TABLE OF CONTENTS Work sampling is based on the law of probability. It works because a smaller number of chance occurrences tends to follow the same distribution pattern that a larger number produces. Random work sampling and group timing technique (GTT), a fixed short-interval work sampling procedure, are both employed for work measurement and cost reduction analysis. These techniques can often replace traditional stopwatch time study, providing equal or better data at a lower cost.
Work sampling was introduced in England by a statistician, L. H. C. Tippett [1]. Its application was first applied to direct factory labor. Later it was employed to determine time utilization of office workers, teachers, management, as well as downtime and uptime of machines, material-handling equipment, and elevators. In the May 1953 issue of Time and Motion Study published in London, England, [2] Tippett reviews his experience:
Round about 1927,1 was making surveys in weaving sheds to discover the causes and durations of loom stoppages with a view to estimating how much of the productive capacity was lost for various causes. At first I used the obvious method of timing looms for long periods with a stopwatch. This caused no difficulty from the operators. No one thought of my activity as having any connection with time study as conventionally understood. The work was tedious, as it was practical to record only two, or three, or four looms at a time. I had to move about the...
