Canonized Rewriting and Ground AC Completion Modulo Shostak Theories : Design and Implementation

AC-completion efficiently handles equality modulo associative and commutative function symbols. When the input is ground, the procedure terminates and provides a decision algorithm for the word problem. In this paper, we present a modular extension of ground AC-completion for deciding formulas in the combination of the theory of equality with user-defined AC symbols, uninterpreted symbols and an arbitrary signature disjoint Shostak theory X. Our algorithm, called AC(X), is obtained by augmenting in a modular way ground AC-completion with the canonizer and solver present for the theory X. This integration rests on canonized rewriting, a new relation reminiscent to normalized rewriting, which integrates canonizers in rewriting steps. AC(X) is proved sound, complete and terminating, and is implemented to extend the core of the Alt-Ergo theorem prover.Comment: 30 pages, full version of the paper TACAS'11 paper "Canonized Rewriting and Ground AC-Completion Modulo Shostak Theories" accepted for publication by LMCS (Logical Methods in Computer Science

Outline for legislative theory workshop

An outline for a nine-day workshop in legislative theory, methodology, and techniques in Lao PDR, which aimed at strengthening legislative drafters' ability to write drafting research reports

Top Management Team Diversity: A systematic Review

Empirical research investigating the impact of top management team (TMT) diversity on executives’ decision making has produced inconclusive results. To synthesize and aggregate the results on the diversity-performance link, a meta-regression analysis (MRA) is conducted. It integrates more than 200 estimates from 53 empirical studies investigating TMT diversity and its impact on the quality of executives’ decision making as reflected in corporate performance. The analysis contributes to the literature by theoretically discussing and empirically examining the effects of TMT diversity on corporate performance. Our results do not show a link between TMT diversity and performance but provide evidence for publication bias. Thus, the findings raise doubts on the impact of TMT diversity on performance

Ethics in educational research: review boards, ethical issues and researcher development

Educational research, and research in the Social Sciences more generally, has experienced a growth in the introduction of ethical review boards since the 1990s. Increasingly, universities have set up ethics review procedures that require researchers to submit applications seeking approval to conduct research. Review boards and the rules and conditions under which they operate have been criticised as obstructive, unnecessarily bureaucratic, and even unethical. At the same time, review boards and their procedures have been acknowledged as contributing to consideration of the ethical conduct of research. This paper explores the issues related to ethical review and examines the wider ethical considerations that may arise during the research process. The paper concludes that a purely administrative process of review is inadequate to ensure the ethical conduct of research, especially qualitative research. Rather, it is argued that ethical research entails the resolution of a potential series of ethical dilemmas as they arise during research. As such, the ethical conduct of research is a matter of researcher formation and development

Benchmarking in cluster analysis: A white paper

To achieve scientific progress in terms of building a cumulative body of knowledge, careful attention to benchmarking is of the utmost importance. This means that proposals of new methods of data pre-processing, new data-analytic techniques, and new methods of output post-processing, should be extensively and carefully compared with existing alternatives, and that existing methods should be subjected to neutral comparison studies. To date, benchmarking and recommendations for benchmarking have been frequently seen in the context of supervised learning. Unfortunately, there has been a dearth of guidelines for benchmarking in an unsupervised setting, with the area of clustering as an important subdomain. To address this problem, discussion is given to the theoretical conceptual underpinnings of benchmarking in the field of cluster analysis by means of simulated as well as empirical data. Subsequently, the practicalities of how to address benchmarking questions in clustering are dealt with, and foundational recommendations are made

Methods in Psychological Research

Psychologists collect empirical data with various methods for different reasons. These diverse methods have their strengths as well as weaknesses. Nonetheless, it is possible to rank them in terms of different critieria. For example, the experimental method is used to obtain the least ambiguous conclusion. Hence, it is the best suited to corroborate conceptual, explanatory hypotheses. The interview method, on the other hand, gives the research participants a kind of emphatic experience that may be important to them. It is for the reason the best method to use in a clinical setting. All non-experimental methods owe their origin to the interview method. Quasi-experiments are suited for answering practical questions when ecological validity is importa

Creating European Rights: National Values and Supranational Interests

This Article develops an explanation for the emergence of individual rights before the European Commission, one of the oldest and most powerful international organizations in existence today. I argue that, in the early days of the European Community, rights before the Commission were patterned on the laws and legal traditions of the dominant Member States. Changing political circumstances largely outside the control of the Commission and other European institutions gave rise to a number of discrete, historical challenges to their authority. Most of these challenges came from citizens with allegiances to minority, national constitutional symbols and practices who were determined to retain them in the face of European integration. To preserve and extend their authority, European institutions adopted these constitutional ideals and hence altered the nature of European rights. In developing this explanation, I draw upon a number of theories in political science. One of the longest-running debates over European integration is the balance between sovereign states and supranational institutions in setting the pace of European integration. While some scholars argue that traditional state interests and the balance of power among states are critical, others take supranational institutions--and their interest in expanding their powers and pushing forward integration--as the decisive force behind integration. My review of the origins of rights before the Commission shows that both sets of actors, at different points in time, were agents of rights. More importantly, the empirical analysis brings to light two important constraints on the ability of states and supranational institutions to design European rights to their advantage, often overlooked in the political science literature. The first is history writ large: understandings of fair and democratic government developed within the nation-state and representing the accumulation of experiences, beliefs, and norms over generations. The second is history writ small: episodic, external challenges to the authority of European institutions that serve as the context in which such institutions further their interests. These factors should be taken into account in explaining the rights that define what it is to be a European citizen today

Scientific Research about Climate Change Mitigation in Transport : A critical review

Peer reviewedPostprin