How to generate the two time series of length 10000
#fix the random seed
> #define length of simulation
> N <- 10000
> #simulate a normal random walk
> x <- cumsum(rnorm(N))> #set an initial parameter value
> gamma <- 0.6
> #simulate the cointegrating series
> y <- gamma * x + rnorm(N)
> #plot the two series
> plot(x, type='l')
> lines(y,col="red")
# Augmented Dickey-Fuller Test Unit Root Test #
###############################################Test regression none
Call:
lm(formula = z.diff ~ z.lag.1 - 1 + z.diff.lag)
Residuals:
Min 1Q Median 3Q Max
-3.7583 -0.6800 -0.0105 0.6604 3.6463
Coefficients:
Estimate Std. Error t value
z.lag.1 -0.0008567 0.0004221 -2.030
z.diff.lag 0.0287582 0.0099989 2.876
Pr(>|t|)
z.lag.1 0.04241 *
z.diff.lag 0.00403 **
---
Signif. codes:
0 ‘***’ 0.001 ‘**’ 0.01 ‘*’ 0.05 ‘.’ 0.1 ‘ ’ 1
Residual standard error: 0.9956 on 9996 degrees of freedom
Multiple R-squared: 0.001212, Adjusted R-squared: 0.001012
F-statistic: 6.067 on 2 and 9996 DF, p-value: 0.002328
Value of test-statistic is: -2.0297
Critical values for test statistics:
1pct 5pct 10pct
tau1 -2.58 -1.95 -1.62
Augmented Dickey-Fuller Test Unit Root Test #
###############################################Test regression none
Call:
lm(formula = z.diff ~ z.lag.1 - 1 + z.diff.lag)
Residuals:
Min 1Q Median 3Q Max
-5.4824 -0.9477 -0.0207 0.9182 5.1281
Coefficients:
Estimate Std. Error t value
z.lag.1 -0.0032685 0.0009824 -3.327
z.diff.lag -0.4303026 0.0090285 -47.661
Pr(>|t|)
z.lag.1 0.000881 ***
z.diff.lag < 2e-16 ***
---
Signif. codes:
0 ‘***’ 0.001 ‘**’ 0.01 ‘*’ 0.05 ‘.’ 0.1 ‘ ’ 1
Residual standard error: 1.392 on 9996 degrees of freedom
Multiple R-squared: 0.1875, Adjusted R-squared: 0.1874
F-statistic: 1154 on 2 and 9996 DF, p-value: < 2.2e-16
Value of test-statistic is: -3.3269
Critical values for test statistics:
1pct 5pct 10pct
tau1 -2.58 -1.95 -1.62
#take a linear combination of the series
> z = y - gamma*x> plot(z,type='l')
summary(ur.df(z,type="none"))
###############################################
# Augmented Dickey-Fuller Test Unit Root Test #
###############################################
Test regression none
Call:
lm(formula = z.diff ~ z.lag.1 - 1 + z.diff.lag)
Residuals:
Min 1Q Median 3Q Max
-3.6372 -0.6856 -0.0036 0.6590 3.5004
Coefficients:
Estimate Std. Error t value
z.lag.1 -0.99967 0.01423 -70.250
z.diff.lag -0.01232 0.01000 -1.232
Pr(>|t|)
z.lag.1 <2e-16 ***
z.diff.lag 0.218
---
Signif. codes:
0 ‘***’ 0.001 ‘**’ 0.01 ‘*’ 0.05 ‘.’
0.1 ‘ ’ 1
Residual standard error: 0.9983 on 9996 degrees of freedom
Multiple R-squared: 0.5061, Adjusted R-squared: 0.506
F-statistic: 5121 on 2 and 9996 DF, p-value: < 2.2e-16
Value of test-statistic is: -70.2499
Critical values for test statistics:
1pct 5pct 10pct
tau1 -2.58 -1.95 -1.62
0 Comments