ABSTRACT
A fall of output at the end of a work spell may not indicate any fatigue whatever, if the worker is in the habit of slowing down when he has done what he considers to be enough work. A fall of output in the latter part of the week may similarly be due to intentional limitation rather than to fatigue. The ratio of the extreme values was practically constant throughout, and at each period the quickest workers, in their best weeks, achieved about 22 times the hourly output of the slowest workers in their worst weeks. If the workers engaged on a given operation depart from the principle of always doing their best, and by some mutual arrangement limit their output to an agreed figure, it is evident that the distribution of their output values will no longer conform to the laws of probability.
