Clarifying Agreement Calculations and Analysis for End-User Elicitation Studies

We clarify fundamental aspects of end-user elicitation, enabling such studies to be run and analyzed with confidence, correctness, and scientific rigor. To this end, our contributions are multifold. We introduce a formal model of end-user elicitation in HCI and identify three types of agreement analysis: expert , codebook , and computer . We show that agreement is a mathematical tolerance relation generating a tolerance space over the set of elicited proposals. We review current measures of agreement and show that all can be computed from an agreement graph . In response to recent criticisms, we show that chance agreement represents an issue solely for inter-rater reliability studies and not for end-user elicitation, where it is opposed by chance disagreement . We conduct extensive simulations of 16 statistical tests for agreement rates, and report Type I errors and power. Based on our findings, we provide recommendations for practitioners and introduce a five-level hierarchy for elicitation studies.

Extending Intel-x86 consistency and persistency: formalising the semantics of Intel-x86 memory types and non-temporal stores

Existing semantic formalisations of the Intel-x86 architecture cover only a small fragment of its available features that are relevant for the consistency semantics of multi-threaded programs as well as the persistency semantics of programs interfacing with non-volatile memory. We extend these formalisations to cover: (1) non-temporal writes, which provide higher performance and are used to ensure that updates are flushed to memory; (2) reads and writes to other Intel-x86 memory types, namely uncacheable, write-combined, and write-through; as well as (3) the interaction between these features. We develop our formal model in both operational and declarative styles, and prove that the two characterisations are equivalent. We have empirically validated our formalisation of the consistency semantics of these additional features and their subtle interactions by extensive testing on different Intel-x86 implementations.

Taking Up Thagard’s Challenge: A Formal Model of Conceptual Revision

Thagard (1992) presented a framework for conceptual change in science based on conceptual systems. Thagard challenged belief revision theorists, claiming that traditional belief-revision systems are able to model only the two most conservative types of changes in his framework, but not the more radical ones. The main aim of this work is to take up Thagard’s challenge, presenting a belief-revision-like system able to mirror radical types of conceptual change. We will do that with a conceptual revision system, i.e. a belief-revision-like system that takes conceptual structures as units of revisions. We will show how our conceptual revision and contraction operations satisfy analogous of the AGM postulates at the conceptual level and are able to mimic Thagard’s radical types of conceptual change.

Modeling and empirical verification of dependences of the influence of socio-economic situation of elderly persons on the level of resilience

В работе проведен эмпирический анализ влияния на уровень жизнестойкости параметров социально-экономического положения людей пожилого возраста на основе данных социологического опроса. Моделирование исследования включало выбор переменных с учетом критерия комплексности измеряемых параметров. Эмпирической базой для исследования являлись результаты анкетирования лиц пожилого возраста (выборочная совокупность 400 человек), проживающих в городах и сельской местности Томской обл. Для тестирования гипотез использовали моделирование и корреляционный анализ. Для выявления зависимости применена формальная модель взаимосвязи жизнестойкости с выделенными параметрами социально-экономического положения как системы показателей, к которым применимы методы математической статистики для выявления их влияния на укрепление жизнестойкости пожилых людей. Результаты исследования подтверждают влияние удовлетворенности материальным достатком на жизнестойкость людей пожилого возраста. Выявлены корреляции жизнестойкости и разных параметров, в том числе пола, места проживания и высшего образования. The work carried out an empirical analysis of the impact on the level of vitality of the parameters of the socio-economic situation of elderly people based on the data of a sociological survey. The modeling of the study of the influence included the choice of variables taking into account the criterion of the complexity of the measured parameters. The empirical basis for the study was the results of a survey (n=400) of elderly people living in cities and rural areas of the Tomsk region. Modeling and correlation analysis are used to test hypotheses. To identify the dependence, a formal model of the relationship of resilience with the selected parameters of the socio-economic situation is used as a system of indicators, to which the methods of mathematical statistics are applied to identify their impact on strengthening the resilience of older people. The results of the study confirm the influence of satisfaction with material prosperity on the resilience of elderly people. Correlations of resilience with different parameters, including gender, place of residence and higher education, were revealed.

Social Media and Press Freedom

As internet penetration rapidly expanded throughout the world, press freedom and government accountability improved in some countries but backslid in others. We propose a formal model that provides a mechanism that explains the observed divergent paths of countries. We argue that increased access to social media makes partial capture, where governments allow limited freedom of the press, an untenable strategy. By amplifying the influence of small traditional media outlets, higher internet access increases both the costs of capture and the risk that a critical mass of citizens will become informed and overturn the incumbent. Depending on the incentives to retain office, greater internet access thus either forces an incumbent to extend capture to small outlets, further undermining press freedom; or relieve pressure from others. We relate our findings to the cases of Turkey and Tunisia.

Corporate Diversification and Risk: Portfolio Effects and Resource Redeployability

By analogy with portfolio diversification by stock market investors, managers and researchers have often expected that firms that spread operations across product or geographic markets reduce risk. However, numerous exploratory studies in corporate strategy and in international business have not been able to robustly confirm this expectation. This study develops a formal model to scrutinize implications of corporate diversification for corporate risk. The model incorporates the key distinction of corporate diversification, economies of scope, that qualifies the analogy between corporate and portfolio diversification. The presence of a particular type of economies of scope, resource redeployability, not only inherently increases risk but it can also raise risk over the level in undiversified firms. The model uses determinants of resource redeployability from previous research to derive conditions with which corporate diversification enhances risk. The developed elaborate operationalization of corporate risk should facilitate future research and help corporate managers.

Mental Computations of Ideological Choice and Conviction: The Utility of Integrating Psycho-Economics and Bayesian Models of Belief

A quick scan of the political landscape reveals that people differ in the ideologies they embrace and advocate. Why do individuals prefer certain ideologies over others? A formal analysis of psychological needs and consumption desires suggests that it is possible to compute the subjective utility of selecting one ideology over another, as though it were a purchasing decision. Given resources, constraints, and available options, individuals can rationally choose the ideology that best matches or resonates with their interests. It is a compelling framework that can take into account how diverse ideologies satisfy people’s diverse and multidimensional psychological and material needs. This psycho-economic model is ambitious and informative, and I will argue that it can be even more encompassing and enlightening if it is expanded to incorporate two critical components of ideological cognition: (1) the nature of ideological conviction and extremism and (2) the dynamic, probabilistic mental computations that underlie belief formation, preservation, and change. Firstly, I will argue that a formal model of ideological choice cannot escape the question of the strength of ideological commitment. In other words, we need to ask not only about which ideologies individuals choose but also about how strongly they adhere to these ideologies once those are chosen. An analysis of ideological choice needs to be accompanied by an analysis of ideological conviction. Secondly, in order to build a robust sense of the rationality behind ideological thinking, it is useful to incorporate principles of uncertainty and probability-based belief updating into the formal model of ideological worldviews. Bayesian models highlight how human brains seek to build predictive models of the world by updating their beliefs and preferences in ways that are proportional to their prior expectations and sensory experiences. Consequently, incorporating Bayesian principles into the formal model of ideological choice will provide a more wholistic understanding of what happens when a mind enters the market for belief systems – and why a mind can, at times, purchase toxic doses of the ideologies that sellers and entrepreneurs offer on display.

Generic Methodology for Formal Verification of UML Models

This paper discusses a Unified Modelling Language (UML) based formal verification methodology for early error detection in the model-based software development cycle. Our approach proposes a UML-based formal verification process utilising functional and behavioural modelling artifacts of UML. It reinforces these artifacts with formal model transition and property verification. The main contribution is a UML to Labelled Transition System (LTS) Translator application that automatically converts UML Statecharts to formal models. Property specifications are derived from system requirements and corresponding Computational Tree Logic (CTL)/Linear Temporal Logic (LTL) model checking procedure verifies property entailment in LTS. With its ability to verify CTL and LTL specifications, the methodology becomes generic for verifying all types of embedded system behaviours. The steep learning curve associated with formal methods is avoided through the automatic formal model generation and thus reduces the reluctance of using formal methods in software development projects. A case study of an embedded controller used in military applications validates the methodology. It establishes how the methodology finds its use in verifying the correctness and consistency of UML models before implementation.

Premature repayment of fixed interest mortgage loans without compensation, a case of misguided consumer protection in the EU

Consumer protection shifts risks from consumers to businesses. This raises marginal costs and equilibrium prices. It is justified when markets are not strong enough to allocate contractual risks or accident risks efficiently, especially in cases of severe asymmetric information between suppliers and consumers. Consumer protection can then increase the consumer’s expected welfare from a contract. We test these considerations in a theoretical and empirical study on consumers' right to early repayment of mortgage loans without damage compensation to the creditor in the European Union. We show in a formal model that such a right can lead to an impairment of consumer welfare, compared with the traditional rule of expectation damages for breach of contract. This applies if the consumer is risk averse and repays a loan with a high interest rate in a low interest period to take up a new loan for the same project at lower interests. From a theoretical point of view, this right has no solid economic underpinning, if it is not restricted to cases of personal hardship of the consumer and serves an insurance purpose. We present empirical evidence supporting this argument. In a panel study on monthly mortgage interest rates of 23 EU Member States between 2005 and 2017 we show how interest rate spreads change with the level of consumer protection.

Securing Cloud Virtual Machine Image using Ethereum Blockchain

Virtual Machine Image (VMI) is the building block of cloud infrastructure. It encapsulates the various applications and data deployed at the Cloud Service Provider (CSP) end. With the leading advances of cloud computing, comes the added concern of its security. Securing the Cloud infrastructure as a whole is based on the security of the underlying Virtual Machine Images (VMI). In this paper an attempt has been made to highlight the various risks faced by the CSP and Cloud Service Consumer (CSC) in the context of VMI related operations. Later, in this article a formal model of the cloud infrastructure has been proposed. Finally, the Ethereum blockchain has been incorporated to secure, track and manage all the vital operations of the VMIs. The immutable and decentralized nature of blockchain not only makes the proposed scheme more reliable but guarantees auditability of the system by maintaining the entire VMI history in the blockchain.