such tools is itself a system and is, therefore, a reasonable domain for the kinds of systems research carried out by human factors scientists.
There are many ways in which human factors research is and continues to be useful in addressing some of the problems that now are being confronted by the people engaged in providing job-oriented training. In the rest of this chapter, we will explore these problems and the current and potential contribution of human factors to them.
The very nature of work is changing. Instead of the physical manipulations that formerly characterized most industrial jobs, more and more jobs are based on the manipulation of symbols—words and numbers. New technologies and work processes are shifting skill requirements in some types of jobs from manual and job-specific to generic, from concrete to abstract. For example, in many modern factories, the production process is so computerized that many workers no longer physically execute tasks but are now responsible mainly for monitoring automated processes. Whereas previously a machinist adjusted and maintained machinery by hands-on manipulation, today a technician works through a keyboard and CRT display and consequently has a more distant relationship to both process and product.
A direct consequence of computerization is that tangible work outcomes are less evident. There is some evidence suggesting that spontaneous learning and skill transfer do not work as well in highly computerized environments as in more traditional workplaces. For example, the difference in performance between the best and the average appears to be greater in computerized work than in traditional jobs. This finding leads to the conjecture that less incidental or informal learning takes place in work that involves symbol manipulation. This conjecture is supported by the fact that much about symbol manipulation is invisible, unlike the visible actions involved in object manipulation. The findings also suggest that John Seely Brown (1988) and others are correct when they call for new forms of training such as a "cognitive apprenticeship," which would somehow make the mental procedures and decision processes of exemplary performers "visible" so that others might learn from them.
Similar concerns are expressed about the changing demographics of the workforce. In this era of vigorous global competition, rapid technological