Incomplete Preferences in Single-Peaked Electorates
نویسنده
چکیده
Incomplete preferences are likely to arise in realworld preference aggregation and voting systems. This paper deals with determining whether an incomplete preference profile is single-peaked. This is essential information since many intractable voting problems become tractable for single-peaked profiles. We prove that for incomplete profiles the problem of determining single-peakedness is NPcomplete. Despite this computational hardness result, we find two polynomial-time algorithms for reasonably restricted settings.
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