Editing Principal component analysis (section)

=== Online/sequential estimation ===
In an "online" or "streaming" situation with data arriving piece by piece rather than being stored in a single batch, it is useful to make an estimate of the PCA projection that can be updated sequentially. This can be done efficiently, but requires different algorithms.<ref>{{Cite journal
  | last1 = Warmuth
  | first1 = M. K.
  | last2 = Kuzmin
  | first2 = D.
  | title = Randomized online PCA algorithms with regret bounds that are logarithmic in the dimension
  | journal = Journal of Machine Learning Research
  | volume = 9
  | pages = 2287–2320
  | year = 2008
  | url = http://www.jmlr.org/papers/volume9/warmuth08a/warmuth08a.pdf}}</ref>