我正在运行简单回归（OLS）
> lm_1 <- lm(Dependent_variable_1 ~ Independent_variable_1, data = data_1)
> summary(lm_1)
Call:
lm(formula = Dependent_variable_1 ~ Independent_variable_1,
data = data_1)
Residuals:
Min 1Q Median 3Q Max
-143187 -34084 -4990 37524 136293
Coefficients:
Estimate Std. Error t value Pr(>|t|)
(Intercept) 330853 13016 25.418 < 2e-16 ***
`GDP YoY% - Base` 3164631 689599 4.589 0.000118 ***
---
Signif. codes: 0 ‘***’ 0.001 ‘**’ 0.01 ‘*’ 0.05 ‘.’ 0.1 ‘ ’ 1
Residual standard error: 66160 on 24 degrees of freedom
(4 observations deleted due to missingness)
Multiple R-squared: 0.4674, Adjusted R-squared: 0.4452
F-statistic: 21.06 on 1 and 24 DF, p-value: 0.0001181
自相关和异方差测试如下：
> dwtest(lm_1,alternative="two.sided")
Durbin-Watson test
data: lm_1
DW = 0.93914, p-value = 0.001591
alternative hypothesis: true autocorrelation is not 0
> bptest(lm_1)
studentized Breusch-Pagan test
data: lm_1
BP = 9.261, df = 1, p-value = 0.002341
然后我对自相关和异方差（HAC-Newey-West）进行了稳健的回归：
> coeftest(lm_1, vocv=NeweyWest(lm_1,lag=2, prewhite=FALSE))
t test of coefficients:
Estimate Std. Error t value Pr(>|t|)
(Intercept) 330853 13016 25.4185 < 2.2e-16 ***
Independent_variable_1 3164631 689599 4.5891 0.0001181 ***
---
Signif. codes: 0 ‘***’ 0.001 ‘**’ 0.01 ‘*’ 0.05 ‘.’ 0.1 ‘ ’ 1
对于系数/标准误差，我得到相同的结果。
这正常吗？这是由于样本量小吗？