epoh 发表于 2010-9-30 10:23 
library(tsDyn)
x
请教:epoh
看
http://127.0.0.1:28317/library/tseries/html/arma.html
的例子出了问题!!!
一、以下是网页上其中的例子:
See Also
summary.arma for summarizing ARMA model fits; arma-methods for further methods; arima0, ar.
Examples
1、data(nino)
2、s<-nino3.4
3、summary(s.arma<-arma(s,order=c(20,0)))
4、summary(s.arma<-arma(s,lag=list(ar=c(1,3,7,10,12,13,16,17,19),ma=NULL)))
5、acf(residuals(s.arma),na.action=na.remove)
6、pacf(residuals(s.arma),na.action=na.remove)
7、summary(s.arma<-arma(s,lag=list(ar=c(1,3,7,10,12,13,16,17,19),ma=12)))
8、summary(s.arma<-arma(s,lag=list(ar=c(1,3,7,10,12,13,16,17),ma=12)))
9、plot(s.arma)
***********************************************************************************
二、我照着以上的例子来实验有如下的结果:> data(nino)
> s<-nino3.4
> summary(s.arma<-arma(s,order=c(20,0)))
Call:
arma(x = s, order = c(20, 0))
Model:
ARMA(20,0)
Residuals:
Min 1Q Median 3Q Max
-1.378647 -0.223040 0.007358 0.215996 1.103511
Coefficient(s):
Estimate Std. Error t value Pr(>|t|)
ar1 1.10163 0.04090 26.932 < 2e-16 ***
ar2 -0.05461 0.06063 -0.901 0.367693
ar3 -0.17718 0.06060 -2.924 0.003457 **
ar4 0.07072 0.06056 1.168 0.242900
ar5 -0.05292 0.05990 -0.884 0.376941
ar6 0.06743 0.05932 1.137 0.255661
ar7 -0.17060 0.05877 -2.903 0.003698 **
ar8 -0.03509 0.05857 -0.599 0.549068
ar9 0.03326 0.05827 0.571 0.568113
ar10 0.14149 0.05829 2.427 0.015206 *
ar11 0.01597 0.05812 0.275 0.783504
ar12 0.16400 0.05791 2.832 0.004629 **
ar13 -0.22467 0.05833 -3.852 0.000117 ***
ar14 -0.01355 0.05869 -0.231 0.817394
ar15 -0.04530 0.05845 -0.775 0.438283
ar16 -0.18815 0.05807 -3.240 0.001196 **
ar17 0.20923 0.05868 3.566 0.000363 ***
ar18 0.07387 0.05868 1.259 0.208074
ar19 -0.13363 0.05792 -2.307 0.021045 *
ar20 0.05234 0.04002 1.308 0.190952
intercept 4.46824 0.79612 5.613 1.99e-08 ***
---
Signif. codes: 0 ‘***’ 0.001 ‘**’ 0.01 ‘*’ 0.05 ‘.’ 0.1 ‘ ’ 1
Fit:
sigma^2 estimated as 0.1079, Conditional Sum-of-Squares = 62.24, AIC = 407.41
>summary(s.arma<-arma(s,lag=list(ar=c(1,3,7,10,12,13,16,17,19),ma=NULL)))
Call:
arma(x = s, lag = list(ar = c(1, 3, 7, 10, 12, 13, 16, 17, 19), ma = NULL))
Model:
ARMA(19,0)
Residuals:
Min 1Q Median 3Q Max
-1.360875 -0.230887 0.005043 0.226822 1.090989
Coefficient(s):
Estimate Std. Error t value Pr(>|t|)
ar1 1.07772 0.02642 40.793 < 2e-16 ***
ar3 -0.16942 0.03016 -5.618 1.93e-08 ***
ar7 -0.13913 0.02254 -6.174 6.67e-10 ***
ar10 0.16459 0.02931 5.615 1.97e-08 ***
ar12 0.20472 0.04754 4.306 1.66e-05 ***
ar13 -0.29976 0.04133 -7.253 4.07e-13 ***
ar16 -0.21637 0.04349 -4.975 6.54e-07 ***
ar17 0.25139 0.04648 5.408 6.37e-08 ***
ar19 -0.04510 0.02580 -1.748 0.0804 .
intercept 4.61896 0.77687 5.946 2.75e-09 ***
---
Signif. codes: 0 ‘***’ 0.001 ‘**’ 0.01 ‘*’ 0.05 ‘.’ 0.1 ‘ ’ 1
Fit:
sigma^2 estimated as 0.1094, Conditional Sum-of-Squares = 63.24, AIC = 393.87
警告信息:
In arma(s,lag=list(ar=c(1,3,7,10,12,13,16,17,19),ma=NULL)) :
order is ignored
册除ar19,再一次操作
>summary(s.arma<-arma(s,lag=list(ar=c(1,3,7,10,12,13,16,17),ma=NULL)))
Call:
arma(x = s, lag = list(ar = c(1, 3, 7, 10, 12, 13, 16, 17), ma = NULL))
Model:
ARMA(17,0)
Residuals:
Min 1Q Median 3Q Max
-1.3866267 -0.2350164 -0.0007791 0.2283570 1.0824308
Coefficient(s):
Estimate Std. Error t value Pr(>|t|)
ar1 1.06130 0.02580 41.137 < 2e-16 ***
ar3 -0.14112 0.02764 -5.105 3.31e-07 ***
ar7 -0.15045 0.02201 -6.835 8.22e-12 ***
ar10 0.15700 0.02921 5.375 7.64e-08 ***
ar12 0.22580 0.04693 4.812 1.50e-06 ***
ar13 -0.30550 0.04144 -7.373 1.67e-13 ***
ar16 -0.20657 0.04298 -4.806 1.54e-06 ***
ar17 0.20237 0.03788 5.342 9.19e-08 ***
intercept 4.23763 0.73063 5.800 6.63e-09 ***
---
Signif. codes: 0 ‘***’ 0.001 ‘**’ 0.01 ‘*’ 0.05 ‘.’ 0.1 ‘ ’ 1
Fit:
sigma^2 estimated as 0.11, Conditional Sum-of-Squares = 63.81, AIC = 395.16
警告信息:
In arma(s, lag = list(ar = c(1, 3, 7, 10, 12, 13, 16, 17), ma = NULL)) :
order is ignored
问题:
1、为什么网页的教程没有出现警告信息。
2、是不是分析包有所的改变?
3、如何改动:arma(s, lag = list(ar = c(1, 3, 7, 10, 12, 13, 16, 17), ma = NULL)) 的语句才不会出现错误!
4、在例子一第一句中:
summary(s.arma<-arma(s,order=c(20,0))),是不考虑有MA(p)的情况。如何我们要考虑MA(P)的情况,变成语句:(p=1)
> summary(s.arma<-arma(s,order=c(20,1)))
则显示错误:
错误于optim(coef, err, gr = NULL, hessian = TRUE, ...) : optim回覆了无限值。
请问如我要考虑MA(P)的情况,则上述语句如何改!谢谢!