W. T. Williams

William Thomas Williams FAA OBE (18 April 1913 – 15 October 1995) was an English and Australian botanist and plant taxonomist, known for his work on algorithms for numerical taxonomy.

Biography Williams was born 18 April 1913 in Fulham, London, England, the only child of a Welsh coal miner.

Williams and Lance also introduced the Canberra distance, a form of Manhattan distance between pairs of points normalised by dividing by the total Manhattan distance of the points from the origin. The normalisation makes this distance measure particularly suited for data sets in which some data values may significantly differ from the rest.

Recognizing the general applicability of these methods, Williams went on at CSIRO to apply them to problems other than plant taxonomy, as well as to the classification of angiosperms and grasses. In this work, he viewed numerical taxonomy as a form of exploratory data analysis, intended more to generate new hypotheses than to confirm them.

Other activities Williams was an avid composer of mathematical puzzles; for instance, he wrote the cross-figure puzzle "The Little Pigley Farm" (also known as Dog's Mead, Little Pigley, Little Piggly Farm, Little Pigsby, Pilgrims' Plot, or Dog Days) which he first published in 1935 in The Strand Magazine.

Long a self-taught piano player, Williams took lessons after moving to Australia, earned a credential, and taught piano himself. He also organised the first North Queensland Piano Competition.

Awards and honours In 1973, the University of Queensland awarded Williams an honorary doctorate. He was elected as a fellow of the Australian Academy of Science in 1978, and in 1980 he became an officer of the Order of the British Empire.