LABORATORY STUDIES OF REPETITIVE WORK. II : PROGRESS REPORT ON RESULTS FROM TWO SUBJECTS

Abstract

This experiment is the first or a series undertaken to test proposals put forward earlier by the first author that in repetitive work (i) output would be higher and variability less if breaks were given at the end of an actite period (period of optimum performance) rather than at the point when output decreased; (ii) the end of an actile period would be indicated by the onset of irregularity in performance which could be determined by the incidence longcycle times in unpaced work and an increase in the number of missed cycles in paced work; and (iii) the length of an actile period will depend on the demand made by the job and upon the capacity of the worker to meet the demand (her actility) Results from two subjects tested for a period of 3 1/ 2 months suggest that proposal (i) is correct. A condition in which two breaks were given at limes indicated by an increase in long times in unpaced performance gave a significantly better output and lower variance than a condition in which one break was given at a time indicated by a fall in output. Both subjects had relatively fewer misses in the paced condition when three breaks were given than when working continuously The technique for obtaining long times in unpaced work which formed part of (ii) was found to be practical and a simpler method was devised. The results obtained seem to confirm that the method has validity. No definite conclusions can be drawn on paced work There is some tentative confirmation of (iii); in the paced condition the actile period seems to have been 1 hour compared with 1 1/4hours in the unpaced condition. Further, the better worker gave her best unpaced performance when rest was given after 1 1/4 hours whereas the less good worker did best when rest was given after 1 hour.