the sigma enigma

摘要

A statistical term for a measure of variation, as well as the brand name of Motorola's internal quality initiative in the late 1980s, six sigma propelled its founding company to greater profits and won many champions and more disciples. David Hutchins, chairman of David Hutchins International Ltd, argues that with its track record and influential backing, it was only a matter of time before six sigma appeared in the UKALLIED Signal claimed that its phenomenal turnaround was due to six sigma; Jack Welch, the high-profile chief executive of GE, took it on and GE is now the benchmark for the rest of industry. Nonetheless, at first sight six sigma appears to be nothing more than a particularly well-considered TQM initiative. There is nothing new in six sigma; its tools and techniques are rooted in the studies of people like Fisher, who published works on designed experiments up to the mid 1930s, and Walter W Shewhart, who invented statistical quality control.