Yang observes that earlier methods considered dominance paths that often go in circles with the same coalitions blocking repeatedly. z-dominance targets a core element z, but also respects the history of the negotiations in the sense that earlier blocking coalitions are not made worse off. Yang does not prove that z-dominating sequences exist from each imputation, but refers to Sengupta and Sengupta (1996) for a proof. All z-dominating sequences end in the core and since a coalition may block at most once in such a sequence, their length is smaller than the number of active coalitions.
(Review written for Mathematical Reviews.)
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