Computing the Margin of Victory in Preferential Parliamentary Elections

We show how to use automated computation of election margins to assess the number of votes that would need to change in order to alter a parliamentary outcome for single-member preferential electorates. In the context of increasing automation of Australian electoral processes, and accusations of deliberate interference in elections in Europe and the USA, this work forms the basis of a rigorous statistical audit of the parliamentary election outcome. Our example is the New South Wales Legislative Council election of 2015, but the same process could be used for any similar parliament for which data was available, such as the Australian House of Representatives given the proposed automatic scanning of ballots

An Introduction to Voting Rule Verification

We give an introduction to deductive verification methods that can be used to formally prove that voting rules and their implementations satisfy specified properties and conform to the desired democratic principles. In the first part of the paper we explain the basic principles: We describe how first-order logic with theories can be used to formalise the desired properties. We explain the difference between (1) proving that one set of properties implies another property, (2) proving that a voting rule implementation has a certain property, and (3) proving that a voting rule implementation is a refinement of an executable specification. And we explain the different technologies: (1) SMT-based testing, (2) bounded program verification, (3) relational program verification, and (4) symmetry breaking. In this first part of the paper, we also explain the difference between verifying functional and relational properties (such as symmetries). In the second part, we present case studies, including (1) the specification and verification of semantic properties for an STV rule used for electing the board of trustees for a major international conference and (2) the deduction-based computation of election margins for the Danish national parliamentary elections

Adaptively Weighted Audits of Instant-Runoff Voting Elections: AWAIRE

An election audit is risk-limiting if the audit limits (to a pre-specified threshold) the chance that an erroneous electoral outcome will be certified. Extant methods for auditing instant-runoff voting (IRV) elections are either not risk-limiting or require cast vote records (CVRs), the voting system's electronic record of the votes on each ballot. CVRs are not always available, for instance, in jurisdictions that tabulate IRV contests manually. We develop an RLA method (AWAIRE) that uses adaptively weighted averages of test supermartingales to efficiently audit IRV elections when CVRs are not available. The adaptive weighting 'learns' an efficient set of hypotheses to test to confirm the election outcome. When accurate CVRs are available, AWAIRE can use them to increase the efficiency to match the performance of existing methods that require CVRs. We provide an open-source prototype implementation that can handle elections with up to six candidates. Simulations using data from real elections show that AWAIRE is likely to be efficient in practice. We discuss how to extend the computational approach to handle elections with more candidates. Adaptively weighted averages of test supermartingales are a general tool, useful beyond election audits to test collections of hypotheses sequentially while rigorously controlling the familywise error rate.Comment: 16 pages, 3 figures, accepted for E-Vote-ID 202

Corporate Taxation and the Impact of Governance, Political and Economic Factors

In this paper we first use two international data sets to investigate how governance, political and economic factors influence corporate tax rates. We show that institutional and political factors matter: good governance reduces the tax rate; a parliamentary system, especially a plurality election system, and religious or nationalist executives too, push tax rates upward. Traditional variables also matter: economic openness has a negative effect on tax rates although market size has a positive one. Though it is not robust, interaction among neighbors also plays a role. Then we turn to theory and extend a standard model of tax competition to provide a channel for the elements set forth so far to influence tax rates formation; nested in the economic theory of lobbying that exercise provides our empirical investigation with theoretical foundations.institutions and taxation, tax competition, lobbying

Towards a New Ontology of Polling Inaccuracy: The Benefits of Conceiving of Elections as Heterogenous Phenomena for the Study of Pre-election Polling Error

A puzzle exists at the heart of pre-election polling. Despite continual methodological improvement and repeated attempts to identify and correct issues laid bare by misprediction, average polling accuracy has not notably improved since the conclusion of the Second World War. In this thesis, I contend that this is the result of a poll-level focus within the study of polling error that is both incommensurate with its evolution over time and the nature of the elections that polls seek to predict. I hold that differences between elections stand as a plausible source of polling error and situate them within a novel four-level model of sources of polling error. By establishing the heterogenous nature of elections as phenomena and its expected impact on polling error, I propose a new election-level ontology through which the inaccuracy of polls can be understood. I test the empirical validity of this new ontology by using a novel multi-level model to analyse error across the most expansive polling dataset assembled to date, encompassing 11,832 in-campaign polls conducted in 497 elections across 83 countries, finding that membership within different elections meaningfully impacts polling error variation. With the empirical validity of my proposed ontology established, I engage in an exploratory analysis of its benefits, finding electoral characteristics to be useful in the prediction of polling error. Ultimately, I conclude that the adoption of a new, multi-level ontology of polling error centred on the importance of electoral heterogeneity not only offers a more comprehensive theoretical account of its sources than current understandings, but is also more specifically tailored to the reality of pre-election polling than existing alternatives. I also contend that it offers pronounced practical benefits, illuminating those circumstances in which polling error is likely to vary