THE OCCURRENCE AND EFFECT OF LOCKOUT 



267 



any definite relation between the lockout rate and repetition rate, al- 

 though in most cases an increase in lockout rate results in an increase 

 in repetition rate. If we exclude from consideration those cases in 

 which the lockouts are of very short duration and in which releasing 

 lockouts occur, the data indicate a somewhat closer dependence of repe- 

 tition rate on lockout rate. This suggests that the increase in repeti- 

 tion rate caused by lockouts may be proportional to the duration of 

 lockouts and to their frequency of occurrence, or to the per cent of 

 time which is locked out. Fig. 3, which shows the repetition rates. 



1.5 2.0 2.5 3.0 3.5 



PER CENT OF TIME LOCKED OUT 



Fig. 3 — Observed variation of corrected repetition rate with per cent of 

 time locked out. 



corrected for seasonal variations, plotted against the per cent of time 

 locked out, indicates a reasonable agreement with this assumption. 

 The correction is applied by subtracting from the observed repetition 

 rate the difference between the observed repetition rate for the appro- 

 priate reference or n condition and a rate of 0.36, arbitrarily chosen as 

 equal to the lowest repetition rate observed on any of the n conditions. 

 All of the data are included in this figure. The dashed lines are drawn 

 to include all the data and have a slope estimated as average from 

 considering the data in individual groups. The variability in the data 

 may in part be attributed to the variation in the distribution of lockout 

 durations, since if two distributions have the same mean value but 

 different spreads, the lockouts comprising the distribution which in- 

 cludes a greater number of long lockouts might be expected to have a 

 greater effect upon the repetition rate. With due allowance for the 

 variability of the data, Fig. 3 indicates that the repetition rate 

 increases proportionally with the per cent of time locked out except 



