I have been reading Rolf Dobelli’s book The Art of Thinking Clearly on systematic cognitive errors. It is a thoroughly readable romp (Dobelli is a novelist by trade) through many of the flaws in decision-making and judgement that human beings are prone to. It is not that we are completely irrational – just that we are not as rational and clear thinking as we like to believe we are. Like many, I first encountered ideas about cognitive biases and heuristics – common mental shortcuts used to side-step thinking about difficult problems – in Daniel Kahneman’s seminal work, Thinking: Fast and Slow. It is a must-read.
The routine cognitive errors shared in both books are largely inescapable. They are wired into our thinking, probably as evolutionary relics passed down genetically from our hunter-gatherer ancestors. Through careful self-control we can all get better at managing our own decisions, and because decision-making based on a complex range of variables is part-and-parcel of teaching and school management, I think a broader awareness of cognitive biases could prove particularly useful.
What follows are descriptions of three common cognitive errors, along with real and hypothetical school-based scenarios to exemplify their significance. For each, I also offer some tentative solutions.
1. Availability bias is the way we are susceptible to making evaluations based on the evidence that comes most immediately to mind.
Here’s an example. I have taught at my current school for nine years and, without fail, every few months I hear somebody say that they think that behaviour in the school is steadily deteriorating. I tend not commit to this conversation, mainly because I have judged the complete opposite to be true: I think behaviour has improved immeasurably.
Both our judgements, however, are likely to be tainted by availability bias. Perhaps my colleague has recently been the victim of several examples of poor behaviour in her lessons. These memories loom so large that she automatically links them together to form her judgement, forgetting about ninety-nine per cent of her pupils who have been consistently impeccable. Similarly, examples of good behaviour are more available to me because of two factors: 1) the longer I have remained at the school, the more established and confident I have become and 2) I have been extremely lucky with the behaviour profile of my classes over the last two years.
So, how do we find an answer much closer to the truth? We could look at school exclusion figures first. These would give a general picture but they might not fully tell us what we they think they do. Do lower exclusion rates mean improved behaviour? Or do they instead indicate higher tolerance levels of bad behaviour, or indeed better on-site school provision for the behaviourally challenged? It would be advisable to look for other sources of evidence, too. If you have an on-call ‘duty’ system like we do, could you collect data on how often senior staff are called to incidents of poor behaviour? Or could you survey the students on a termly basis by asking ‘how many times were your lessons disrupted by bad behaviour yesterday?’? Even better – do both. To avoid the availability bias, therefore, we need to find our answers in a wider base of evidence – and preferably evidence from a range of sources.
2. Self-serving bias is the way we tend to attribute our successes to ourselves and our failures to external factors beyond our control.
Never is the self-serving bias more evident in schools than on exam results day. Let’s take two hypothetical students, Dan and Tom, to exemplify this phenomenon. Now Dan and Tom were in my GCSE class and were statistically similar: white, working-class, with lower than average attendance and below average prior attainment. However, there was one difference on that August afternoon: Dan achieved an E in English, Tom got a B.
How do I attribute these differences? Well, Dan was hardly ever at school, and he arrived in year 7 with a level 3 KS3 score and, to be honest, white working-class boys achieved terribly nationally anyway. As for Tom? Well (!), we built up a great relationship right from the start, he seemed to find my lessons particularly engaging and I did spend an awful lot of time giving my students careful feedback. In other words: I have blamed Dan’s failure on external factors and accredited Tom’s success to the enduring prowess of my classroom practice. The self-serving bias caught red-handed.
Although the self-serving bias is natural (and, to some extent, provides us with a useful self-protecting mechanism), the education system currently incentivises such disregard for objective truth. If you want honest accounts of success and failure then you first need to remove data targets and performance-related pay. Even if we discount out-of-school factors (genetics and family background), there are a huge number of in-school factors outside the control of the average classroom teacher that influence both good and bad final exam results: curriculum design, choice of exam board, subject timetabling, class profile, how subject knowledge and skills are reinforced by the whole-school curriculum, how much progress the child made with KS3 teachers…the list is endless. To truly begin to understand the complex ways students succeed or fail we need to see the teacher’s contribution for what it is – one part of a much bigger picture. Once we take this rational view, we can begin building up an evidence base – perhaps through long-term case studies – that might help us to better understand the interaction between the complex variables we work with.
3. The regression to the mean delusion is a common fallacy. If a variable is extreme on its first measurement, it is likely to be much closer to average the second time it is measured.
Let’s use behaviour in class as an example. Imagine one Tuesday your class are particularly badly behaved – the worst you have seen them. The next lesson you try something different: perhaps a more engaging starter, or a new seating plan, or bawling at them like a sergeant major or threatening them all with a lunch-time detention. That lesson the class are better behaved, so you believe your newly adopted strategy to be an out-and-out success.
Now perhaps it really was an out-and-out success in its own right, but the improvement in the class’ behaviour may only have been a regression to the mean. When you have witnessed extreme, beyond-the-ordinary behaviour from a class, it is statistically more likely that behaviour will be better the next lesson – i.e they return back towards the norm. In the same way, if a problematic class are better behaved than usual for one lesson, be prepared for them to return back to their old tricks in the subsequent one. In both cases, they have regressed to the mean.
The takeaway here – applicable to all strategies and interventions undertaken in a school – is to be careful not to jump to assumptions too quickly. When you witness extremes of success or failure out of kilter with the norm, be vigilant not to immediately attribute this to the intervention itself. Until you have more robust evidence, be careful not to jump to conclusions too quickly. Try out the intervention a few more times and if you do choose to share it with colleagues before you have strong evidence, do so tentatively.
There are many, many more biases worth knowing about – I cannot share them all here. What is most critical, however, is that we question, test and evaluate our assumptions and intuitions, whatever our position in the educational system – from trainee teacher to Secretary of State. Unless the evidence is incontrovertible (and it almost never is) always avoid the simplistic answer, however seductive it sounds.
So, does this mean that we should adopt a nihilistic, iconoclastic standpoint, always seeking to pour scorn on tradition or the latest initiative (or both)? Absolutely not. A few things work very well in education; many work partially well; some do not work at all. Sometimes our intuitions are absolutely right, sometimes they are not. We should not embrace uncertainty, but instead accept it as the starting point on a journey that might lead us towards greater certainty. More robust judgements and decisions allow us to tweak and modify our actions more confidently. However, these are only possible in a climate of enquiry, honesty and humility. The system has a lot to do until we reach that point.