It was shown that there was a weak anthropogenic climate change signal in the Northeast Asian temperature change. The relative contribution of CO2 and SO42- effects to total temperature change in Northeast Asia was quantified from ECHAM4/OPYC3 and CCCma GCM simulations using analysis of variance. For the observed temperature change for the period of 1959-1998, the CO2 effect contributed 10%-21% of the total variance and the direct cooling effect of SO42- played a less important role (0%-7%) than the CO2 effect. The prediction of surface temperature change was estimated from the second CO2+SO42- scenario run of ECHAM4/OPYC3 which has the least error in the simulation of the present-day temperature field near the Korean Peninsula. The result shows that the area-mean surface temperature near the Korean Peninsula will increase by about 1.1° by the 2040s relative to the 1990s.展开更多
The detection of the configuration of parameters is one of the most important problems in statistical studies. It is well known that the Akaike’s information criterion (AIC) is a key tool for this problem
In this paper we consider a Markov chain model in an ATM network, which has been studied by Dag and Stavrakakis. On the basis of the iterative formulas obtained by Dag and Stavrakakis, we obtain the explicit analytica...In this paper we consider a Markov chain model in an ATM network, which has been studied by Dag and Stavrakakis. On the basis of the iterative formulas obtained by Dag and Stavrakakis, we obtain the explicit analytical expression of the transition probability matrix. It is very simple to calculate the transition probabilities of the Markov chain by these expressions. In addition, we obtain some results about the structure of the transition probability matrix, which are helpful in numerical calculation and theoretical analysis.展开更多
In this paper we study urn model, using some available estimates of successes probabilities, and adding particle parameter, we establish adaptive models. We obtain some strong convergence theorems, rates of convergenc...In this paper we study urn model, using some available estimates of successes probabilities, and adding particle parameter, we establish adaptive models. We obtain some strong convergence theorems, rates of convergence, asymptotic normality of components in the urn, and estimates. With these asymptotical results, we show that the adaptive designs given in this paper are asymptotically optimal designs.展开更多
The authors derive laws of the iterated logarithm for kernel estimator of regression function based on directional data. The results are distribution free in the sense that they are true for all distributions of desig...The authors derive laws of the iterated logarithm for kernel estimator of regression function based on directional data. The results are distribution free in the sense that they are true for all distributions of design variable.展开更多
In this paper, the Schwarz Information Criterion (SIC) is used to detect the change points in polynomial regression models. Switching quadratic regression models with same amount of model deviation and switching polyn...In this paper, the Schwarz Information Criterion (SIC) is used to detect the change points in polynomial regression models. Switching quadratic regression models with same amount of model deviation and switching polynomial regression models with different amount of model deviation for different segments of regression are considered. The number of separate regimes and their corresponding regression orders are assume to be known. The method is then applied to cable data sets and the change points are successfully detected.展开更多
Consider the partitioned linear regression model and its four reduced linear models, where y is an n × 1 observable random vector with E(y) = Xβ and dispersion matrix Var(y) = σ2 V, where σ2 is an unknown pos...Consider the partitioned linear regression model and its four reduced linear models, where y is an n × 1 observable random vector with E(y) = Xβ and dispersion matrix Var(y) = σ2 V, where σ2 is an unknown positive scalar, V is an n × n known symmetric nonnegative definite matrix, X = (X 1 : X 2) is an n×(p+q) known design matrix with rank(X) = r ≤ (p+q), and β = (β′ 1: β′2 )′ with β1 and β2 being p×1 and q×1 vectors of unknown parameters, respectively. In this article the formulae for the differences between the best linear unbiased estimators of M 2 X 1β1under the model and its best linear unbiased estimators under the reduced linear models of are given, where M 2 = I -X 2 X 2 + . Furthermore, the necessary and sufficient conditions for the equalities between the best linear unbiased estimators of M 2 X 1β1 under the model and those under its reduced linear models are established. Lastly, we also study the connections between the model and its linear transformation model.展开更多
The authors establish the approximations to the distribution of M-estimates in a linear model by the bootstrap and the linear representation of bootstrap M-estimation, and prove that the approximation is valid in prob...The authors establish the approximations to the distribution of M-estimates in a linear model by the bootstrap and the linear representation of bootstrap M-estimation, and prove that the approximation is valid in probability 1. A simulation is made to show the effects of bootstrap approximation, randomly weighted approximation and normal approximation.展开更多
For partial linear model Y = X~τβ_0 + g_0(T) + ε with unknown β_0 ∈ R^dand an unknown smooth function g_0, this paper considers the Huber-Dutter estimators of β_0, scaleσ for the errors and the function g_0 res...For partial linear model Y = X~τβ_0 + g_0(T) + ε with unknown β_0 ∈ R^dand an unknown smooth function g_0, this paper considers the Huber-Dutter estimators of β_0, scaleσ for the errors and the function g_0 respectively, in which the smoothing B-spline function isused. Under some regular conditions, it is shown that the Huber-Dutter estimators of β_0 and σ areasymptotically normal with convergence rate n^(-1/2) and the B-spline Huber-Dutter estimator of g_0achieves the optimal convergence rate in nonparametric regression. A simulation study demonstratesthat the Huber-Dutter estimator of β_0 is competitive with its M-estimator without scale parameterand the ordinary least square estimator. An example is presented after the simulation study.展开更多
Abstract In this paper a reversible Markov process as a chemical polymers reaction of two types of monomers is defined. By analyzing the partition functions of the process we obtain three different distributions of th...Abstract In this paper a reversible Markov process as a chemical polymers reaction of two types of monomers is defined. By analyzing the partition functions of the process we obtain three different distributions of the average molecular weight, depending on the value of strength of the fragmentation reaction, and prove that a gelation of the process will occur in the thermodynamic limit.展开更多
In this paper, two kinds of Kullback-Leibler criteria with appropriate constraints are proposed to construct empirical likelihood confidence intervals for the mean of right censored data. It is shown that one of the c...In this paper, two kinds of Kullback-Leibler criteria with appropriate constraints are proposed to construct empirical likelihood confidence intervals for the mean of right censored data. It is shown that one of the criteria is equivalent to Adimari’s(1997) procedure, and the other shares the same asymptotic behavior.展开更多
We consider the maximum likelihood estimator of the unknown parameter in aclass of nonstationary diffusion processes. We give further a precise estimate for the error of theestimator.
文摘Purpose: To study the clinical characteristics, therapeutic efficacy and investigate pro-gnostic factors of endogenous endophthalmitis. Methods: Twenty-eight cases (28 eyes) of endogenous endophthalmitis were surveyed retrospectively. The clinical characteristics, primary infection foci, predisposing systemic disease, complications, pathogens examination, therapeutic options and efficacy were analysed. Results: The endogenous endophthalmitis occurred more frequently in the right eye than in the left one. The respiratory tract was the most common primary foci. The positive rate of pathogens culture was higher in vitreous sample than that in other tissues. Cataract and retinal detachment were the common complications. The visual improvement and infection control were achieved in 13 eyes (46.43%). These 13 patients received treatment (3.77±2.49)days after onset of endophthalmitis being much earlier than that of others [(10.13±4.98)days, P=0.002]. The prognosis was relevant to the type of the disease. The anterior segment inflammation type(anterior type) had better prognosis than posterior segment inflammation type(posterior type) and that of inflammation in both parts(mix type) (P < 0.05). There were no significant relation between the prognosis and the age, predisposing systemic disease, vitreous antibiotic injection and vitrectomy (P > 0.05).Conclusions: Endogenous endophthalmitis is a vital ocular emergency. Early diagnosis and effective treatment combination with systemic and local antibiotics are of significant value. The anterior type is prone to have better outcome than the others.
文摘This paper considers the estimate problem on the mean matrix of mixture of normals. In order to evaluate estimators of the mean matrix, a fundamental frame of Φ-(general) decision problem is established. Under the frame, a class of Φ-minimax estimators are constructed.
文摘Climate change detection, attribution, and prediction were studied for the surface temperature in the Northeast Asian region using NCEP/NCAR reanalysis data and three coupled-model simulations from ECHAM4/OPYC3, HadCM3, and CCCma GCMs (Canadian Centre for Climate Modeling and Analysis general circulation model). The Bayesian fingerprint approach was used to perform the detection and attribution test for the anthropogenic climate change signal associated with changes in anthropogenic carbon dioxide (CO2) and sulfate aerosol (SO42-) concentrations for the Northeast Asian temperature. It was shown that there was a weak anthropogenic climate change signal in the Northeast Asian temperature change. The relative contribution of CO2 and SO42- effects to total temperature change in Northeast Asia was quantified from ECHAM4/OPYC3 and CCCma GCM simulations using analysis of variance. For the observed temperature change for the period of 1959-1998, the CO2 effect contributed 10%-21% of the total variance and the direct cooling effect of SO42- played a less important role (0%-7%) than the CO2 effect. The prediction of surface temperature change was estimated from the second CO2+SO42- scenario run of ECHAM4/OPYC3 which has the least error in the simulation of the present-day temperature field near the Korean Peninsula. The result shows that the area-mean surface temperature near the Korean Peninsula will increase by about 1.1° by the 2040s relative to the 1990s.
文摘The detection of the configuration of parameters is one of the most important problems in statistical studies. It is well known that the Akaike’s information criterion (AIC) is a key tool for this problem
基金This work is supported by the National Key Project of China(No 970211017,the National Natural Science Foundation of China(No,10271102)and Hebei Province Doctoral Foundation(No.2002131)
文摘In this paper we consider a Markov chain model in an ATM network, which has been studied by Dag and Stavrakakis. On the basis of the iterative formulas obtained by Dag and Stavrakakis, we obtain the explicit analytical expression of the transition probability matrix. It is very simple to calculate the transition probabilities of the Markov chain by these expressions. In addition, we obtain some results about the structure of the transition probability matrix, which are helpful in numerical calculation and theoretical analysis.
基金This work is supported by the National Science Foundation (No.10271001) of China.
文摘In this paper we study urn model, using some available estimates of successes probabilities, and adding particle parameter, we establish adaptive models. We obtain some strong convergence theorems, rates of convergence, asymptotic normality of components in the urn, and estimates. With these asymptotical results, we show that the adaptive designs given in this paper are asymptotically optimal designs.
基金Project supported by the National Natural Science Foundation of China (Nos. 19631040 19971085), the Doctoral Program Foundatio
文摘The authors derive laws of the iterated logarithm for kernel estimator of regression function based on directional data. The results are distribution free in the sense that they are true for all distributions of design variable.
文摘In this paper, the Schwarz Information Criterion (SIC) is used to detect the change points in polynomial regression models. Switching quadratic regression models with same amount of model deviation and switching polynomial regression models with different amount of model deviation for different segments of regression are considered. The number of separate regimes and their corresponding regression orders are assume to be known. The method is then applied to cable data sets and the change points are successfully detected.
基金supported by the National Natural Science Foundation of ChinaTian Yuan Special Foundation (No.10226024)Postdoctoral Foundation of China and Lab.of Math.for Nonlinear Sciences at Fudan Universitysupported in part by The International Organizing Committee and The Local Organizing Committee at the University of Tampere for this Workshopsupported in part by an NSF grant of China
文摘Consider the partitioned linear regression model and its four reduced linear models, where y is an n × 1 observable random vector with E(y) = Xβ and dispersion matrix Var(y) = σ2 V, where σ2 is an unknown positive scalar, V is an n × n known symmetric nonnegative definite matrix, X = (X 1 : X 2) is an n×(p+q) known design matrix with rank(X) = r ≤ (p+q), and β = (β′ 1: β′2 )′ with β1 and β2 being p×1 and q×1 vectors of unknown parameters, respectively. In this article the formulae for the differences between the best linear unbiased estimators of M 2 X 1β1under the model and its best linear unbiased estimators under the reduced linear models of are given, where M 2 = I -X 2 X 2 + . Furthermore, the necessary and sufficient conditions for the equalities between the best linear unbiased estimators of M 2 X 1β1 under the model and those under its reduced linear models are established. Lastly, we also study the connections between the model and its linear transformation model.
基金supported by Fund of 211 Program of SHUFEFund of Educational Committee of Shanghai
文摘The authors establish the approximations to the distribution of M-estimates in a linear model by the bootstrap and the linear representation of bootstrap M-estimation, and prove that the approximation is valid in probability 1. A simulation is made to show the effects of bootstrap approximation, randomly weighted approximation and normal approximation.
基金Supported by The National Natural Science Foundation of China (No. 10231030 )Beijing Normal University Youth Foundation (No. 104951).
文摘For partial linear model Y = X~τβ_0 + g_0(T) + ε with unknown β_0 ∈ R^dand an unknown smooth function g_0, this paper considers the Huber-Dutter estimators of β_0, scaleσ for the errors and the function g_0 respectively, in which the smoothing B-spline function isused. Under some regular conditions, it is shown that the Huber-Dutter estimators of β_0 and σ areasymptotically normal with convergence rate n^(-1/2) and the B-spline Huber-Dutter estimator of g_0achieves the optimal convergence rate in nonparametric regression. A simulation study demonstratesthat the Huber-Dutter estimator of β_0 is competitive with its M-estimator without scale parameterand the ordinary least square estimator. An example is presented after the simulation study.
基金Supported by the National Natural Sciences Foundation of China (No.19661003).
文摘Abstract In this paper a reversible Markov process as a chemical polymers reaction of two types of monomers is defined. By analyzing the partition functions of the process we obtain three different distributions of the average molecular weight, depending on the value of strength of the fragmentation reaction, and prove that a gelation of the process will occur in the thermodynamic limit.
基金The work is partially supported by the NSFof China(No:10071090) and the Chinese Academy of Sciences.
文摘In this paper, two kinds of Kullback-Leibler criteria with appropriate constraints are proposed to construct empirical likelihood confidence intervals for the mean of right censored data. It is shown that one of the criteria is equivalent to Adimari’s(1997) procedure, and the other shares the same asymptotic behavior.
基金Research partially supported by N.S.F.Grants DMS-0203823Doctoral Program Foundation of the Ministry of Education of China,Grant No.20020269015
文摘We consider the maximum likelihood estimator of the unknown parameter in aclass of nonstationary diffusion processes. We give further a precise estimate for the error of theestimator.