An Engineering Career: Only a Young Person’s Game?

Half-life of knowledge pressures employers to seek out young engineers

5 min read
An Engineering Career: Only a Young Person’s Game?
Andrew Rich/Getty Images

If you are an engineer (or a computer professional, for that matter), the danger of becoming technologically obsolete is an ever-growing risk. To be an engineer is to accept the fact that at some future time—always sooner than one expects—most of the technical knowledge you once worked hard to master will be obsolete.

An engineer’s “half-life of knowledge,” an expression coined in 1962 by economist Fritz Machlup to describe the time it takes for half the knowledge in a particular domain to be superseded, everyone seems to agree, has been steadily dropping. For instance, a 1966 story in IEEE Spectrum titled, “Technical Obsolescence,” postulated that the half-life of an engineering degree in the late 1920’s was about 35 years; for a degree from 1960, it was thought to be about a decade.

Thomas Jones, then an IEEE Fellow and President of the University of South Carolina wrote a paper in 1966 for the IEEE Transactions on Aerospace and Electronic Systems titled, “The Dollars and Cents of Continuing Education,” in which he agreed with the 10 year half-life estimate. Jones went on to roughly calculate what effort it would take for a working engineer to remain current in his or her field.

Jones postulated that a typical undergraduate engineer invested some 40 hours a week of study over 120 weeks in his or her degree, or about 4800 hours total. Assuming a half-life of 10 years, Jones said about 2400 hours of undergraduate knowledge has probably been superseded. To replace that obsolete knowledge and assuming there was 48 weeks a year in which to devote on knowledge replacement, Jones reasoned that an engineer would need to spend 5 hours each of those weeks gaining new technology, mathematics and scientific knowledge if he or she wished to remain technically current. That, of course, assumed the engineer didn’t forget any previously learned knowledge that was still relevant.

Jones emphasized in his article that, “Life-long learning of engineering is possible only by disciplined life-long study and thought.” Over a 40 year engineering career, a person would need to spend 9600 hours in study to remain current, or the time needed to earn two undergraduate degrees.

Jones hinted in his paper about the continuing issue of accelerating “knowledge decay,” which can be seen rising again as an issue in a 1991 New York Times article, “Engineer Supply Affects America.” The Times article cites the IEEE as a source when it  reported that the half-life of engineering skills at that time was now estimated to be less than 5 years, and for a software engineer, it was less than three. A few years later in 1996, Craig Barrett, president and co-founder of Intel, lent credence to that belief when he stated, “The half-life of an engineer, software or hardware, is only a few years.” In 2002, William Wulf, the president of the National Academy of Engineering, was quoted as saying that,” The half-life of engineering knowledge… is from seven to 2½ years.” More recent estimates emphasize the low end of the range, especially for those working in IT.

Philippe Kruchten, a thirty-year software engineering practitioner and manager before he became a professor of software engineering at the University of British Columbia in Vancouver, took an informal stab in 2008 at the half-life of software engineering ideas by re-examining 1988 issues of IEEE Software and trying to see which “are still important today or at least recognizable.” Kruchten conjectured in a paper he wrote for IEEE Software that the half-life of software engineering ideas is likely not much more than 5 years.

If we take Krutchen’s half-life of knowledge of 5 years estimate, and apply Jones’s formula, an engineer or IT professional today would have to spend roughly 10 hours a week studying new knowledge to stay current (or upskilling, in the current lingo). One may quibble that your study productivity is much higher than when you were in college or university, but even cutting the time needed by a quarter to 7.5 hours a week of intense study 48 weeks every year that Jones said was needed in 1966 would tax many working engineers and IT professionals today. The workload needed to keep current helps explain why the half-life of an engineer or IT professional’s career is now about 10 to 12 years or even less.

The perception of technology obsolescence especially in experienced (aka older) engineers and IT professionals is one of primary reasons that employers give in pushing for the hiring of young engineers, IT professionals and H-1B visa workers. Mark Zukerberg, CEO of Facebook, who is one of many high tech employers pushing for more H-1B visas, reflects the prevailing attitude when he stated both that, “Our policy is literally to hire as many talented engineers as we can find. The whole limit in the system is that there aren't enough people who are trained and have these skills today,” and “I want to stress the importance of being young and technical. Young people are just smarter. Young people just have simpler lives. We may not own a car. We may not have family. Simplicity in life allows you to focus on what's important.

As Zukerberg indicates, a highly desirable “skill” in young engineers and computer professionals is their perceived willingness to work longer and harder than older workers who usually have families, as well as their perceived willingness to relocate. Obviously, all that extra work leaves little time for disciplined study and thought to stay current beyond today's belief of "what's important."

Of course, there is also that critical matter of pay: younger engineers and IT professionals earn significantly less than one who is experienced. Given a choice, many employers would rather hire a couple of inexperienced computer programmer and spend a few months training them than hiring (or retaining) a more experienced but expensive programmer. As academic cum entrepreneur Vivek Wadhwa writes, “the harsh reality is that in the tech world, companies prefer to hire young, inexperienced, engineers” over more experienced ones.

In addition, many employers aren’t interested in providing training to engineers or programmers who may start becoming obsolete, for fear of seeing them leave or be poached for employment elsewhere. Peter Cappelli, a professor of management at Wharton and one who has published a book on employer hiring and (non)training practices, indicated to Spectrum last year that employers looking for experienced workers have fallen into the habit of poaching employees from their competitors as opposed to spending the resources to train from within their organization to meet a specific job skill.

You can further see the youth-driven dynamics at work by looking at the median age of employees at technology companies. The New York Times recently ran a story on a study conducted by PayScale, a company based in Seattle, which found that of the 32 most successful companies in the technology industry, only six had a median age greater than 35 years old. Eight of the companies, Payscale found, had a median age of 30 or younger. Facebook, for instance, had a median age of 28 years old, while IBM Global Services in comparison had a median age of 38 years old.

What can be done if you are an older engineer or computer professional? Well, you can look at Payscale’s companies’ median ages and try to target those where the median age is older than your age. You could do what some older engineers and computer professionals are doing in Silicon Valley, and try to hide your age by dressing younger, hide your graying hair, carry all the latest high tech gear in a backpack, and even get eyelid lifts. You could also try to increase your business acumen to try to convince your employer you are creating shareholder value. Or you may also just decide the best option is to spend time designing an escape plan and either aim for a job in management (assuming there is one) or get into another field altogether.

The only bit of schadenfreude for older engineers and computer programmers being pushed aside for younger ones is to know that it will happen to them too, but maybe at an even younger age. After all, that is what many of those getting pushed out today themselves did to engineers and IT professionals just slightly older than themselves back in 2000.

Photo: Andrew Rich/Getty Images

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