12.3.7. Vera Kublanovskaya

Vera Nikolaevna Kublanovskaya (1920–2012) independently developed the QR algorithm to solve the eigenvalue problem. She is usually not given the same level of recognition for doing so as John Francis. There are a few reasons for this.

  1. She published her algorithm after Francis did. There is no doubt that she was on an independent but parallel path to Francis. Like Francis, she cited Rutishauser’s LR algorithm (The LR Algorithm) as similar to her algorithm, except that she uses unitary transformations. Nevertheless, more credit is usually given to the first one to publish.
  2. She had no computer access to write a program to run her algorithm. She verified her algorithm with hand-written manual calculations.
  3. Her algorithm was the same as Francis’s first QR algorithm. Francis’s second algorithm, QR with implicit shifts (now called the Francis algorithm), is the better algorithm.
  4. Being in the Soviet Union, her publications may have been more obscure to researchers in other countries.