Andreas Glöckner

Who they are

Glöckner publishes in judgement and decision-making. This page covers the paper that matters to the decision fatigue debate, "The irrational hungry judge effect revisited: Simulations reveal that the magnitude of the effect is overestimated", in volume 11, issue 6 of Judgment and Decision Making (2016, pages 601 to 610). No affiliation is confirmed for this page, so none is given.

The paper takes the 2011 parole study seriously. It notes that the reported effect was large, with an odds ratio of about 35, more than twice the size usually counted as large. It then asks what a rational judge would produce. Favourable cases took longer than unfavourable ones, on average 7.37 minutes against 5.21. A judge who ends a session rather than start a case likely to run long would see favourable rulings thin out towards the end. In the simulations such a judge produced a decline comparable to the reported one, though somewhat smaller, and censoring the last 5 per cent of cases in each session added to it.

Glöckner also summarises the earlier exchange in which Keren Weinshall-Margel and John Shapard questioned case order and Danziger and colleagues replied. He allows that some of the original pattern remains unexplained by his artefact, and he recommends simulation as a way to look for rational explanations of apparently irrational behaviour.

What the record shows

Glöckner's 2016 paper in Judgment and Decision Making revisits the parole study by Danziger and colleagues. Its abstract notes that the original authors cautiously speculated that mental depletion might drive the effect. A simulation showed that the observed influence of order can be explained as a statistical artefact of favourable rulings taking longer than unfavourable ones, and that a hypothetical rational judge who plans ahead minimally and ends a session instead of starting cases assumed to take longer would produce an effect of similar magnitude. One methodological detail increased the artefact and produced it even without foresight.

In the full text, favourable rulings averaged 7.37 minutes (standard deviation 5.11) and unfavourable ones 5.21 minutes (4.97), the simulated effects were somewhat smaller than the original ones, and further factors may have contributed. The paper recommends wider use of simulations to identify non-obvious rational explanations.

Key papers

Glöckner, A. (2016). The irrational hungry judge effect revisited: Simulations reveal that the magnitude of the effect is overestimated. Judgment and Decision Making, 11(6), 601-610. No books are listed for this author on this page.

Key ideas

A downward trend in favourable rulings can arise from session planning alone, with no fatigue.

The original hungry judge effect was likely overestimated, though not shown to be zero.

Simulation is a useful check on explanations that treat behaviour as irrational.

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