title: Confidence intervals of loadings in principal components in R
body: <p>I am using following code for principal component analysis of first 4 columns of iris data set using prcomp function in R:</p>
  
  <pre><code>&gt; prcomp(iris[1:4])
  Standard deviations:
  [1] 2.0562689 0.4926162 0.2796596 0.1543862
  
  Rotation:
                       PC1         PC2         PC3        PC4
  Sepal.Length  0.36138659 -0.65658877  0.58202985  0.3154872
  Sepal.Width  -0.08452251 -0.73016143 -0.59791083 -0.3197231
  Petal.Length  0.85667061  0.17337266 -0.07623608 -0.4798390
  Petal.Width   0.35828920  0.07548102 -0.54583143  0.7536574
  </code></pre>
  
  <p>How can I get confidence intervals of these values in R? Is there any package that can do it? Thanks for your help.</p>