Back to basics (21) - Least squares, statistics and all that

This is the eighth of a series of articles presenting some thoughts about L east Squares, Statistics Quality Control a,ln other related matters, which may be of interest to students, or practitioners new to the particular appl ications described. The treatment is deliberately elementary and the exampl es are simplified so that the various concepts can be developed with clarit y. Now and then, file editor will enter a word of caution in the text, wher e he feels that the treatment has been oversimplified or for other reasons. As in previous articles, the topic is presented as a dialogue between this practising surveyor Nigel Atkinson and a retired academic Arthur Allan. Th e editor encourages comments as the series unfolds.