Modeling the Ellsberg Paradox by Argument Strength
This provides a new model for a specific paradox in decision theory, but it is incremental as it builds on existing ideas about argument strength.
The authors tackled the problem of modeling the Ellsberg paradox by proposing a formal measure of argument strength based on probability and precision, and they found that this measure predicts human inferences in experiments with 60 participants.
We present a formal measure of argument strength, which combines the ideas that conclusions of strong arguments are (i) highly probable and (ii) their uncertainty is relatively precise. Likewise, arguments are weak when their conclusion probability is low or when it is highly imprecise. We show how the proposed measure provides a new model of the Ellsberg paradox. Moreover, we further substantiate the psychological plausibility of our approach by an experiment (N = 60). The data show that the proposed measure predicts human inferences in the original Ellsberg task and in corresponding argument strength tasks. Finally, we report qualitative data taken from structured interviews on folk psychological conceptions on what argument strength means.