I think that they both agree that “decision” here means “choice to embark on a course of action other than the null action”, where the null action may be simply waiting for more data. Where they disagree is the relative costs of the null action versus a member of a set of poorly known actions; it seems that the second speaker is trying to remind the first that the null action carries a cost, whether in opportunity or otherwise.
I think that they both agree that “decision” here means “choice to embark on a course of action other than the null action”, where the null action may be simply waiting for more data. Where they disagree is the relative costs of the null action versus a member of a set of poorly known actions; it seems that the second speaker is trying to remind the first that the null action carries a cost, whether in opportunity or otherwise.