Fine-Grained Complexity and Algorithms for the Schulze Voting Method*
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A Treasury System for Cryptocurrencies: Enabling Better Collaborative Intelligence ⋆
A Treasury System for Cryptocurrencies: Enabling Better Collaborative Intelligence ? Bingsheng Zhang1, Roman Oliynykov2, and Hamed Balogun3 1 Lancaster University, UK [email protected] 2 Input Output Hong Kong Ltd. [email protected] 3 Lancaster University, UK [email protected] Abstract. A treasury system is a community controlled and decentralized collaborative decision- making mechanism for sustainable funding of the blockchain development and maintenance. During each treasury period, project proposals are submitted, discussed, and voted for; top-ranked projects are funded from the treasury. The Dash governance system is a real-world example of such kind of systems. In this work, we, for the first time, provide a rigorous study of the treasury system. We modelled, designed, and implemented a provably secure treasury system that is compatible with most existing blockchain infrastructures, such as Bitcoin, Ethereum, etc. More specifically, the proposed treasury system supports liquid democracy/delegative voting for better collaborative intelligence. Namely, the stake holders can either vote directly on the proposed projects or delegate their votes to experts. Its core component is a distributed universally composable secure end-to-end verifiable voting protocol. The integrity of the treasury voting decisions is guaranteed even when all the voting committee members are corrupted. To further improve efficiency, we proposed the world's first honest verifier zero-knowledge proof for unit vector encryption with logarithmic size communication. This partial result may be of independent interest to other cryptographic protocols. A pilot system is implemented in Scala over the Scorex 2.0 framework, and its benchmark results indicate that the proposed system can support tens of thousands of treasury participants with high efficiency. -
Mohanoor Ou 0169D 10067.Pdf (1.725Mb)
UNIVERSITY OF OKLAHOMA GRADUATE COLLEGE DATA GATHERING TECHNIQUES ON WIRELESS SENSOR NETWORKS A DISSERTATION SUBMITTED TO THE GRADUATE FACULTY in partial fulfillment of the requirements for the Degree of DOCTOR OF PHILOSOPHY By ARAVIND MOHANOOR Norman, Oklahoma 2008 DATA GATHERING TECHNIQUES ON WIRELESS SENSOR NETWORKS A DISSERTATION APPROVED FOR THE SCHOOL OF COMPUTER SCIENCE BY _____________________________________ Dr. Sridhar Radhakrishnan, Chair _____________________________________ Dr. S. Lakshmivarahan _____________________________________ Dr. Sudarshan Dhall _____________________________________ Dr. John Antonio _____________________________________ Dr. Marilyn Breen © Copyright by ARAVIND MOHANOOR 2008 All Rights Reserved Acknowledgments I wish to express my sincere gratitude to my dissertation advisor Dr. Sridhar Radhakrishnan for his guidance and inspiration without which this work would have been impossible. His constant enthusiasm and support was a big factor in my persisting through the many peaks and troughs which are commonplace during graduate studies. It is fair to say that I learnt much from him about research as well as life. I would like to express my gratitude to my committee members Dr. S. Lakshmivarahan, Dr. Sudarshan Dhall, Dr. John Antonio and Dr. Marilyn Breen for serving on my dissertation committee. I would also like to thank Dr. Venkatesh Sarangan of Oklahoma State University for many interesting discussions about research and for helping me introduce rigor to my approach to research writing. I would like to express many thanks to Dr. Henry Neeman for a very stimulating and enjoyable experience as a Teaching Assistant for CS 1313. I would also like to express thanks to Dr. Shivakumar Raman for the financial support during the last year of my doctoral studies. -
Game Theory and Democracy Homework Problems
Game Theory and Democracy Homework Problems PAGE 82 Challenge Problem: Show that any voting model (such as the Unit Interval Model or the Unit Square Model) which has a point symmetry always has a Condorcet winner for every election, namely the candidate who is closest to the point of symmetry! PAGE 93 Exercise: Show that if there are not any cycles of any length in the preferences of the voters, then there must be a Condorcet winner. (Don’t worry about making your proof rigorous, just convince yourself of this fact, to the point you could clearly explain your ideas to someone else.) PAGE 105 Exercise: Prove that the strongest chain strength of a chain from Candidate Y to Candidate X is 3. (If you can convince a skeptical friend that it is true, then that is a proof.) Exercise: Prove that it is never necessary to use a candidate more than once to find a chain with the strongest chain strength between two candidates. Hint: Show that whenever there is a loop, like the one shown in red Y (7) Z (3) W (9) Y (7) Z (3) W (11) X, we can consider a shortened chain by simply deleting the red loop Y (7) Z (3) W (11) X which is at least as strong as the original loop. Exercises: Prove that all of the chains above are in fact strongest chains, as claimed. Hint: The next figure, which has all of the information of the margin of victory matrix, will be useful, and is the type of figure you may choose to draw for yourself for other elections, from time to time. -
Acyclic Graphs, Trees and Spanning Trees
Acyclic graphs, trees and spanning trees Stanislav Pal´uch Fakulta riadenia a informatiky, Zilinsk´auniverzitaˇ 20. apr´ıla 2016 Stanislav Pal´uch, Fakulta riadenia a informatiky, Zilinsk´auniverzitaˇ Acyclic graphs, trees and spanning trees 1/21 Opakovanie – Cyklus Definition Cycle (directed cycle, quasi-cycle) is non trivial closed walk (directed walk, quasi-walk) in which every vertex but the first and the last appears at most once. Stanislav Pal´uch, Fakulta riadenia a informatiky, Zilinsk´auniverzitaˇ Acyclic graphs, trees and spanning trees 2/21 Acyklic graph and tree Definition An acyclic graph is a graph that has no cycles. Definition A tree is a connected acyclic graph. Remark Trivial graph is a tree. Remark Every component of an acyclic graph is a tree (is connected and dous not contain a cycle). Hence an acyclic graph can be considered as several trees. That is why the term forest is often used as a synonym for acyclic graph“. ” Stanislav Pal´uch, Fakulta riadenia a informatiky, Zilinsk´auniverzitaˇ Acyclic graphs, trees and spanning trees 3/21 Acyklic graph and tree Definition An acyclic graph is a graph that has no cycles. Definition A tree is a connected acyclic graph. Remark Trivial graph is a tree. Remark Every component of an acyclic graph is a tree (is connected and dous not contain a cycle). Hence an acyclic graph can be considered as several trees. That is why the term forest is often used as a synonym for acyclic graph“. ” Stanislav Pal´uch, Fakulta riadenia a informatiky, Zilinsk´auniverzitaˇ Acyclic graphs, trees and spanning trees 3/21 Acyklic graph and tree Definition An acyclic graph is a graph that has no cycles. -
Computational Perspectives on Democracy
Computational Perspectives on Democracy Anson Kahng CMU-CS-21-126 August 2021 Computer Science Department School of Computer Science Carnegie Mellon University Pittsburgh, PA 15213 Thesis Committee: Ariel Procaccia (Chair) Chinmay Kulkarni Nihar Shah Vincent Conitzer (Duke University) David Pennock (Rutgers University) Submitted in partial fulfillment of the requirements for the degree of Doctor of Philosophy. Copyright c 2021 Anson Kahng This research was sponsored by the National Science Foundation under grant numbers IIS-1350598, CCF- 1525932, and IIS-1714140, the Department of Defense under grant number W911NF1320045, the Office of Naval Research under grant number N000141712428, and the JP Morgan Research grant. The views and conclusions contained in this document are those of the author and should not be interpreted as representing the official policies, either expressed or implied, of any sponsoring institution, the U.S. government or any other entity. Keywords: Computational Social Choice, Theoretical Computer Science, Artificial Intelligence For Grandpa and Harabeoji. iv Abstract Democracy is a natural approach to large-scale decision-making that allows people affected by a potential decision to provide input about the outcome. However, modern implementations of democracy are based on outdated infor- mation technology and must adapt to the changing technological landscape. This thesis explores the relationship between computer science and democracy, which is, crucially, a two-way street—just as principles from computer science can be used to analyze and design democratic paradigms, ideas from democracy can be used to solve hard problems in computer science. Question 1: What can computer science do for democracy? To explore this first question, we examine the theoretical foundations of three democratic paradigms: liquid democracy, participatory budgeting, and multiwinner elections. -
An Optimal Single-Winner Preferential Voting System Based on Game Theory∗
An Optimal Single-Winner Preferential Voting System Based on Game Theory∗ Ronald L. Rivest and Emily Shen Abstract • The election winner is determined by a random- ized method, based for example on the use of We present an optimal single-winner preferential vot- ten-sided dice, that picks outcome x with prob- ing system, called the \GT method" because of its in- ability p∗(x). If there is a Condorcet winner x, teresting use of symmetric two-person zero-sum game then p∗(x) = 1, and no dice are needed. We theory to determine the winner. Game theory is not also briefly discuss a deterministic variant of GT, used to describe voting as a multi-player game be- which we call GTD. tween voters, but rather to define when one voting system is better than another one. The cast ballots The GT system, essentially by definition, is opti- determine the payoff matrix, and optimal play corre- mal: no other voting system can produce election sponds to picking winners optimally. outcomes that are liked better by the voters, on the The GT method is quite simple and elegant, and average, than those of the GT system. We also look works as follows: at whether the GT system has several standard prop- erties, such as monotonicity, consistency, etc. • Voters cast ballots listing their rank-order pref- The GT system is not only theoretically interest- erences of the alternatives. ing and optimal, but simple to use in practice; it is probably easier to implement than, say, IRV. We feel • The margin matrix M is computed so that for that it can be recommended for practical use. -
Instructor's Manual
The Mathematics of Voting and Elections: A Hands-On Approach Instructor’s Manual Jonathan K. Hodge Grand Valley State University January 6, 2011 Contents Preface ix 1 What’s So Good about Majority Rule? 1 Chapter Summary . 1 Learning Objectives . 2 Teaching Notes . 2 Reading Quiz Questions . 3 Questions for Class Discussion . 6 Discussion of Selected Questions . 7 Supplementary Questions . 10 2 Perot, Nader, and Other Inconveniences 13 Chapter Summary . 13 Learning Objectives . 14 Teaching Notes . 14 Reading Quiz Questions . 15 Questions for Class Discussion . 17 Discussion of Selected Questions . 18 Supplementary Questions . 21 3 Back into the Ring 23 Chapter Summary . 23 Learning Objectives . 24 Teaching Notes . 24 v vi CONTENTS Reading Quiz Questions . 25 Questions for Class Discussion . 27 Discussion of Selected Questions . 29 Supplementary Questions . 36 Appendix A: Why Sequential Pairwise Voting Is Monotone, and Instant Runoff Is Not . 37 4 Trouble in Democracy 39 Chapter Summary . 39 Typographical Error . 40 Learning Objectives . 40 Teaching Notes . 40 Reading Quiz Questions . 41 Questions for Class Discussion . 42 Discussion of Selected Questions . 43 Supplementary Questions . 49 5 Explaining the Impossible 51 Chapter Summary . 51 Error in Question 5.26 . 52 Learning Objectives . 52 Teaching Notes . 53 Reading Quiz Questions . 54 Questions for Class Discussion . 54 Discussion of Selected Questions . 55 Supplementary Questions . 59 6 One Person, One Vote? 61 Chapter Summary . 61 Learning Objectives . 62 Teaching Notes . 62 Reading Quiz Questions . 63 Questions for Class Discussion . 65 Discussion of Selected Questions . 65 CONTENTS vii Supplementary Questions . 71 7 Calculating Corruption 73 Chapter Summary . 73 Learning Objectives . 73 Teaching Notes . -
Selecting the Runoff Pair
Selecting the runoff pair James Green-Armytage New Jersey State Treasury Trenton, NJ 08625 [email protected] T. Nicolaus Tideman Department of Economics, Virginia Polytechnic Institute and State University Blacksburg, VA 24061 [email protected] This version: May 9, 2019 Accepted for publication in Public Choice on May 27, 2019 Abstract: Although two-round voting procedures are common, the theoretical voting literature rarely discusses any such rules beyond the traditional plurality runoff rule. Therefore, using four criteria in conjunction with two data-generating processes, we define and evaluate nine “runoff pair selection rules” that comprise two rounds of voting, two candidates in the second round, and a single final winner. The four criteria are: social utility from the expected runoff winner (UEW), social utility from the expected runoff loser (UEL), representativeness of the runoff pair (Rep), and resistance to strategy (RS). We examine three rules from each of three categories: plurality rules, utilitarian rules and Condorcet rules. We find that the utilitarian rules provide relatively high UEW and UEL, but low Rep and RS. Conversely, the plurality rules provide high Rep and RS, but low UEW and UEL. Finally, the Condorcet rules provide high UEW, high RS, and a combination of UEL and Rep that depends which Condorcet rule is used. JEL Classification Codes: D71, D72 Keywords: Runoff election, two-round system, Condorcet, Hare, Borda, approval voting, single transferable vote, CPO-STV. We are grateful to those who commented on an earlier draft of this paper at the 2018 Public Choice Society conference. 2 1. Introduction Voting theory is concerned primarily with evaluating rules for choosing a single winner, based on a single round of voting. -
Chapter 3 Voting Systems
Chapter 3 Voting Systems 3.1 Introduction We rank everything. We rank movies, bands, songs, racing cars, politicians, professors, sports teams, the plays of the day. We want to know “who’s number one?” and who isn't. As a lo- cal sports writer put it, “Rankings don't mean anything. Coaches continually stress that fact. They're right, of course, but nobody listens. You know why, don't you? People love polls. They absolutely love ’em” (Woodling, December 24, 2004, p. 3C). Some rankings are just for fun, but people at the top sometimes stand to make a lot of money. A study of films released in the late 1970s and 1980s found that, if a film is one of the 5 finalists for the Best Picture Oscar at the Academy Awards, the publicity generated (on average) generates about $5.5 mil- lion in additional box office revenue. Winners make, on average, $14.7 million in additional revenue (Nelson et al., 2001). In today's inflated dollars, the figures would no doubt be higher. Actors and directors who are nominated (and who win) should expect to reap rewards as well, since the producers of new films are eager to hire Oscar-winners. This chapter is about the procedures that are used to decide who wins and who loses. De- veloping a ranking can be a tricky business. Political scientists have, for centuries, wrestled with the problem of collecting votes and moulding an overall ranking. To the surprise of un- 1 CHAPTER 3. VOTING SYSTEMS 2 dergraduate students in both mathematics and political science, mathematical concepts are at the forefront in the political analysis of voting procedures. -
Math in Society
Math in Society Edition 1.1 Revision 3 Contents Voting Theory . 1 David Lippman Weighted Voting . 19 David Lippman Fair Division . 31 David Lippman Graph Theory . 49 David Lippman Scheduling . 79 David Lippman Growth Models . 95 David Lippman Finance . 111 David Lippman Statistics . 131 David Lippman, Jeff Eldridge, onlinestatbook.com Describing Data . 143 David Lippman, Jeff Eldridge, onlinestatbook.com Historical Counting Systems . 167 Lawrence Morales Solutions to Selected Exercises . 201 David Lippman Pierce College Ft Steilacoom Copyright © 2010 David Lippman This book was edited by David Lippman, Pierce College Ft Steilacoom Development of this book was supported, in part, by the Transition Math Project Statistics and Describing Data contain portions derived from works by: Jeff Eldridge, Edmonds Community College (used under CC-BY-SA license) www.onlinestatbook.com (used under public domain declaration) Historical Counting Systems derived from work by: Lawrence Morales, Seattle Central Community College (used under CC-BY-SA license) Front cover photo: Jan Tik, http://www.flickr.com/photos/jantik/, CC-BY 2.0 This text is licensed under a Creative Commons Attribution-Share Alike 3.0 United States License. To view a copy of this license, visit http://creativecommons.org/licenses/by-sa/3.0/us/ or send a letter to Creative Commons, 171 Second Street, Suite 300, San Francisco, California, 94105, USA. You are free: to Share — to copy, distribute, display, and perform the work to Remix — to make derivative works Under the following conditions: Attribution. You must attribute the work in the manner specified by the author or licensor (but not in any way that suggests that they endorse you or your use of the work). -
How to Enhance Democracy?
What is democracy? Towards a global democracy Democratic allocation of money Original voting systems E-democracy References How to enhance democracy? Adrien Fabre Paris School of Economics 11/2015 Adrien Fabre How to enhance democracy? What is democracy? Towards a global democracy Democratic allocation of money Original voting systems E-democracy References Contents 1 What is democracy? 2 Towards a global democracy 3 Democratic allocation of money 4 Original voting systems 5 E-democracy Adrien Fabre How to enhance democracy? What is democracy? Towards a global democracy Democratic allocation of money Original voting systems E-democracy References Denitions Democracy is a political regime such that : - the necessary conditions for well-being are insured for all - each person has the same power of decision on issues that matter for them, where the necessary conditions for well-being are the ability to have access to: - drinkable water, food, health-care - a healthy environment, security, housing - attention, an education, information Adrien Fabre How to enhance democracy? What is democracy? Towards a global democracy Subsidiarity Democratic allocation of money Some insights for a global governance Original voting systems What could a global governance enact? E-democracy References Denition Subsidiarity is the idea that a central authority should have a subsidiary function, performing only those tasks which cannot be performed eectively at a more immediate or local level. Subsidiarity principle reveals us that some stakes must be decided at the international scale, notably: ght and adaptation to the climate change regulation of nancial markets and the monetary system allocation of non renewable resources ght of poverty Adrien Fabre How to enhance democracy? What is democracy? Towards a global democracy Subsidiarity Democratic allocation of money Some insights for a global governance Original voting systems What could a global governance enact? E-democracy References A global governance should be inclusive, i.e. -
Minimax Is the Best Electoral System After All
1 Minimax Is the Best Electoral System After All Richard B. Darlington Department of Psychology, Cornell University Abstract When each voter rates or ranks several candidates for a single office, a strong Condorcet winner (SCW) is one who beats all others in two-way races. Among 21 electoral systems examined, 18 will sometimes make candidate X the winner even if thousands of voters would need to change their votes to make X a SCW while another candidate Y could become a SCW with only one such change. Analysis supports the intuitive conclusion that these 18 systems are unacceptable. The well-known minimax system survives this test. It fails 10 others, but there are good reasons to ignore all 10. Minimax-T adds a new tie-breaker. It surpasses competing systems on a combination of simplicity, transparency, voter privacy, input flexibility, resistance to strategic voting, and rarity of ties. It allows write-ins, machine counting except for write-ins, voters who don’t rate or rank every candidate, and tied ratings or ranks. Eleven computer simulation studies used 6 different definitions (one at a time) of the “best” candidate, and found that minimax-T always soundly beat all other tested systems at picking that candidate. A new maximum-likelihood electoral system named CMO is the theoretically optimum system under reasonable conditions, but is too complex for use in real-world elections. In computer simulations, minimax and minimax-T nearly always pick the same winners as CMO. Comments invited [email protected] Copyright Richard B. Darlington May be distributed free for non-commercial purposes 2 1.