Project Management

Half-life of knowledge

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What is the half-life of knowledge and how is it affecting us project people. Plus five tips on how to best handle it. And a huge plot twist at the very end.

The wild sixties

In my opinion, you have to start from the very beginning to understand something. In our case that means we have to go to the year 1962 Not only did cars look really good at the time, but this year Fritz Machlup also postulated the concept of "half-life of knowledge". Machlup - one of many Austrians chased away in the dark 1930s - was one of the first to understand knowledge as a resource. The term information society goes back to him. And just in 1962, based on the half-life that we know from physics, he defined a key figure: the time that passes until half of our acquired knowledge has become obsolete or wrong.


At the risk of undermining myself in the second paragraph of this article. But it has to be said that the concept of half-life of knowledge is not free of criticism. Mainly, that the concept is simple and generalizing. And yes, that is partly true. Sure, such a knowledge obsolescence is highly dependent on the particular subject area. Knowing how to recognize rock formations will not be as fast-paced as expertise in IT. And often we also find huge differences within one subject area. The knowledge of a web developer will be outdated faster than that of a mainframe software developer.

But we have to be careful here: sometimes outdated knowledge will still help me to squeak through work. I can often observe this attitude with people who have huge comfort zones. And yes, there are environments, where the 50%, leftover from my initial knowledge acquisition is enough to get the job done. Is that great? Or rather sad? Everybody has to decide for themselves. But the fact is: even in these areas, there is still something like a half-life of knowledge. It only has a smaller effect than perhaps elsewhere.

In any case

In any case, one thing is true. And I know, I am mentioning this often and at any opportunity. The world is turning ever faster. So I hope that here and now no one contradicts me:

Our acquired technical knowledge will be usable for shorter periods of time.

The half-life of knowledge was already very short for technical professions in 1962. At that time, it was said to be about 10 years. (Compared to 35 years in the 1930s.) Today, just 60 years later, it has become even shorter. And I do not want to go into more detail here on possible causes. I want to encourage you to think about the subject. In other words:

What does that mean for me?

Two things. First, let us have a look at the obvious: in the worst case, my team is constantly losing knowledge. And yes, I know that my wording is incorrect. The knowledge itself does not become less, it is less applicable. But in the end, it comes down to a loss of knowledge, if you are asking me. And that means that even the best knowledge sharing concept can only be half the battle. My two cents. Before I can share it, I have to have the knowledge. And if it is constantly losing its topicality, I have to make sure that my team, my organization has the ability to constantly acquire new knowledge. A learning organization

So we have to create an atmosphere that encourages knowledge acquisition. I can do that quite well with easy access to learning platforms and a time quota available for continuing education. I have often experienced a value of 10% to 15% of the working hours here. That sounds like a lot at first glance. Especially when a project is about to be completed. At second glance, and considering the half-life of knowledge, that seems like a reasonable value to me. And now it is crucial to motivate team members to take advantage of this offer. After all, it is in both their interests. And in my experience, the best motivation is the role model here. If I want to do things for the better, I have to lead by example.

The look into the mirror

So hopefully we have found a good approach for our team. With that and thus we are finished. Aren't we? Hm. Because of all the focus on others, we completely forgot about ourselves. We project people are just as affected by the loss of knowledge of course. Even more so than others who often work within teams with similar subject areas and topics. And how can we keep our knowledge up to date? Ideally, we can access the same structures our teams have. And if we are lucky, we are part of a Project Management Office, which ensures a lively exchange of knowledge and knowledge acquisition for us. In any case, it needs our awareness that we have to constantly practice knowledge hygiene here. That we constantly develop and change. (Here we are again with my favorite subject Kaizen.) We must not overlook this in the stressful everyday project life. Otherwise, at some point, the dust settles and we realize that all the others have moved on and we are left behind.

And how do I deal with that half-life of knowledge?

  1. Awareness. First, that there is something like the half-life of knowledge. Second, that this half-life of knowledge concerns our technical, not our "social" knowledge.
  2. Evaluation (environment, existing training, current knowledge, etc.), followed by a suitable strategy.
  3. Focusing on important knowledge. Unimportant one may erode. (Liechtenstein, for example, is the only country in the world where every football club has played at least once in the cup finals. Fascinating, isn't it? But completely unimportant. Except, if you are a professor at the chair of Liechtenstein Football History. And in case you have the urge to google "Liechtenstein" now: you propably have googled "Austria" already after reading where I come from. Liechtenstein is the tiny dot right left of it. And no, I am not talking about Switzerland.)
  4. Onwards, onwards, onwards. (I'm just writing this so I can mention Kaizen again. No, seriously: that is the single most important thing in our professional life.)
  5. And finally, a realization: "innate" skills are perhaps and more important than we are thinking. So we should have a special eye on that when it comes to employee selection.

As I said, the concept of half-life of knowledge also has critics. But maybe what was state-of-the-art in 1962 is not that up to date anymore. And so maybe the whole thing is proof in itself. Have fun thinking about this!

Posted on: August 04, 2019 02:37 PM | Permalink

Comments (4)

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Eduin Fernando Valdes Alvarado Project Manager| F y F Fabricamos Futuro Villavicencio, Meta, Colombia
Thanks for sharing

Mark Lotspaih IT Project Manager / Systems Administrator| Miamisburg City Schools Miamisburg, Oh, USA
I started to conceptualize something like this about 10 years ago when my local used bookstore enforced a new policy of not buying or selling information technology related books. The store manager told me that books related to information technology became outdated so quickly that they could not sell them. No one wanted out-dated knowledge! They wanted only the latest books.

Here's to lifelong learning!

Julie Ann Jones Lincs, Lincolnshire, United Kingdom
Thanks for sharing Stephan

Stephan Weinhold Scrum Master| ACI Worldwide Salzburg, Österreich, Austria
Thanks for your comments, guys!

Mark, you are a great observer. I for my part have stopped buying books on JavaScript. Even new ones. The moment they leave the press they are outdated...
And yes, lifelong learning (and livelong growing) should be standard today!

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