the fit result below:
Call:
lm(formula = y ~ x1 + x2 + x3, data = pc)
Residuals:
Min 1Q Median 3Q Max
-1.29638 -0.47622 0.01059 0.49268 1.69335
Coefficients:
Estimate Std. Error t value Pr(>|t|)
(Intercept) 5.613e+00 8.143e-02 68.932 < 2e-16 ***
x1 -3.089e-05 5.150e-06 -5.998 8.58e-08 ***
x2 -4.095e-05 3.448e-05 -1.188 0.239
x3 -8.106e-05 6.412e-05 -1.264 0.210
---
Signif. codes: 0 ?***? 0.001 ?**? 0.01 ?*? 0.05 ?.? 0.1 ? ? 1
Residual standard error: 0.691 on 68 degrees of freedom
Multiple R-squared: 0.3644, Adjusted R-squared: 0.3364
F-statistic: 12.99 on 3 and 68 DF, p-value: 8.368e-07
x2,x3 is not significance. by pricipal, after PCA, the pcs should
significance, but my data is not, why?