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对《国防订单库存影响估计的一致性评论》的回应AI 解读

Gramlich and Galper (hereafter referred to as GG) indeed have performed a useful service by pointing out that an erroneous equation was included in my paper [3]. The corrected inventory change equation, the equation with all lagged orders included, was almost identical with the results obtained by applying GG's method (ii) to the order-inventory stock equation presented in Column (2), Table IV of my paper [3, p. 161]. The results are consistent when GG's methods (ii) and…

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扰动较小时 k 类估计量的比较AI 解读

A new approach to the choice of econometric estimators, called small-sigma asymptotics, is introduced and applied to the choice of k-class estimators of the parameters of a single equation in a system of linear simultaneous stochastic equations. I find that when the degree of overidentification is no more than six, the two stage least squares estimator uniformly dominates the limited information maximum likelihood estimator in a certain sense. The small sigma method can be…

参数线性但内生变量非线性的计量系统与两阶段最小二乘AI 解读

It is demonstrated that a variant of the two-stage least squares technique can be used to estimate the parameters of a nonlinear model. To do this, the reduced form equations of such models are derived and discussed; then certain problems particular to the estimation of nonlinear models are considered.

In two stage least squares estimation, when the matrix Z of predetermined variables has less than full column rank, Z'Z is singular. It is shown that in this situation 2SLS still can be used and that Y-the result of the first stage-is still uniquely determined; also shown is that 2SLS will often be equivalent to OLS. IN A LARGE SYSTEM containing many equations and many predetermined variables, it is a common occurrence to find that the second moment matrix involving all of…

This paper develops approximations of the Gram-Charlier type to the cumulative distribution function of the instrumental variables estimator on classical assumptions. In the special case where there are only two endogenous variables in the estimated equation, exact values of the cumulative distribution function are computed by numerical integration and compared with the approximations. Although the error in the approximation depends critically on the parameters of the…

联立方程最小绝对值与最小二乘估计量的小样本性质比较AI 解读

In this paper a distribution sampling study consisting of four major experiments is described. The L1 norm is employed in two new estimating techniques, direct least absolute (DLA) and two-stage least absolute (TSLA), and these two are compared to direct least squares (DLS) and two-stage least squares (TSLS). Four experiments testing the normal distribution case, a multicollinearity problem, a heteroskedastic variance problem, and a misspecified model were conducted. Two…

摘要暂缺

In this paper various methods for the estimation of simultaneous equation models with lagged endogenous variables and first order serially correlated errors are discussed. The methods differ in the number of instrumental variables used. The asymptotic and small sample properties of the various methods are compared, and the variables which must be included as instruments to insure consistent estimates are derived. A suggestion on how to estimate the approximate covariance…

This paper reports on a study of the timing of the economic impact of government defense procurement. By assuming that the letting of new orders signals the beginning and shipments signal the end of the impact of defense procurement, this research investigates the effects of changes in product mix and capacity utilization on the duration of such impacts. The effects of changes in product mix and capacity utilization on inventory accumulation are also investigated. RECENT…

普通最小二乘与两阶段最小二乘估计量的精确抽样分布AI 解读

This paper presents the exact sampling distributions of the ordinary and the two-stage least squares estimators of a structural parameter in a structural equation with two endogenous variables in a complete system of stochastic equations. The results show that the distributions of the two estimators are essentially similar to each other. It can also be seen that both distributions depend crucially upon the deviation of a regression coefficient of disturbance terms of two…

普通最小二乘与两阶段最小二乘估计量的精确抽样分布AI 解读

This paper presents the exact sampling distributions of the ordinary and the two-stage least squares estimators of a structural parameter in a structural equation with two endogenous variables in a complete system of stochastic equations. The results show that the distributions of the two estimators are essentially similar to each other. It can also be seen that both distributions depend crucially upon the deviation of a regression coefficient of disturbance terms of two…

多元统计中的缺失观测之四：简单线性回归札记AI 解读

In this note we examine the bias and small sample efficiency of certain estimators for the parameters of a linear regression function when some observations are missing. The estimators studies in this paper were suggested by the large sample study reported in this issue of the Journal. We conclude that our asymptotically unbiased estimators of β and μy | x have negligible bias in sample sizes as small as n = 20, and that our asymptotically unbiased estimator of σ2 may have…

摘要暂缺

This paper presents the region of coverage of the curve shape characteristics, α23 and δ = (2α4 −3α23 −6) /(α4+3), for a certain general system of distributions, Burr (1942). These curve-shape characteristics were chosen for comparison with the Pearson system because of the simplicity with which they map the members of the latter system, Craig (1936). It is here shown that the present system covers almost all of the regions of the main Pearson Types IV and VI, and an…

近似设定与 k 类估计量的选择AI 解读

This paper carries on work in [2] and [4] on the asymptotic effects of small specification error in simultaneous equation estimation. The specification errors considered are inherent in the approximate nature of econometric models. It is shown that for any parameter and small enough specification error, the probability limits of two-stage least squares and limited-information maximum-likelihood, while different, lie on the same side of the true parameter value, the…

联立方程估计量对模型随机假设的敏感性AI 解读

The paper reports the results of several sampling experiments investigating the sensitivity of various simultaneous-equations estimators to errors in the exogenous variables, stochastic coefficients, heteroskedastic disturbances and auto correlated disturbances. The estimates studied are direct least squares, two-stage least squares, Nagar's unbiased k-class estimator, limited-information maximum likelihood, three-stage least squares, and full-information maximum likelihood.…

联立方程估计量对模型随机假设的敏感性AI 解读

The paper reports the results of several sampling experiments investigating the sensitivity of various simultaneous-equations estimators to errors in the exogenous variables, stochastic coefficients, heteroskedastic disturbances and auto correlated disturbances. The estimates studied are direct least squares, two-stage least squares, Nagar's unbiased k-class estimator, limited-information maximum likelihood, three-stage least squares, and full-information maximum likelihood.…

条件期望的一个极值性质AI 解读

This note demonstrates that for bivariate random variables (X, Y) the correlation between Y and functions of X is maximized by the function f(X) = E(Y | X). The result provides a finite sample justification for the common scoring prooedure of giving the jth largest observation the score of the expected value of the jth order statistic of a standard distribution. Asymptotically the result also indicates that when one is using instrumental variables as an aid to estimation,…

经济时间序列的季节调整与多元回归分析AI 解读

The logical implications of certain simple consistency requirements for appraising alternative procedures for seasonal adjustment constitute the first problem considered in this paper. It is shown that any sum preserving technique of seasonal adjustment that satisfies the quite reasonable requirements of orthogonality and idempotency can be executed on the electronic computer by standard least squares regression procedures. Problems involved in utilizing seasonally adjusted…

变量测量误差与恩格尔曲线分析AI 解读

The traditional method of estimating Engel curve parameters uses either (recorded) income or total expenditure as an independent variable in least squares analysis. Neither of these is, however, a satisfactory index of the economic position of the family. This results in biased estimates of the income elasticities of the various consumption categories. The bias can, however, be eliminated in large samples by using both income and total expenditures in the estimation…

不同联立方程估计量的蒙特卡洛研究AI 解读

We study the small sample properties of the simultaneous equation estimators by a Monte Carlo approach. The four methods of estimation considered are: least squares, two-stage least squares, unbiased and minimumsecond-moment. The last of these four methods possesses the smallest secondorder sampling moments about the true parameter value in a majority of cases, while two-stage least squares shows the smallest bias in all cases. It is also founld that the usual asymptotic…

用工具变量估计残差自相关的关系AI 解读

SUMMARY The instrumental variables method of estimating the coefficients of a linear relationship between time series which have measurement errors is applied to the case where the coefficients are functions of a set of parameters. The asymptotic error variance matrix of the estimates is obtained, asymptotic tests for the existence and identification of the suggested form of relationship are suggested, and asymptotic confidence regions are given. The general theory is then…

使用工具变量估计经济关系AI 解读

which the relationships are not exact, so that a set of ideal economic variables is assumed to be generated by a set of dynamic stochastic relationships, as in Koopmans [12], and the actual economic time series are assumed to differ from the ideal economic variables because of random disturbances or measurement errors. The asymptotic error variance matrix for the coefficients of one of the relationships is obtained in the case in which these relationships are estimated using…