A tale of two biases

At the moment I’ve two major projects on my desk. One is launched, a large study which requires the recruitment of a large number of participants. This project is kicking off after a lot of planning, and we need to make sure we stay on track and make good decisions as things evolve. The second is in the planning stage, a large research grant application involving multiple collaborators. I really want these both to go well – they are significant steps forward for both me and the partners involved.

As with all projects, budgetary pressures are present in both cases. We need to get the job done, but can’t over-resource the problem. Both are time sensitive, the former to get completed to an agreed timescale, the other to avoid the ideas becoming stale and unfundable. For both, I am working with a small internal project team whom I’ve worked closely with for years. One lesson psychology has taught me is that this common combination of factors – high pressure, a lot to keep track of (’cognitive load’), planning and monitoring requirements, and a small cohesive group, is a potential recipe for, if not disaster, then certainly less than optimal performance. Why? It exposes us to the effects of a number of potential cognitive biases which can affect decision making.

The one I am most aware of before and at the start of a project is the planning fallacy, and it’s nefarious cousin, optimistic bias. Both were identified by Daniel Kahneman and Amsos Tversky. The planning fallacy reflects a tendency to underestimate the time and effort required to reach a goal, even when such requirements are blinding obvious to outsiders. Indeed, we can quite cheerfully realize others plans underestimate resources, whilst misjudging our own. A neat study(1) which demonstrates this asked PhD students how long they estimated it would take themselves to write their final thesis, over both best, expected and worst case periods. On average, these students estimated 48.6 days as worse case, but it actually ended up being 55.5 days on average. This effect arises in part due to a related phenomena – optimistic bias- this is the tendency to see yourself as less likely to encounter negative outcomes than other people, and more likely to receive positive ones. This effect basis our judgments in domains such as health (for instance, being less likely to get cancer from smoking), gambling (being able to beat the house, in the full knowledge that the odds are stacked against one) or, in this case, the likelihood that things which may or may not happen to advance a project, will. There are ways to reduce the planning fallacy – for instance, to segment tasks up when evaluating time and energy requirements – this firstly makes you evaluate things in more detail, and also makes you realize the extent elements are dependent on one another. Another is to have an external evaluation of your estimates (and, importantly, listen to the answer). Fingers crossed, we’ve done this sufficiently well to have a couple of smooth running projects (of course, it’s me, so it’ll be fine yes?!!).



(1) Buehler, R., Griffine, D., Ross, M (1994). Exploring the planning fallacy”: Why people underestimate their task completion times: Journal of Personality and Social Psychology, 67, 366-381.

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