In this study, the statistical powers of Kolmogorov-Smimov two-sample (KS-2) and Wald Wolfowitz (WW) tests, non-parametric tests used in testing data from two independent samples, have been compared in terms of fi...In this study, the statistical powers of Kolmogorov-Smimov two-sample (KS-2) and Wald Wolfowitz (WW) tests, non-parametric tests used in testing data from two independent samples, have been compared in terms of fixed skewness and fixed kurtosis by means of Monte Carlo simulation. This comparison has been made when the ratio of variance is two as well as with equal and different sample sizes for large sample volumes. The sample used in the study is: (25, 25), (25, 50), (25, 75), (25, 100), (50, 25), (50, 50), (50, 75), (50, 100), (75, 25), (75, 50), (75, 75), (75, 100), (100, 25), (100, 50), (100, 75), and (100, 100). According to the results of the study, it has been observed that the statistical power of both tests decreases when the coefficient of kurtosis is held fixed and the coefficient of skewness is reduced while it increases when the coefficient of skewness is held fixed and the coefficient of kurtosis is reduced. When the ratio of skewness is reduced in the case of fixed kurtosis, the WW test is stronger in sample volumes (25, 25), (25, 50), (25, 75), (25, 100), (50, 75), and (50, 100) while KS-2 test is stronger in other sample volumes. When the ratio of kurtosis is reduced in the case of fixed skewness, the statistical power of WW test is stronger in volume samples (25, 25), (25, 75), (25, 100), and (75, 25) while KS-2 test is stronger in other sample volumes.展开更多
In the paper,we study the strong uniform consistency for the kernal estimates of random window w■th of density function and its derivatives under the condition that the sequence{X_n}of the ■ are the identically Φ-m...In the paper,we study the strong uniform consistency for the kernal estimates of random window w■th of density function and its derivatives under the condition that the sequence{X_n}of the ■ are the identically Φ-mixing random variabks.展开更多
In statistical theory, a statistic that is function of sample observations is used to estimate distribution parameter. This statistic is called unbiased estimate if its expectation is equal to theoretical parameter. P...In statistical theory, a statistic that is function of sample observations is used to estimate distribution parameter. This statistic is called unbiased estimate if its expectation is equal to theoretical parameter. Proving whether or not a statistic is unbiased estimate is very important but this proof may require a lot of efforts when statistic is complicated function. Therefore, this research facilitates this proof by proposing a theorem which states that the expectation of variable x 〉 0 is u if and only if the limit of logarithm expectation of x approaches logarithm of u. In order to make clear of this theorem, the research gives an example of proving correlation coefficient as unbiased estimate by taking advantages of this theorem.展开更多
The procedure of stratified double quartile ranked set sampling (SDQRSS) method is introduced to estimate the population mean. The SDQRSS is compared with the simple random sampling (SRS), stratified ranked set sa...The procedure of stratified double quartile ranked set sampling (SDQRSS) method is introduced to estimate the population mean. The SDQRSS is compared with the simple random sampling (SRS), stratified ranked set sampling (SRSS) and stratified simple random sampling (SSRS). It is shown that SDQRSS estimator is an unbiased of the population mean and more efficient than SRS, SRSS and SSRS for symmetric and asymmetric distributions. In addition, by SDQRSS we can increase the efficiency of mean estimator for specific value of the sample size.展开更多
The tax differences is the enterprise according to the provisions of accounting standards to calculate the total profit and tax calculated according to the enterprise income tax's tax base taxable income differences....The tax differences is the enterprise according to the provisions of accounting standards to calculate the total profit and tax calculated according to the enterprise income tax's tax base taxable income differences. Enterprise accounting standards and tax for the same subject for different purposes, leading to both the principle is different, as well as for the same matter measurement and confirmation of different, resulting in tax differences. In this paper, from the aspect of theory to the study of tax differences, from tax differences that the tax law and accounting purposes different proceed with, on the basis of theoretical analysis, design a regression model from empirical research on tax differences. According to the 2009,2010 and201 lthree annual sample data regression results, discussed in the new" accounting standards for business enterprises" of corporate tax difference change tendency, and according to the tax law and accounting standards caused by the different effects of tax differences for the main project correlation analysis, so as to verify the theoretical expectations.展开更多
Consider the following heteroscedastic semiparametric regression model:where {Xi, 1 〈 i 〈 n} are random design points, errors {ei, 1 〈 i 〈 n} are negatively associated (NA) random variables, (r2 = h(ui), and...Consider the following heteroscedastic semiparametric regression model:where {Xi, 1 〈 i 〈 n} are random design points, errors {ei, 1 〈 i 〈 n} are negatively associated (NA) random variables, (r2 = h(ui), and {ui} and {ti} are two nonrandom sequences on [0, 1]. Some wavelet estimators of the parametric component β, the non- parametric component g(t) and the variance function h(u) are given. Under some general conditions, the strong convergence rate of these wavelet estimators is O(n- 1 log n). Hence our results are extensions of those re, sults on independent random error settings.展开更多
We are concerned with robust estimation procedures to estimate the parameters in partially linear models with large-dimensional covariates. To enhance the interpretability, we suggest implementing a noncon- cave regul...We are concerned with robust estimation procedures to estimate the parameters in partially linear models with large-dimensional covariates. To enhance the interpretability, we suggest implementing a noncon- cave regularization method in the robust estimation procedure to select important covariates from the linear component. We establish the consistency for both the linear and the nonlinear components when the covariate dimension diverges at the rate of o(√n), where n is the sample size. We show that the robust estimate of linear component performs asymptotically as well as its oracle counterpart which assumes the baseline function and the unimportant covariates were known a priori. With a consistent estimator of the linear component, we estimate the nonparametric component by a robust local linear regression. It is proved that the robust estimate of nonlinear component performs asymptotically as well as if the linear component were known in advance. Comprehensive simulation studies are carried out and an application is presented to examine the finite-sample performance of the proposed procedures.展开更多
This paper proposes an interval method to explore the relationship between the exchange rate of Australian dollar against US dollar and the gold price, using weekly, monthly and quarterly data. With the interval metho...This paper proposes an interval method to explore the relationship between the exchange rate of Australian dollar against US dollar and the gold price, using weekly, monthly and quarterly data. With the interval method, interval sample data are formed to present the volatility of variables. The ILS approach is extended to multi-model estimation and the computational schemes are provided. The empirical evidence suggests that the ILS estimates well characterize how the exchange rate relates to the gold price, both in the long-run and short-run. The comparison between the interval and point methods indicates that the difference between the OLS and the ILS estimates is increasing from weekly data to quarterly data, since the lowest frequency point data lost the most information of volatility.展开更多
Abstract In this paper, we investigate the effective condition numbers for the generalized Sylvester equation (AX - YB, DX - YE) = (C,F), where A,D ∈ Rm×m B,E ∈ Rn×n and C,F ∈ Rm×n. We apply the ...Abstract In this paper, we investigate the effective condition numbers for the generalized Sylvester equation (AX - YB, DX - YE) = (C,F), where A,D ∈ Rm×m B,E ∈ Rn×n and C,F ∈ Rm×n. We apply the small sample statistical method for the fast condition estimation of the generalized Sylvester equation, which requires (9(m2n + mn2) flops, comparing with (-O(m3 + n3) flops for the generalized Schur and generalized Hessenberg- Schur methods for solving the generalized Sylvester equation. Numerical examples illustrate the sharpness of our perturbation bounds.展开更多
This paper develops the large sample properties of the solutions of the general estimating equations which are unbiased or asymptotically unbiased or with nuisance parameters for correlated data.The authors do not mak...This paper develops the large sample properties of the solutions of the general estimating equations which are unbiased or asymptotically unbiased or with nuisance parameters for correlated data.The authors do not make the assumption that the estimating equations come from some objective function when we establish the large sample properties of the solutions.So these results extend the work of Newey and McFadden(1994) and are more widely applicable.Furthermore,we provide some examples to justify the importance of our work.展开更多
Two revised regional importance measures(RIMs),that is,revised contribution to variance of sample mean(RCVSM)and revised contribution to variance of sample variance(RCVSV),are defined herein by using the revised means...Two revised regional importance measures(RIMs),that is,revised contribution to variance of sample mean(RCVSM)and revised contribution to variance of sample variance(RCVSV),are defined herein by using the revised means of sample mean and sample variance,which vary with the reduced range of the epistemic parameter.The RCVSM and RCVSV can be computed by the same set of samples,thus no extra computational cost is introduced with respect to the computations of CVSM and CVSV.From the plots of RCVSM and RCVSV,accurate quantitative information on variance reductions of sample mean and sample variance can be read because of reduced upper bound of the range of the epistemic parameter.For general form of quadratic polynomial output,the analytical solutions of the original and the revised RIMs are given.Numerical example is employed and results demonstrate that the analytical results are consistent and accurate.An engineering example is applied to testify the validity and rationality of the revised RIMs,which can give instructions to the engineers about how to reduce variance of sample mean and sample variance by reducing the range of epistemic parameters.展开更多
This paper studies nonparametric estimation of the regression function with surrogate outcome data under double-sampling designs, where a proxy response is observed for the full sample and the true response is observe...This paper studies nonparametric estimation of the regression function with surrogate outcome data under double-sampling designs, where a proxy response is observed for the full sample and the true response is observed on a validation set. A new estimation approach is proposed for estimating the regression function. The authors first estimate the regression function with a kernel smoother based on the validation subsample, and then improve the estimation by utilizing the information on the incomplete observations from the non-validation subsample and the surrogate of response from the full sample. Asymptotic normality of the proposed estimator is derived. The effectiveness of the proposed method is demonstrated via simulations.展开更多
This paper derives some uniform convergence rates for kernel regression of some index functions that may depend on infinite dimensional parameter. The rates of convergence are computed for independent, strongly mixing...This paper derives some uniform convergence rates for kernel regression of some index functions that may depend on infinite dimensional parameter. The rates of convergence are computed for independent, strongly mixing and weakly dependent data respectively. These results extend the existing literature and are useful for the derivation of large sample properties of the estimators in some semiparametric and nonparametric models.展开更多
文摘In this study, the statistical powers of Kolmogorov-Smimov two-sample (KS-2) and Wald Wolfowitz (WW) tests, non-parametric tests used in testing data from two independent samples, have been compared in terms of fixed skewness and fixed kurtosis by means of Monte Carlo simulation. This comparison has been made when the ratio of variance is two as well as with equal and different sample sizes for large sample volumes. The sample used in the study is: (25, 25), (25, 50), (25, 75), (25, 100), (50, 25), (50, 50), (50, 75), (50, 100), (75, 25), (75, 50), (75, 75), (75, 100), (100, 25), (100, 50), (100, 75), and (100, 100). According to the results of the study, it has been observed that the statistical power of both tests decreases when the coefficient of kurtosis is held fixed and the coefficient of skewness is reduced while it increases when the coefficient of skewness is held fixed and the coefficient of kurtosis is reduced. When the ratio of skewness is reduced in the case of fixed kurtosis, the WW test is stronger in sample volumes (25, 25), (25, 50), (25, 75), (25, 100), (50, 75), and (50, 100) while KS-2 test is stronger in other sample volumes. When the ratio of kurtosis is reduced in the case of fixed skewness, the statistical power of WW test is stronger in volume samples (25, 25), (25, 75), (25, 100), and (75, 25) while KS-2 test is stronger in other sample volumes.
基金supported by Natural Science Foun■ion of Henan P■visial Commission of Bdusation
文摘In the paper,we study the strong uniform consistency for the kernal estimates of random window w■th of density function and its derivatives under the condition that the sequence{X_n}of the ■ are the identically Φ-mixing random variabks.
文摘In statistical theory, a statistic that is function of sample observations is used to estimate distribution parameter. This statistic is called unbiased estimate if its expectation is equal to theoretical parameter. Proving whether or not a statistic is unbiased estimate is very important but this proof may require a lot of efforts when statistic is complicated function. Therefore, this research facilitates this proof by proposing a theorem which states that the expectation of variable x 〉 0 is u if and only if the limit of logarithm expectation of x approaches logarithm of u. In order to make clear of this theorem, the research gives an example of proving correlation coefficient as unbiased estimate by taking advantages of this theorem.
文摘The procedure of stratified double quartile ranked set sampling (SDQRSS) method is introduced to estimate the population mean. The SDQRSS is compared with the simple random sampling (SRS), stratified ranked set sampling (SRSS) and stratified simple random sampling (SSRS). It is shown that SDQRSS estimator is an unbiased of the population mean and more efficient than SRS, SRSS and SSRS for symmetric and asymmetric distributions. In addition, by SDQRSS we can increase the efficiency of mean estimator for specific value of the sample size.
文摘The tax differences is the enterprise according to the provisions of accounting standards to calculate the total profit and tax calculated according to the enterprise income tax's tax base taxable income differences. Enterprise accounting standards and tax for the same subject for different purposes, leading to both the principle is different, as well as for the same matter measurement and confirmation of different, resulting in tax differences. In this paper, from the aspect of theory to the study of tax differences, from tax differences that the tax law and accounting purposes different proceed with, on the basis of theoretical analysis, design a regression model from empirical research on tax differences. According to the 2009,2010 and201 lthree annual sample data regression results, discussed in the new" accounting standards for business enterprises" of corporate tax difference change tendency, and according to the tax law and accounting standards caused by the different effects of tax differences for the main project correlation analysis, so as to verify the theoretical expectations.
基金supported by the National Natural Science Foundation of China (No. 11071022)the Key Project of the Ministry of Education of China (No. 209078)the Youth Project of Hubei Provincial Department of Education of China (No. Q20122202)
文摘Consider the following heteroscedastic semiparametric regression model:where {Xi, 1 〈 i 〈 n} are random design points, errors {ei, 1 〈 i 〈 n} are negatively associated (NA) random variables, (r2 = h(ui), and {ui} and {ti} are two nonrandom sequences on [0, 1]. Some wavelet estimators of the parametric component β, the non- parametric component g(t) and the variance function h(u) are given. Under some general conditions, the strong convergence rate of these wavelet estimators is O(n- 1 log n). Hence our results are extensions of those re, sults on independent random error settings.
基金supported by National Institute on Drug Abuse(Grant Nos.R21-DA024260 and P50-DA10075)National Natural Science Foundation of China(Grant Nos.11071077,11371236,11028103,11071022 and 11028103)+2 种基金Innovation Program of Shanghai Municipal Education CommissionPujiang Project of Science and Technology Commission of Shanghai Municipality(Grant No.12PJ1403200)Program for New Century Excellent Talents,Ministry of Education of China(Grant No.NCET-12-0901)
文摘We are concerned with robust estimation procedures to estimate the parameters in partially linear models with large-dimensional covariates. To enhance the interpretability, we suggest implementing a noncon- cave regularization method in the robust estimation procedure to select important covariates from the linear component. We establish the consistency for both the linear and the nonlinear components when the covariate dimension diverges at the rate of o(√n), where n is the sample size. We show that the robust estimate of linear component performs asymptotically as well as its oracle counterpart which assumes the baseline function and the unimportant covariates were known a priori. With a consistent estimator of the linear component, we estimate the nonparametric component by a robust local linear regression. It is proved that the robust estimate of nonlinear component performs asymptotically as well as if the linear component were known in advance. Comprehensive simulation studies are carried out and an application is presented to examine the finite-sample performance of the proposed procedures.
基金supported by the National Natural Science Foundation of China,Research Granting Committee of Hong Kong and Chinese Academy of Sciences
文摘This paper proposes an interval method to explore the relationship between the exchange rate of Australian dollar against US dollar and the gold price, using weekly, monthly and quarterly data. With the interval method, interval sample data are formed to present the volatility of variables. The ILS approach is extended to multi-model estimation and the computational schemes are provided. The empirical evidence suggests that the ILS estimates well characterize how the exchange rate relates to the gold price, both in the long-run and short-run. The comparison between the interval and point methods indicates that the difference between the OLS and the ILS estimates is increasing from weekly data to quarterly data, since the lowest frequency point data lost the most information of volatility.
基金supported by National Natural Science Foundation of China(Grant Nos.11001045,10926107 and 11271084)Specialized Research Fund for the Doctoral Program of Higher Education of MOE(Grant No. 20090043120008)+4 种基金Training Fund of NENU’S Scientific Innovation Project of Northeast Normal University(Grant No. NENU-STC08009)Program for Changjiang Scholars and Innovative Research Team in Universitythe Programme for Cultivating Innovative Students in Key Disciplines of Fudan University(973 Program Project)(Grant No. 2010CB327900)Doctoral Program of the Ministry of Education(Grant No.20090071110003)Shanghai Science & Technology Committee and Shanghai Education Committee(Dawn Project)
文摘Abstract In this paper, we investigate the effective condition numbers for the generalized Sylvester equation (AX - YB, DX - YE) = (C,F), where A,D ∈ Rm×m B,E ∈ Rn×n and C,F ∈ Rm×n. We apply the small sample statistical method for the fast condition estimation of the generalized Sylvester equation, which requires (9(m2n + mn2) flops, comparing with (-O(m3 + n3) flops for the generalized Schur and generalized Hessenberg- Schur methods for solving the generalized Sylvester equation. Numerical examples illustrate the sharpness of our perturbation bounds.
基金supported by NSFC 11171065NSFJS BK2011058+3 种基金China Postdoctoral Science Foundation funded project under Grant No.2010471366Jiangsu Planned Projects for Postdoctoral Research Funds under Grant No.1001068CNUST Research Funding under Grant No.2010ZYTS071National Social Science Foundation of China under Grant No.09BTJ004
文摘This paper develops the large sample properties of the solutions of the general estimating equations which are unbiased or asymptotically unbiased or with nuisance parameters for correlated data.The authors do not make the assumption that the estimating equations come from some objective function when we establish the large sample properties of the solutions.So these results extend the work of Newey and McFadden(1994) and are more widely applicable.Furthermore,we provide some examples to justify the importance of our work.
基金supported by the National Natural Science Foundation of China(Grant No.51175425)the Special Research Fund for the Doctoral Program of Higher Education of China(Grant No.20116102110003)
文摘Two revised regional importance measures(RIMs),that is,revised contribution to variance of sample mean(RCVSM)and revised contribution to variance of sample variance(RCVSV),are defined herein by using the revised means of sample mean and sample variance,which vary with the reduced range of the epistemic parameter.The RCVSM and RCVSV can be computed by the same set of samples,thus no extra computational cost is introduced with respect to the computations of CVSM and CVSV.From the plots of RCVSM and RCVSV,accurate quantitative information on variance reductions of sample mean and sample variance can be read because of reduced upper bound of the range of the epistemic parameter.For general form of quadratic polynomial output,the analytical solutions of the original and the revised RIMs are given.Numerical example is employed and results demonstrate that the analytical results are consistent and accurate.An engineering example is applied to testify the validity and rationality of the revised RIMs,which can give instructions to the engineers about how to reduce variance of sample mean and sample variance by reducing the range of epistemic parameters.
基金This research is supported by the National Natural Science Foundation of the US under Grant No. DMS- 0906482.
文摘This paper studies nonparametric estimation of the regression function with surrogate outcome data under double-sampling designs, where a proxy response is observed for the full sample and the true response is observed on a validation set. A new estimation approach is proposed for estimating the regression function. The authors first estimate the regression function with a kernel smoother based on the validation subsample, and then improve the estimation by utilizing the information on the incomplete observations from the non-validation subsample and the surrogate of response from the full sample. Asymptotic normality of the proposed estimator is derived. The effectiveness of the proposed method is demonstrated via simulations.
基金National Natural Science Foundation of China (Grant No. 70971082)Shanghai Leading Academic Discipline Project at Shanghai University of Finance and Economics (SHUFE) (Grant No. B803)Key Laboratory of Mathematical Economics (SHUFE), Ministry of Education
文摘This paper derives some uniform convergence rates for kernel regression of some index functions that may depend on infinite dimensional parameter. The rates of convergence are computed for independent, strongly mixing and weakly dependent data respectively. These results extend the existing literature and are useful for the derivation of large sample properties of the estimators in some semiparametric and nonparametric models.