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利用最大似然预测纪录AI 解读

A maximum likelihood method of fitting a model to a series of records is proposed, using ideas from the analysis of censored data to construct a likelihood function based on observed records. This method is tried out by fitting several models to series of athletics records for mile and marathon races. A form of residual analysis is proposed for testing the models. Forecasting consequences are also considered. In the case of mile records, a steady linear improvement since…

ARMA 估计的回归程序AI 解读

Regression procedures for parameter estimation in autoregression moving average (ARMA) models are discussed, mainly for providing initial estimates for iterative maximization of a Gaussian likelihood. An iterative procedure of Spliid (1983) is compared to a procedure of Hannan and Rissanen (1982), and a global convergence result is established for an iterative modification of Spliid's procedure. Spliid's iteration does not always converge; when it does, it has the same…

用最大似然法预测纪录AI 解读

A maximum likelihood method of fitting a model to a series of records is proposed, using ideas from the analysis of censored data to construct a likelihood function based on observed records. This method is tried out by fitting several models to series of athletics records for mile and marathon races. A form of residual analysis is proposed for testing the models. Forecasting consequences are also considered. In the case of mile records, a steady linear improvement since…

对美国商务部领先指标方法的检验AI 解读

Bivariate time series models are built that describe the empirical relationships between industrial production and components of the Composite Index of Leading Indicators (CLI). This reveals the indicators' average lead times at all points of the business cycle, the forms of the distributed lags involved, and their ability to explain later movements in economic activity. The relationship between industrial production and the CLI is also examined and used to test the…

时间序列解聚与预测：贝叶斯分析AI 解读

The problem of temporal disaggregation of time series is analyzed by means of Bayesian methods. The disaggregated values are obtained through a posterior distribution derived by using a diffuse prior on the parameters. Further analysis is carried out assuming alternative conjugate priors. The means of the different posterior distributions are shown to be equivalent to some sampling theory results. Bayesian prediction intervals are obtained. Forecasts for future disaggregated…

异频存量与流量数据下连续时间 ARMAX 模型的高斯似然AI 解读

For purposes of maximum likelihood estimation, we show how to compute the Gaussian likelihood function when the data are generated by a higher-order continuous-time vector ARMAX model and are observed as stocks and flows at different frequencies. Continuous-time ARMAX models are analogous to discrete-time autoregressive moving-average models with distributed-lag exogenous variables. Stocks are variables observed at points in time and flows are variables observed as integrals…

存在结构变化时单个结构方程的估计AI 解读

Estimation of a single structural equation when there exists structural change is considered. Equality of structural variances in different samples is shown to affect the identification condition and asymptotic efficiency of best asymptotically normal estimators when the reduced-form covariance matrices differ by the structural change. The limited information maximum likelihood estimator is presented with its asymptotic property and compared with an alternative estimator.

估计向量自回归过程的移动平均系数的渐近分布AI 解读

The coefficients of the moving average (MA) representation of a vector autoregressive (VAR) process are the dynamic multipliers of the system. These quantities are often used to analyze the relationships between the variables involved. Assuming that the actual data generation process is stationary and has a VAR representation of unknown and possibly infinite order, the asymptotic distribution of the MA coefficients is derived. A computationally simple formula for the…

评论：Bierens 方法与时间序列模型设定检验AI 解读

Professor Bierens' approach is definitely original and interesting. We think it might become important, in particular, for testing correct specification of models (even nonlinear) in the time series context. For example, his test in Section 6 is (to our knowledge) the first test of correct specification of a model which is consistent against all stationary alternatives. Usually, specification tests checking the structure of dependence are only designed to test against a…

经济时间序列的 ARMA 记忆指标建模AI 解读

In this paper, it will be shown that if we condition a k -variate rational-valued time series process on its entire past, it is possible to capture all relevant information on the past of the process by a single random variable. This scalar random variable can be formed as an autoregressive moving average of past observations; Since economic data are usually reported in a finite number of digits, this result applies to virtually all economic time series. Therefore, economic…

时间序列分析的最优秩方法：检验 ARMA 模型AI 解读

The problem of testing a given ARMA model (in which the density of the generating white noise is unspecified) against other ARMA models is considered. A distribution-free asymptotically most powerful test, based on a generalized linear serial rank statistic, is provided against contiguous ARMA alternatives with specified coefficients. In the case when the ARMA model in the alternative has unspecified coefficients, the asymptotic sufficiency (in the sense of Le Cam) of a…

不稳定自回归过程最小二乘估计的极限分布AI 解读

An autoregressive process $y_n = \beta_1y_{n-1} + \cdots + \beta_py_{n-p} + \varepsilon_n$ is said to be unstable if the characteristic polynomial $\phi(z) = 1 - \beta_1z - \cdots - \beta_pz^p$ has all roots on or outside the unit circle. The limiting distribution of the least squares estimate of $(\beta_1, \cdots, \beta_p)$ is derived and characterized as a functional of stochastic integrals under a $2 + \delta$ moment assumption on $\varepsilon_n$. Up to the present,…

检测分布变化的动态抽样方法AI 解读

The problem of detecting a change in drift of Brownian motion is considered in the Bayesian framework with the time of change having a (prior) exponential distribution. To the well known problem of finding an optimal stopping rule for "declaring a change," we add the option of continuously controlling the sampling rates--resulting in controlling the variance coefficient of the process. The combined problem of finding an optimal rate function (dynamic sampling) together with…

回归系数恒定性对随机游走备择检验的渐近理论AI 解读

The LBI (locally best invariant) test is suggested under normality for the constancy of regression coefficients against the alternative hypothesis that one component of the coefficients follows a random walk process. We discuss the limiting null behavior of the test statistic without assuming normality under two situations, where the initial value of the random walk process is known or unknown. The limiting distribution is that of a quadratic functional of Brownian motion…

变点问题中秩检验的 Bahadur 效率AI 解读

A sequence of independent random variables $X_1, X_2, \cdots, X_N$ is said to have a change point if $X_1, X_2, \cdots, X_n$ have a common distribution $F$ and $X_{n+1}, \cdots, X_N$ have a common distribution $G, G \neq F$. Consider the problem of testing the null hypothesis of no change against the alternative of a change $G < F$ at an unknown change point $n$. Two classes of statistics based upon two-sample linear rank statistics (max- and sum-type) are compared in terms…

非参数变点估计AI 解读

Consider a sequence of independent random variables $\{X_i: 1 \leq i \leq n\}$ having cdf $F$ for $i \leq \theta n$ and cdf $G$ otherwise. A class of strongly consistent estimators for the change-point $\theta \in (0, 1)$ is proposed. The estimators require no knowledge of the functional forms or parametric families of $F$ and $G$. Furthermore, $F$ and $G$ need not differ in their means (or other measure of location). The only requirement is that $F$ and $G$ differ on a set…

经济时间序列季节性的动态理论研究AI 解读

Several economists, notably Plosser (1978), Sargent (1978), and Wallis (1978) refuted the assumption that the seasonal component of endogenous variables in a dynamic economic model has almost all of its power restricted to what is termed seasonal frequency and its harmonics. In this article, a model with a closed-form solution is formulated to provide more insight into the arguments put forward by economists. It is concluded that univariate seasonal adjustment cannot be…

含单整回归变量时普通最小二乘与广义最小二乘的渐近等价性AI 解读

It is shown that in the multiple regression model y 1 = x 1′β + u t, where u t, is a stationary autoregressive process and x 1 is an integrated m-vector process, the asymptotic distributions of the ordinary least squares (OLS) and generalized least squares (GLS) estimators of β are identical. This generalizes a result obtained by Krämer (1986) for two-variate regression and extends fixed regressor theory developed by Grenander and Rosenblatt (1957). Our approach uses a…

经济时间序列季节性的动态理论探索AI 解读

Several economists, notably Plosser (1978), Sargent (1978), and Wallis (1978) refuted the assumption that the seasonal component of endogenous variables in a dynamic economic model has almost all of its power restricted to what is termed seasonal frequency and its harmonics. In this article, a model with a closed-form solution is formulated to provide more insight into the arguments put forward by economists. It is concluded that univariate seasonal adjustment cannot be…

非高斯平稳时间序列的时间可逆性与移动平均表示唯一性AI 解读

A recent result by Findley (1986) on the uniqueness of moving average representations for non-Gaussian time series is shown to establish a conjecture by Weiss (1975) on the time-reversibility of general linear processes.

大量小样本中的序列相关检验AI 解读

Methods are outlined for testing for serial correlation in large numbers of small samples, emphasis being placed on samples of size three. Some data on pulse rates are analysed in illustration.

总量劳动供给与需求波动的计量分析AI 解读

This paper contains an equilibrium model of the labor market. The supply function allows f or temporal substitution in response to wage fluctuations, and the de mand function allows for adjustment costs. Two related issues are emp hasized: identification of supply and demand functions, and sources o f serial correlation in employment and real wages. When the supply an d demand shocks are AR(1) processes, the equilibrium process for empl oyment and real wages is a restricted…

NEAR(2) 与 NLAR(2) 时间序列模型的一致估计AI 解读

SUMMARY Consistent and asymptotically normal estimates for all four parameters of the NEAR(2) and NLAR(2) time series models are obtained. The estimates are given in explicit form and are easy to compute, but with simulation experiments the standard errors are large, especially for small values of the parameters, so very substantial sample sizes may be needed. Hence, from this point of view, the NEAR(2) and NLAR(2) models are of limited practical value. The simulations…

评《时间序列回归中一种被忽视的供需分离方法》AI 解读

This article examines some difficulties associated with the Haynes–Stone model and attempts to clarify how the model can be justified as representing the hypothesis that “quantity is demand determined and price is supply determined.” It also argues that the applications of such a model as was done by Haynes and Stone might not have resolved the controversies related to the Phillips curve and the supply function of exports (or imports).