title: What does "replacement" mean in imbalanced learn RandomOverSampler?
body: <p>I am on imbalanced learn's <a href="https://imbalanced-learn.org/stable/references/generated/imblearn.over_sampling.RandomOverSampler.html" rel="nofollow noreferrer">documentation</a> reading about RandomOverSampler. The documentation says that RandomOverSampler is a</p>
  <blockquote>
  <p>Class to perform random over-sampling.
  Object to over-sample the minority class(es) by picking samples at random with replacement. The bootstrap can be generated in a smoothed manner.</p>
  </blockquote>
  <p>What does a replacement mean? Does it randomly duplicates samples from minority/majority class or is it something else?</p>