The following article was published on 05 July 2018 on <link https: science.orf.at stories external-link-new-window external link in new>science.orf.at:

What does climate change have to do with dirty dishes in the office kitchen? In both cases, cooperation between people breaks down: a new model explains why this is — and how things could be done differently.

Game-theoretic approaches for exploring how cooperation emerges are nothing new in themselves — but a team led by Christian Hilbe (IST Austria) and Martin Nowak (Harvard University) has turned previous research into "special cases" of their new model.

For the first time in their model, the state of the resource in question changes depending on how heavily the players have drawn on it in the previous round. The researchers argue that this makes the new model much closer to reality than its predecessors.

The resource can be almost anything: an overexploited forest, for instance; or the atmosphere, whose temperature stability is increasingly threatened by industry and transport; or even an office kitchen where dirty dishes pile up because nobody feels responsible for tidying up.

Negative consequences curb selfishness

The model by Hilbe and Nowak incorporates the following rule: a player who does not cooperate is effectively demoted and must play for a lower-value stake in the next round. Whoever does not exploit the resources selfishly, but instead takes only a sustainable yield from the pool, moves up and can win even more in the next round. In reality, this would correspond roughly to an overexploited forest or depleted soil yielding less the following year than one that has been managed sustainably.

Thanks to this mechanism, players' willingness to cooperate increased significantly compared to models with a static resource, the researchers reported. The most conducive condition for resource-conserving collaboration was when participants received rapid negative feedback in the form of dramatically reduced yields. The new model now makes it possible to examine much more effectively how to create an environment that encourages people to work together, Hilbe explains in a press release.

When it comes to climate change, however, this insight is only of limited help: the consequences of CO2 emissions are lasting, but they manifest with a time delay. The "negative feedback" modelled by the researchers may not arrive quickly enough in this case.