The Complexity of Multiwinner Voting Rules with Variable Number of Winners

نویسندگان

  • Piotr Faliszewski
  • Arkadii M. Slinko
  • Nimrod Talmon
چکیده

We consider the approval-based model of elections, and undertake a computational study of voting rules which select committees whose size is not predetermined. While voting rules that output committees with a predetermined number of winning candidates are quite well studied, the study of elections with variable number of winners has only recently been initiated by Kilgour [18]. This paper aims at achieving a better understanding of these rules, their computational complexity, and on scenarios for which they might be applicable.

برای دانلود متن کامل این مقاله و بیش از 32 میلیون مقاله دیگر ابتدا ثبت نام کنید

ثبت نام

اگر عضو سایت هستید لطفا وارد حساب کاربری خود شوید

منابع مشابه

Properties of multiwinner voting rules

The goal of this paper is to propose and study properties of multiwinner voting rules (with a particular focus on rules based in some way on single-winner scoring rules). We consider, e.g., SNTV, Bloc, k-Borda, STV, and several variants of Chamberlin–Courant’s and Monroe’s rules, identify two natural approaches to defining multiwinner rules, and show that many of our rules can be captured by on...

متن کامل

Multiwinner Analogues of the Plurality Rule: Axiomatic and Algorithmic Perspectives

We characterize the class of committee scoring rules that satisfy the fixed-majority criterion. In some sense, the committee scoring rules in this class are multiwinner analogues of the single-winner Plurality rule, which is uniquely characterized as the only single-winner scoring rule that satisfies the simple majority criterion. We find that, for most of the rules in our new class, the comple...

متن کامل

Complexity of Strategic Behavior in Multi-Winner Elections

Although recent years have seen a surge of interest in the computational aspects of social choice, no specific attention has previously been devoted to elections with multiple winners, e.g., elections of an assembly or committee. In this paper, we characterize the worst-case complexity of manipulation and control in the context of four prominent multiwinner voting systems, under different formu...

متن کامل

Complexity of Shift Bribery in Committee Elections

We study the (parameterized) complexity of SHIFT BRIBERY for multiwinner voting rules. We focus on the SNTV, Bloc, k-Borda, and Chamberlin-Courant, as well as on approximate variants of the Chamberlin-Courant rule, since the original rule is NP-hard to compute. We show that SHIFT BRIBERY tends to be significantly harder in the multiwinner setting than in the single-winner one by showing setting...

متن کامل

Robustness Among Multiwinner Voting Rules

We investigate how robust are results of committee elections to small changes in the input preference orders, depending on the voting rules used. We find that for typical rules the effect of making a single swap of adjacent candidates in a single preference order is either that (1) at most one committee member can be replaced, or (2) it is possible that the whole committee can be replaced. We a...

متن کامل

ذخیره در منابع من


  با ذخیره ی این منبع در منابع من، دسترسی به آن را برای استفاده های بعدی آسان تر کنید

برای دانلود متن کامل این مقاله و بیش از 32 میلیون مقاله دیگر ابتدا ثبت نام کنید

ثبت نام

اگر عضو سایت هستید لطفا وارد حساب کاربری خود شوید

عنوان ژورنال:
  • CoRR

دوره abs/1711.06641  شماره 

صفحات  -

تاریخ انتشار 2017