activity sampling

= work sampling

A technique in which a large number of observations are made over a period of a group of machines, processes, or workers. Each observation records what is happening at that instant; the percentage of observations recorded for a particular activity enables the total time during which that activity is occurring to be predicted. Traditionally carried out by industrial engineers using manual recording systems, this technique used to be dependent on the correct calculation of the number of observations required to give statistically valid data. Increasing use of on-line computerized data now enables managers to account for every second of their staff's time. The technique is particularly suitable for such processes as phone selling, customer services, etc. It can, however, also be applied in manufacturing systems and to groups, e. g. by requiring teams to bar-code themselves into a work area.