166 A. T. Welford 



his extensive and important study of industrial workers in 

 Holland. 



(b) It can be argued that if productivity figures are in- 

 validated by progressive selection in favour of the most able, 

 the age distribution of the men remaining on the job should 

 give an indication of whether capacity to do the operation 

 remains high with advancing age or declines. The age distri- 

 bution for a job may, of course, be affected by factors such 

 as age policies in the factory concerned or the age structure of 

 the local population, but comparing the age distribution of one 

 job, or group of jobs, with another in the same factory would 

 seem to be a possible method of obtaining data on capacity 

 in relation to operation. The data is crude, lacking all the 

 subtleties of detailed studies of actual work done, but is a 

 better method to use than production figures when labour 

 turnover is high. 



Age distributions may, however, be misleading if, as often 

 happens, there is a policy of recruiting young people in 

 preference to older, because they will then be dependent upon 

 the history of the job. If the job has expanded, the age 

 distribution will have too many at the young end; if it has 

 contracted, too many at the old. It will for the same reason 

 also be affected by such factors as the availability of labour in 

 the district and competition with other jobs. Even where 

 such a recruitment policy is absent, it may be difficult to 

 decide whether a shortage of older people on a job is due to 

 their failing to maintain performance or to their finding 

 difficulty in learning the job with consequent restriction of 

 placement. Age distributions are, however, by far the easiest 

 industrial data to obtain and would seem capable of giving 

 valuable preliminary information for comparing one class of 

 job with another provided due precautions are taken to ensure 

 that the recruitment policy and history is similar for both. 

 Work by Murrell, Griew and Tucker (1956) has provided a 

 striking example of stability in differences of age distribution 

 between jobs over a period of eight years in a situation where 

 there was no ascertainable selective placement. 



