Avoiding the “Sunk Cost Fallacy” in Your Post-Ph.D. Career Choice

 In PhD/Postdoc Blog

Totally irrational

“Sunk costs are sunk,” or so the saying goes. We can probably all relate to the experience of going to the theater on our artsy aunt’s film recommendation and realizing in the first five minutes that, “this definitely isn’t for me.” Don’t worry; we’ve all been there… Rather than discreetly exiting the theater though, you probably felt obligated to keep watching. The longer you suffered through it, the stronger your resolve. “I’ve paid for the ticket, and I’ve already watched 90 minutes! I will get my money’s worth,” you bitterly thought to yourself. Unfortunately, watching the whole of that terrible film makes you as good at decision-making as a rodent (Sweis et al. Science, 2018). So what are sunk costs and why am I writing about them in a careers blog?

In the field of behavioral economics, the sunk cost fallacy was investigated by the Nobel laureate Daniel Kahneman and his collaborator Amos Tversky. The sunk cost fallacy, along with other expositions of our irrational decision-making, are described in Kahneman’s bestselling book, Thinking Fast and Slow (Kahneman, 2011). This book should absolutely be required reading for anyone considering a career in science, and expertly lays out implicit human biases and cognitive pitfalls, but I digress. Basically, the sunk cost fallacy states that because we are typically risk-averse, we are more likely to make decisions based on costs that we have already incurred (sunk costs), rather than on unknown prospective costs. Ergo, the more resources we expend on a given activity, the more valuable we perceive it to be and the more likely we are to let that perceived increase in value influence our further decision-making, i.e., the longer we sit through that movie, the more we feel like we have to get to the end.

Overcome the cognitive bias

So now we need to ask ourselves whether we are falling victim to the sunk cost fallacy when it comes to our career decisions. Let’s face it, a career in academia is a huge investment, both with regards to time and money. You may spend 3-5 years as an undergraduate, 1-2 years as a masters student, and another 3-6 years pursuing your Ph.D. So, after potentially 13 years of training and research experience, you come to a bifurcation point in your career: to postdoc or not to postdoc? The answer, “maybe,” and that is entirely your decision. I’m not here to tell you what the right or wrong choice is; that’s the problem with this ‘n’ of one experiment that we call life. My hope is that in reading this, you are better able to critically evaluate your own career choices without being influenced by sunk costs. The point here is that to make a rational decision on the next step of your career, you have to consider that the time already committed on your scientific endeavors up until this point is spent; the sunk costs are sunk. This commitment to academic research should not bias your decision to take on the challenge of a postdoc, or pick a new challenge.

Forget the sunk costs

Several weeks ago, I went to a seminar at the public library hosted by the owners of two local breweries. Following the talk, I got to chatting with one of the owners and was surprised to find that she had been working as a postdoc in microbiology at one of the local universities prior to setting up the brewery. Whether you plan to take up the position of postdoc, transition to scientific writing, move to a job in consulting, or even set up a brewery, it is irrational to base your future career decisions on the costs that you have already incurred in your scientific career. You should not feel obligated to trudge along the path of an academic postdoc just because you have already sunk a lot of time into getting there, nor indeed should you feel obligated to pursue a career in research just because it would seem wasteful not to at this point. You do not cease to be a scientist once you leave academia. This is something that we would do well to remind ourselves every once in a while. The skills and the mindset that you develop along the way do not get taken away and stored with your old lab notebooks when you leave your university. Science is a philosophy and provides us with a set of tools for interpreting the world. These can just as easily be applied to any other endeavor as they can to research.

Now that you are well-versed in the sunk costs fallacy, I hope that you will go forth and make more rational choices when it comes to your future career. And, more importantly, stop taking film advice from your aunt!

For more unsolicited career advice follow me on twitter @SciMJHarris and keep up-to-date with the rest of the team @NIHBest.


Sweis, B. M., Abram, S. V., Schmidt, B. J., Seeland, K.D., MacDonald III, A.W., Thomas, M.J., Redish, D. A., Sensitivity to “sunk costs” in mice, rats, and humans. Science 13 July, 2018 Vol. 361, Issue 6398, pp. 178-181 DOI: 10.1126/science.aar8644 

Kahneman, D. (2011). Thinking, fast and slow. New York: Farrar, Straus and Giroux.

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Showing 3 comments
  • Laura Daniel

    I enjoyed the perspective of sunk cost with regard to career choices.

    The sunk cost fallacy is also important for us as scientists to think about with regards to our experiments, projects, and PIs. The longer we try to address problems we are having with either, the more determined we are to trudge through and hope we will eventually see the end.

    Don’t let time spent on things determine whether you will maintain the course.

  • Wangui Mbuguiro

    I really liked the point about how we don’t cease to be a scientist after leaving academia. Adjusting the focus from perceived losses to tangible gains may help anyone overwhelmed with ‘sunk costs.’ I enjoyed the way you described the tangible gains of studying science.

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  • […] So, where am I going from here? Will I preserver and win the tenure-track lottery? Do I even want the tenure-track life (there are a lot of pros and cons)? If I move into a career outside academic research and teaching, was my postdoc a waste? Of course not (more on this point in next month’s point). Along this line of thinking, I recommend you check out Michael Harris’s BEST blog piece on the “Sunk Cost Fallacy.” […]

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