serial.test(vars)
serial.test()所属R语言包:vars
Test for serially correlated errors
测试序列相关的错误
译者:生物统计家园网 机器人LoveR
描述----------Description----------
This function computes the multivariate Portmanteau- and Breusch-Godfrey test for serially correlated errors.
此函数计算多元混成,和Breusch-戈弗雷的测试序列相关的错误。
用法----------Usage----------
serial.test(x, lags.pt = 16, lags.bg = 5, type = c("PT.asymptotic",
"PT.adjusted", "BG", "ES") )
参数----------Arguments----------
参数:x
Object of class "varest"; generated by VAR(), or an object of class "vec2var"; generated by vec2var().
类的对象varest所产生的VAR(),或对象类的vec2var所产生的vec2var()。
参数:lags.pt
An integer specifying the lags to be used for the Portmanteau statistic.
一个整数,指定要使用的的混成统计的滞后。
参数:lags.bg
An integer specifying the lags to be used for the Breusch-Godfrey statistic.
一个整数,指定的滞后用于Breusch戈弗雷统计。
参数:type
Character, the type of test. The default is an asymptotic Portmanteau test.
字符,测试的类型。默认值是一个渐进的混成测试。
Details
详细信息----------Details----------
The Portmanteau statistic for testing the absence of up to the order h serially correlated disturbances in a stable VAR(p) is defined as:
混成进行测试的情况下,最多的顺序统计h序列相关的扰动在一个稳定的VAR(对)被定义为:
where \hat{C}_i = \frac{1}{T}∑_{t = i + 1}^T \bold{\hat{u}}_t \bold{\hat{u}}_{t - i}'. The test statistic is approximately distributed as χ^2(K^2(h - p)). This test statistic is choosen by setting type = "PT.asymptotic". For smaller sample sizes and/or values of h that are not sufficiently large, a corrected test statistic is computed as:
\hat{C}_i = \frac{1}{T}∑_{t = i + 1}^T \bold{\hat{u}}_t \bold{\hat{u}}_{t - i}'。检验统计量大约是分布χ^2(K^2(h - p))。该检验统计量choosen通过设置type = "PT.asymptotic"。对于规模较小的样本量和/或值的h不够大,修正后的检验统计量的计算为:
This test statistic can be accessed, if type = "PT.adjusted" is set.<br>
该检验统计量可以访问,如果type = "PT.adjusted"设置。<BR>
The Breusch-Godfrey LM-statistic is based upon the following auxiliary regressions:
Breusch-戈弗雷LM-统计数字是根据下面的辅助回归:
The null hypothesis is: H_0: B_1 = … = B_h = 0 and correspondingly the alternative hypothesis is of the form H_1: \exists \; B_i \ne 0 for i = 1, 2, …, h. The test statistic is defined as:
零假设是:H_0: B_1 = … = B_h = 0“和相应的备择假设的形式H_1: \exists \; B_i \ne 0i = 1, 2, …, h。的检验统计量的定义为:
where \tilde{Σ}_R and \tilde{Σ}_e assign the residual covariance matrix of the restricted and unrestricted model, respectively. The test statistic LM_h is distributed as χ^2(hK^2). This test statistic is calculated if type = "BG" is used.<br>
\tilde{Σ}_R和\tilde{Σ}_e分配剩余的协方差矩阵的限制和不受限制的模型,分别。检验统计量LM_h分布χ^2(hK^2)。该检验统计量的计算方法type = "BG"。<BR>
Edgerton and Shukur (1999) proposed a small sample correction, which is defined as:
埃杰顿和Shukur(1999)提出了一个小的样品校正,它被定义为:
with R_r^2 = 1 - |\tilde{Σ}_e | / |\tilde{Σ}_R|, r = ((K^2m^2 - 4)/(K^2 + m^2 - 5))^{1/2}, q = 1/2 K m - 1 and N = T - K - m - 1/2(K - m + 1), whereby n is the number of regressors in the original system and m = Kh. The modified test statistic is distributed as F(hK^2, int(Nr - q)). This modified statistic will be returned, if type = "ES" is provided in the call to serial().
R_r^2 = 1 - |\tilde{Σ}_e | / |\tilde{Σ}_R|,r = ((K^2m^2 - 4)/(K^2 + m^2 - 5))^{1/2},q = 1/2 K m - 1和N = T - K - m - 1/2(K - m + 1),即n是在原有系统中的回归系数和m = Kh。修改后的检验统计量分布F(hK^2, int(Nr - q))。此修改后的统计信息将被退回,如果type = "ES"在调用serial()。
值----------Value----------
A list with class attribute "varcheck" holding the following elements:<br>
类属性varcheck持下列元素:参考列表
参数:resid
A matrix with the residuals of the VAR.
一个矩阵的残差的VAR。
参数:pt.mul
A list with objects of class attribute "htest" containing the multivariate Portmanteau-statistic (asymptotic and adjusted.
一个列表对象的类属性htest包含多元混成统计(渐近调整。
参数:LMh
An object with class attribute "htest" containing the Breusch-Godfrey LM-statistic.
一个对象类的属性htest包含Breusch-戈弗雷LM-统计。
参数:LMFh
An object with class attribute "htest" containing the Edgerton-Shukur F-statistic.
对象类属性htest包含的埃杰顿Shukur F-统计。
注意----------Note----------
This function was named serial in earlier versions of package vars; it is now deprecated. See vars-deprecated too.
此功能被命名为serial在早期版本的包vars;它现在已经过时。见vars-deprecated太。
(作者)----------Author(s)----------
Bernhard Pfaff
参考文献----------References----------
models, Australian Economic Papers, 17: 334-355.
system perspective, Econometric Reviews, 18: 43-386.
regression equations when the regressors include lagged dependent variables, Econometrica, 46: 1303-1313.
University Press, Princeton.
Analysis, Springer, New York.
参见----------See Also----------
VAR, vec2var, plot
VAR,vec2var,plot
实例----------Examples----------
data(Canada)
var.2c <- VAR(Canada, p = 2, type = "const")
serial.test(var.2c, lags.pt = 16, type = "PT.adjusted")
转载请注明:出自 生物统计家园网(http://www.biostatistic.net)。
注:
注1:为了方便大家学习,本文档为生物统计家园网机器人LoveR翻译而成,仅供个人R语言学习参考使用,生物统计家园保留版权。
注2:由于是机器人自动翻译,难免有不准确之处,使用时仔细对照中、英文内容进行反复理解,可以帮助R语言的学习。
注3:如遇到不准确之处,请在本贴的后面进行回帖,我们会逐渐进行修订。
|