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Time inconsistency and mountaineering

It has been a bad season for the mountain rescue teams in Scotland - another avalanche yesterday, coming just days after a student from Leeds University died. I know nothing about these individual cases so would not want to comment on them. But, they are a reminder that the most important skill in mountaineering is not reading a map, using an ice axe, or knowing how to tie onto a rope - it is knowing when to ditch plan A and go onto plans B, C and D. The human propensity for time-inconsistency, however, makes this a surprisingly difficult skill too master.
   For example, I remember many years ago attempting a quick trip up Snowdon in Wales. I'd been marking essays or something and needed some respite. It was a gnarly day - the wind was very strong, visibility poor, snow, ice etc. I met a mountain guide half way up with a few clients and he confidently predicted that no one was getting to the top today. I carried on and got within 200m of the top before finally turning back. This example comes to mind as powerful reminder of the difficulties of being time-consistent. I have climbed Snowdon many, many times, and had already had a great day out on the mountain - there was nothing at all I would gain from walking that extra 200m - the optimal decision was obvious - yet the desire to go on was so strong. That desire is what behavioral economists call present bias. A bias that means the 'short-term self' can make a decision the 'long-term self' would not have made.
   Another example springs to mind. This time in the French Alps where I needed to cross an avalanche prone slope. On this occasion it was an absolutely beautiful day, but the sunlight was only going to increase the chances of the slope crashing down around me. I got 50m across the slope before sense prevailed and I retraced my steps. I mention this example because I remember standing on the slope, seemingly in slow motion, as one part of my brain did battle with another on the merits of continuing across the slope. Again, in the cold light of day - the decision is obvious - the slope was too dangerous. But the desire to go on was strong.
    Whether they know it or not experienced mountaineers are well aware of time-inconsistency. They will have a series of mental tricks that they use to overcome present bias. The most common trick, for example, is to set a cut-off time at which to turn around no matter what. Experience is the key thing here. With experience, people can learn to control present bias. For example, the good student might have mental tricks to make sure homework is not left until the last minute. Someone on a diet can have tricks to avoid eating chocolate. And someone who has quit smoking might have tricks to avoid the urge to smoke. Present bias is more of a problem when people are inexperienced, saving for retirement being the classic example. We only retire once, and then its too late to realise that we should have saved more while we could.
   What I find most thought proviking, however, about recent tragedies in the Scottish mountains is that they have involved groups of people. Behavioral economics is now pretty good at understanding an individual's decision. But, we are still woefully unaware of how group decisions compare to individual decisions. Are a group of people able to avoid the present bias of individual group members? Or, can the present bias of one group member infect others? We have no idea what the answer to these questions are. That seems like an intruiging challenge for future research. 
  



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