Optimization opportunities in human in the loop computational paradigm

An emerging trend is to leverage human capabilities in the computational loop at different capacities, ranging from tapping knowledge from a richly heterogeneous pool of knowledge resident in the general population to soliciting expert opinions. These practices are, in general, termed human-in-the-loop (HITL) computations. A HITL process requires holistic treatment and optimization from multiple standpoints considering all stakeholders: a. applications, b. platforms, c. humans. In application-centric optimization, the factors of interest usually are latency (how long it takes for a set of tasks to finish), cost (the monetary or computational expenses incurred in the process), and quality of the completed tasks. Platform-centric optimization studies throughput, or revenue maximization, while human-centric optimization deals with the characteristics of the human workers, referred to as human factors, such as their skill improvement and learning, to name a few. Finally, fairness and ethical consideration are also of utmost importance in these processes./p\u3e This dissertation aims to design solutions for each of the aforementioned stakeholders. The first contribution of this dissertation is the study of recommending deployment strategies for applications consistent with task requesters’ deployment parameters. From the worker’s standpoint, this dissertation focuses on investigating online group formation where members seek to increase their learning potential via collaboration. Finally, it studies how to consolidate preferences from different workers/applications in a fair manner, such that the final order is both consistent with individual preferences and complies with a group fairness criteria. The technical contributions of this dissertation are to rigorously study these problems from theoretical standpoints, present principled algorithms with theoretical guarantees, and conduct extensive experimental analysis using large-scale real-world datasets to demonstrate their effectiveness and scalability

Analysis of a Voting Method for Ranking Network Centrality Measures on a Node-aligned Multiplex Network

Identifying relevant actors using information gleaned from multiple networks is a key goal within the context of human aspects of military operations. The application of a voting theory methodology for determining nodes of critical importance—in ranked order of importance—for a node-aligned multiplex network is demonstrated. Both statistical and qualitative analyses on the differences of ranking outcomes under this methodology is provided. As a corollary, a multilayer network reduction algorithm is investigated within the context of the proposed ranking methodology. The application of the methodology detailed in this thesis will allow meaningful rankings of relevant actors to be produced on a multiplex network

Voting beyond vetoing:Variations in agenda-setting and balloting procedures for multi-option referendums

Referendums most commonly occur in a binary format in which citizens either accept or reject a policy proposal. In practice, many voters are unlikely to be fully satisfied with either of these two options. They may have reservations about the policy or may only be willing to accept it conditional on some amendments. A binary referendum does not allow voters to express preferences for variations on the policy proposal. This may cause voters to reject a proposal despite being in favour of new policy on the topic. Such a rejection also makes it difficult for policymakers to adequately interpret a referendum outcome. Multi-option referendums could be an effective alternative, as they offer voters a choice between three or more policy options. They result in a single winning option which details the most desired policy route. Compared to binary referendums, multi-option formats have several advantages but also face several challenges, neither of which have been structurally analysed in prior research. Through four academic articles, this thesis explores various design questions relevant to multi-option referendums. The findings contribute to our insights into the implications of design variations for the empowerment of citizens and the materialisation of clear voting outcomes. This research considers two different phases of the referendum process. First, the agenda-setting phase raises the question of who decides when a multi-option referendum is held and which topics and policy proposals are on the ballot. Secondly, the balloting phase raises questions on how votes are expressed on the different options and how they are combined into a final result. The practical manifestations of various advantages and challenges in the two phases are explored by analysing both empirical experiences and new survey data. The empirical research presents a new dataset of national-level multi-option referendums. It discusses what we can learn from how multi-option referendums have been designed and conducted in practice. It also maps different processes of agenda-setting and explores the role of citizens in this phase. The survey research structurally compares the effects of different balloting variations in two separate studies. The first study compares voting on referendum ballots using a single question or multiple questions. The second study compares voting results between a multi-option ballot and a binary ballot. The research findings imply that multi-option referendums can be an effective instrument for citizen participation when more than two policy scenarios are possible and enjoy support. They can empower citizens both as voters, being offered more choice, and as agenda-setters, enabling them to contribute to the ballot content. Variations in terms of who selects the ballot options and which methods are used to vote on the options each have their own advantages and limitations. The optimal choice may depend on the context and desirable characteristics of the referendum. One general and pressing recommendation for balloting is to use voting methods in which voters can vote for more than one proposal. With such alternative voting methods, voters can either approve of several proposals or rank them according to their relative preferences. This greatly increases the likelihood of yielding a clear majority outcome. The thesis concludes that though not all referendums may benefit from a multi-option format, the multi-option format should be seriously considered. It maintains the advantages of referendums as an accessible instrument to participate in policymaking on a concrete topic, whilst providing more choice to voters and greater clarity on preferred policy routes. The findings on the characteristics of various ballot designs, voting methods and agenda-setting models can help practitioners and academics to evaluate the relative advantages and limitations of various multi-option designs and to weigh them against the simpler but also more limitative binary referendum design

Towards completing the puzzle: complexity of control by replacing, adding, and deleting candidates or voters

We investigate the computational complexity of electoral control in elections. Electoral control describes the scenario where the election chair seeks to alter the outcome of the election by structural changes such as adding, deleting, or replacing either candidates or voters. Such control actions have been studied in the literature for a lot of prominent voting rules. We complement those results by solving several open cases for Copelandα, maximin, k-veto, plurality with runoff, veto with runoff, Condorcet, fallback, range voting, and normalized range voting

Assessment of vulnerability to climate change: theoretical and methodological developments with applications to infrastructure and built environment

Assessing vulnerability to climate change can help policymakers in incorporating climate futures in planning and in better allocating adaptation resources. Indicator Based Vulnerability Assessment (IBVA) has been widely used because it is relatively simple to design, implement and communicate. However, this approach faces significant difficulties from conceptual, theoretical and methodological points of view. A number of assumptions are typically made in methods used for aggregation of indicators—a linear, monotonic relationship between indicator and vulnerability; complete compensation between indicators; precise knowledge of vulnerable systems by stakeholders who provide input data for the assessment exercise—none of which usually hold in reality. Following a meta-analysis of the IBVA literature, the thesis proposes a) a general mathematical framework for vulnerability assessment that better identifies sources of uncertainty and non-linearity; b) a new IBVA assessment methodology, and associated computer tool, based on a pair-wise outranking approach borrowed from decision science; the methodology can represent various sources of uncertainty, different degree of compensation between indicators and different types of non-linearity in the relationship between indicators and vulnerability and; c) a system dynamics model, integrated in the above framework, for studying vulnerability of infrastructure systems and better representing the mechanistic interdependency of their components. These methods are applied to a real-life assessment of the vulnerability to sea-level rise of communities and infrastructure systems in Shoalhaven, south of Sydney, at local scale. The assessment is conducted in collaboration with the Shoalhaven council and includes an analysis of the sensitivity of vulnerability rankings to community preferences. In addition, the effect of using an outranking framework on the way vulnerability is conceptualized by stakeholders is critically appraised

Assessment of vulnerability to climate change: theoretical and methodological developments with applications to infrastructure and built environment

Assessing vulnerability to climate change can help policymakers in incorporating climate futures in planning and in better allocating adaptation resources. Indicator Based Vulnerability Assessment (IBVA) has been widely used because it is relatively simple to design, implement and communicate. However, this approach faces significant difficulties from conceptual, theoretical and methodological points of view. A number of assumptions are typically made in methods used for aggregation of indicators—a linear, monotonic relationship between indicator and vulnerability; complete compensation between indicators; precise knowledge of vulnerable systems by stakeholders who provide input data for the assessment exercise—none of which usually hold in reality. Following a meta-analysis of the IBVA literature, the thesis proposes a) a general mathematical framework for vulnerability assessment that better identifies sources of uncertainty and non-linearity; b) a new IBVA assessment methodology, and associated computer tool, based on a pair-wise outranking approach borrowed from decision science; the methodology can represent various sources of uncertainty, different degree of compensation between indicators and different types of non-linearity in the relationship between indicators and vulnerability and; c) a system dynamics model, integrated in the above framework, for studying vulnerability of infrastructure systems and better representing the mechanistic interdependency of their components. These methods are applied to a real-life assessment of the vulnerability to sea-level rise of communities and infrastructure systems in Shoalhaven, south of Sydney, at local scale. The assessment is conducted in collaboration with the Shoalhaven council and includes an analysis of the sensitivity of vulnerability rankings to community preferences. In addition, the effect of using an outranking framework on the way vulnerability is conceptualized by stakeholders is critically appraised

Initiative on Quality Shareholders Highlights

Highlights of a research initiative that formalizes the longstanding intuition that the sorts of shareholders a company attracts influences its performance. Contains lists of the best shareholders in corporate America, measured by long holding periods and high portfolio concentration, and lists of the companies that attract such shareholders in high density. Notes and explains how such shareholders and companies have been prone to outperform rivals. Explores what quality shareholders look for in companies and a dozen of the practices and policies that, evidence shows, companies can use to attract quality shareholders. Includes bibliographic references and suggestions for further research