Suppose that the time series Xt satisfieswhere α0≥δ>0,αi≥0 for i=1,2,…,q;βi,i=1,…,p, are real numbers; p and q are the order of the model. The sequence {ξt};(0,1) and is independent of {hs,s≤t} for fixed ...Suppose that the time series Xt satisfieswhere α0≥δ>0,αi≥0 for i=1,2,…,q;βi,i=1,…,p, are real numbers; p and q are the order of the model. The sequence {ξt};(0,1) and is independent of {hs,s≤t} for fixed t. The above model is usually written as AR(p)-ARCH(q).We consider stationary series AR(p)-ARCH(q) model and assume the stationary field is θ0. We express this statement asH1:α1≥α2…≥αq,β1≥β2≥…≥βp and we consider an order restricted testing problem, which is to testH0:α1=α2=…=αq,β1=β2=…=βpagainst H1-H0. We derive the likelihood ratio (LR) test statistic and its asymptotic distri-展开更多
In this paper, we study a stationary AR(p)-ARCH(q) model with parameter vectors α and β. We propose a method for computing the maximum likelihood estimator (MLE) of parameters under the nonnegative restriction...In this paper, we study a stationary AR(p)-ARCH(q) model with parameter vectors α and β. We propose a method for computing the maximum likelihood estimator (MLE) of parameters under the nonnegative restriction. A similar method is also proposed for the case that the parameters are restricted by a simple order: α1≥α2≥…≥αq and β1≥β2≥…≥βp. The strong consistency of the above two estimators is discussed. Furthermore, we consider the problem of testing homogeneity of parameters against the simple order restriction. We give the likelihood ratio (LR) test statistic for the testing problem and derive its asymptotic null distribution.展开更多
In this paper,a statistical prediction problem under ordered location and scale parameters are considered.Double-shrinkage predictors are given which use all the available data and improve on single-shrinkage predicto...In this paper,a statistical prediction problem under ordered location and scale parameters are considered.Double-shrinkage predictors are given which use all the available data and improve on single-shrinkage predictors,and hence the best equivariant predictors.展开更多
A biased sampling algorithm for the restricted Boltzmann machine(RBM) is proposed, which allows generating configurations with a conserved quantity. To validate the method, a study of the short-range order in binary a...A biased sampling algorithm for the restricted Boltzmann machine(RBM) is proposed, which allows generating configurations with a conserved quantity. To validate the method, a study of the short-range order in binary alloys with positive and negative exchange interactions is carried out. The network is trained on the data collected by Monte–Carlo simulations for a simple Ising-like binary alloy model and used to calculate the Warren–Cowley short-range order parameter and other thermodynamic properties. We demonstrate that the proposed method allows us not only to correctly reproduce the order parameters for the alloy concentration at which the network was trained, but can also predict them for any other concentrations.展开更多
Collective cell migration is a coordinated movement of multi-cell systems essential for various processes throughout life.The collective motions often occur under spatial restrictions,hallmarked by the collective rota...Collective cell migration is a coordinated movement of multi-cell systems essential for various processes throughout life.The collective motions often occur under spatial restrictions,hallmarked by the collective rotation of epithelial cells confined in circular substrates.Here,we aim to explore how geometric shapes of confinement regulate this collective cell movement.We develop quantitative methods for cell velocity orientation analysis,and find that boundary cells exhibit stronger tangential ordering migration than inner cells in circular pattern.Furthermore,decreased tangential ordering movement capability of collective cells in triangular and square patterns are observed,due to the disturbance of cell motion at unsmooth corners of these patterns.On the other hand,the collective cell rotation is slightly affected by a convex defect of the circular pattern,while almost hindered with a concave defect,also resulting from different smoothness features of their boundaries.Numerical simulations employing cell Potts model well reproduce and extend experimental observations.Together,our results highlight the importance of boundary smoothness in the regulation of collective cell tangential ordering migration.展开更多
In recent years,the“power restriction”measures were taken in many localities,industrial electricity consumption was interrupted,mainly in the“two high”(high energy consumption and high pollutant emission)enterpris...In recent years,the“power restriction”measures were taken in many localities,industrial electricity consumption was interrupted,mainly in the“two high”(high energy consumption and high pollutant emission)enterprises.Take the“power restriction”event in 2021 as an example,this event affected a wide range of regions and disrupted people’s livelihood.It not only refers to the power switch and rationing measures taken by individual regions,but also includes differentiated policies implemented by over 20 provinces to limit power supply and industrial production.This paper investigated in detail and summarized the different requirements of power restriction across the country,through the comparison of annual growth rates of power generation and industrial added value,the comparison results of energy intensity,electricity production,power consumption and the industrial growth rate in each province are analyzed.Industrial enterprises and related industrial chains were most heavily affected by the“power restriction”event,mainly in steel,cement,electrolytic aluminum,industrial silicon,textile printing and dyeing,chemical fiber,chemical and other enterprises with high energy consumption and high pollutants emission.The measures to limit electricity will affect the normal production of enterprises to a certain extent,leading to not only the decrease of production efficiency,but also the increase of energy consumption and pollutant emission per unit product.Energy management measures such as differentiated electricity price have limited effect on the output of“two high”industrial products,and the economic leverage of differentiated electricity price is gradually being diluted by the price rise of end products.This paper analyzed the reasons and explored several key problems that need special attention.then recommended certain countermeasures for its appropriate application in the future.展开更多
The parameters of probability distributions under partial order restrictions are usually estimated by maximum likelihood estimates(MLE) and formulated as a maximization problem with a multimodal objective function sub...The parameters of probability distributions under partial order restrictions are usually estimated by maximum likelihood estimates(MLE) and formulated as a maximization problem with a multimodal objective function subject to partial order restrictions. In order to obtain the global optimal estimation of parameters, this paper presents a genetic algorithm and illustrates its effectiveness by some numerical examples.展开更多
For two normal populations with unknown means μi and variances σi2 > 0, i = 1,2, assume that there is a semi-order restriction between ratios of means and standard deviations and sample numbers of two normal popu...For two normal populations with unknown means μi and variances σi2 > 0, i = 1,2, assume that there is a semi-order restriction between ratios of means and standard deviations and sample numbers of two normal populations are different. A procedure of obtaining the maximum likelihood estimators of μi’s and σi’s under the semi-order restrictions is proposed. For i = 3 case, some connected results and simulations are given.展开更多
文摘Suppose that the time series Xt satisfieswhere α0≥δ>0,αi≥0 for i=1,2,…,q;βi,i=1,…,p, are real numbers; p and q are the order of the model. The sequence {ξt};(0,1) and is independent of {hs,s≤t} for fixed t. The above model is usually written as AR(p)-ARCH(q).We consider stationary series AR(p)-ARCH(q) model and assume the stationary field is θ0. We express this statement asH1:α1≥α2…≥αq,β1≥β2≥…≥βp and we consider an order restricted testing problem, which is to testH0:α1=α2=…=αq,β1=β2=…=βpagainst H1-H0. We derive the likelihood ratio (LR) test statistic and its asymptotic distri-
文摘In this paper, we study a stationary AR(p)-ARCH(q) model with parameter vectors α and β. We propose a method for computing the maximum likelihood estimator (MLE) of parameters under the nonnegative restriction. A similar method is also proposed for the case that the parameters are restricted by a simple order: α1≥α2≥…≥αq and β1≥β2≥…≥βp. The strong consistency of the above two estimators is discussed. Furthermore, we consider the problem of testing homogeneity of parameters against the simple order restriction. We give the likelihood ratio (LR) test statistic for the testing problem and derive its asymptotic null distribution.
文摘In this paper,a statistical prediction problem under ordered location and scale parameters are considered.Double-shrinkage predictors are given which use all the available data and improve on single-shrinkage predictors,and hence the best equivariant predictors.
基金supported by the financing program AAAA-A16-116021010082-8。
文摘A biased sampling algorithm for the restricted Boltzmann machine(RBM) is proposed, which allows generating configurations with a conserved quantity. To validate the method, a study of the short-range order in binary alloys with positive and negative exchange interactions is carried out. The network is trained on the data collected by Monte–Carlo simulations for a simple Ising-like binary alloy model and used to calculate the Warren–Cowley short-range order parameter and other thermodynamic properties. We demonstrate that the proposed method allows us not only to correctly reproduce the order parameters for the alloy concentration at which the network was trained, but can also predict them for any other concentrations.
基金supported by the National Natural Science Foundation of China(Nos.12174208 and 32227802)National Key Research and Development Program of China(No.2022YFC3400600)+2 种基金Guangdong Major Project of Basic and Applied Basic Research(No.2020B0301030009)Fundamental Research Funds for the Central Universities(Nos.2122021337 and 2122021405)the 111 Project(No.B23045).
文摘Collective cell migration is a coordinated movement of multi-cell systems essential for various processes throughout life.The collective motions often occur under spatial restrictions,hallmarked by the collective rotation of epithelial cells confined in circular substrates.Here,we aim to explore how geometric shapes of confinement regulate this collective cell movement.We develop quantitative methods for cell velocity orientation analysis,and find that boundary cells exhibit stronger tangential ordering migration than inner cells in circular pattern.Furthermore,decreased tangential ordering movement capability of collective cells in triangular and square patterns are observed,due to the disturbance of cell motion at unsmooth corners of these patterns.On the other hand,the collective cell rotation is slightly affected by a convex defect of the circular pattern,while almost hindered with a concave defect,also resulting from different smoothness features of their boundaries.Numerical simulations employing cell Potts model well reproduce and extend experimental observations.Together,our results highlight the importance of boundary smoothness in the regulation of collective cell tangential ordering migration.
文摘In recent years,the“power restriction”measures were taken in many localities,industrial electricity consumption was interrupted,mainly in the“two high”(high energy consumption and high pollutant emission)enterprises.Take the“power restriction”event in 2021 as an example,this event affected a wide range of regions and disrupted people’s livelihood.It not only refers to the power switch and rationing measures taken by individual regions,but also includes differentiated policies implemented by over 20 provinces to limit power supply and industrial production.This paper investigated in detail and summarized the different requirements of power restriction across the country,through the comparison of annual growth rates of power generation and industrial added value,the comparison results of energy intensity,electricity production,power consumption and the industrial growth rate in each province are analyzed.Industrial enterprises and related industrial chains were most heavily affected by the“power restriction”event,mainly in steel,cement,electrolytic aluminum,industrial silicon,textile printing and dyeing,chemical fiber,chemical and other enterprises with high energy consumption and high pollutants emission.The measures to limit electricity will affect the normal production of enterprises to a certain extent,leading to not only the decrease of production efficiency,but also the increase of energy consumption and pollutant emission per unit product.Energy management measures such as differentiated electricity price have limited effect on the output of“two high”industrial products,and the economic leverage of differentiated electricity price is gradually being diluted by the price rise of end products.This paper analyzed the reasons and explored several key problems that need special attention.then recommended certain countermeasures for its appropriate application in the future.
文摘The parameters of probability distributions under partial order restrictions are usually estimated by maximum likelihood estimates(MLE) and formulated as a maximization problem with a multimodal objective function subject to partial order restrictions. In order to obtain the global optimal estimation of parameters, this paper presents a genetic algorithm and illustrates its effectiveness by some numerical examples.
基金the National Natural Science Foundation of China (No.10431010)the Science Foundation of the Educational Department of Liaoning Province (No. 20060409)
文摘For two normal populations with unknown means μi and variances σi2 > 0, i = 1,2, assume that there is a semi-order restriction between ratios of means and standard deviations and sample numbers of two normal populations are different. A procedure of obtaining the maximum likelihood estimators of μi’s and σi’s under the semi-order restrictions is proposed. For i = 3 case, some connected results and simulations are given.