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Regulatory Conformance Checking: Logic and Logical Form University of Pennsylvania ScholarlyCommons Publicly Accessible Penn Dissertations Fall 2010 Regulatory Conformance Checking: Logic and Logical Form Nikhil Dinesh University of Pennsylvania, [email protected] Follow this and additional works at: https://repository.upenn.edu/edissertations Part of the Logic and Foundations of Mathematics Commons, Other Computer Engineering Commons, and the Semantics and Pragmatics Commons Recommended Citation Dinesh, Nikhil, "Regulatory Conformance Checking: Logic and Logical Form" (2010). Publicly Accessible Penn Dissertations. 295. https://repository.upenn.edu/edissertations/295 This paper is posted at ScholarlyCommons. https://repository.upenn.edu/edissertations/295 For more information, please contact [email protected]. Regulatory Conformance Checking: Logic and Logical Form Abstract We consider the problem of checking whether an organization conforms to a body of regulation. Conformance is studied in a runtime verification setting. The egulationr is translated to a logic, from which we synthesize monitors. The monitors are evaluated as the state of an organization evolves over time, raising an alarm if a violation is detected. An important challenge to this approach comes from the fact that regulations are commonly expressed in natural language. The translation to logic is difficult. Our goal is to assist in this translation by: (a) the design of logics that let us formalize regulation one sentence at a time, and (b) the use of natural language processing as an aid in the sentential translation. There are many features that are needed in a logic, to accommodate a sentential translation of regulation. We study two features, motivated by a case study. First, statements in regulation refer to others for conditions or exceptions. Second, sentences in regulation convey legal concepts, e.g., obligation and permission. Obligations and permissions can be nested to convey concepts, such as, rights. We motivate and design a logic to accomodate these two features of regulatory texts. The common theme is the importance of the notion of {\em saying} in such constructs. We begin by extending linear temporal logic to allow statements to refer to others. Inter-sentential references are expressed via the use of a predicate, called "says", whose interpretation is determined by inferences from laws. The "says" predicate offers a unified analysis of ariousv kinds of inter-sentential references, e.g., priorities of exceptions over rules, and references to definitions or list items. We then augment the logic with obligation and permission, by considering problems in access control and conformance. Saying and permission are combined using an axiom that permits a principal to speak on behalf of another. The combination yields benefits to both applications. For access control, we overcome the problematic interactions between hand-off and classical reasoning. For conformance, we obtain a characterization of legal power by nesting saying with obligation and permission. A useful fragment of the logic has a polynomial time decision procedure. Finally, we turn to the use of natural language processing to translate a sentence to logic. We study one component of the translation in a supervised learning setting. Linguistic theories have argued for a level of logical form as a prelude to translating a sentence into logic. Logical form encodes a resolution of scope ambiguties. We define a estrictedr kind of logical form, called abstract syntax trees (ASTs), based on the logic developed. Guidelines for annotating ASTs are formulated, using a case study of the Food and Drug Administration's Code of Federal Regulations. We describe experiments on a modest-sized corpus, of about 200 sentences, annotated with ASTs. The main step in computing ASTs is the ordering or ranking of operators. We adapt a learning model for ranking to order operators. Features are designed by studying subproblems, such as, disambiguating between de re and de dicto interpretations. We obtain an F-score of 90.6% on the set of pairwise ordering decisions. Degree Type Dissertation Degree Name Doctor of Philosophy (PhD) Graduate Group Computer and Information Science First Advisor Aravind K. Joshi Second Advisor Insup Lee Keywords modal logic, access control, conformance, deontic logic, logical form, scope Subject Categories Logic and Foundations of Mathematics | Other Computer Engineering | Semantics and Pragmatics This dissertation is available at ScholarlyCommons: https://repository.upenn.edu/edissertations/295 REGULATORY CONFORMANCE CHECKING: LOGIC AND LOGICAL FORM Nikhil Dinesh A DISSERTATION in Computer and Information Science Presented to the Faculties of the University of Pennsylvania in Partial Fulfillment of the Requirements for the Degree of Doctor of Philosophy 2010 SupervisorofDissertation Co-Supervisor AravindK.Joshi InsupLee Professor, Computer and Information Science Professor, Computer and Information Science Graduate Group Chairperson Jianbo Shi, Associate Professor, Computer and Information Science Dissertation Committee: Claire Cardie, Professor, Computer Science, Cornell University Steven O. Kimbrough, Professor, Operations and Information Management Fernando C. N. Pereira, Professor, Computer and Information Science Oleg Sokolsky, Research Associate Professor, Computer and Information Science REGULATORY CONFORMANCE CHECKING: LOGIC AND LOGICAL FORM COPYRIGHT Nikhil Dinesh 2010 Acknowledgements My first thanks must go to my two advisors Aravind Joshi and Insup Lee, and com- mittee chair Oleg Sokolsky. They have contributed significantly to all sections of this thesis. Initially, my research progress was slow to non-existent, and I thank them for their patience with all my ideas – the good, the bad, and the ugly. Aravind has helped shaped my thinking about problems at a high level, Insup with attention to detail, and Oleg with that gray area in the middle. This thesis was shaped by a great committee, in addition to Oleg. Fernando Pereira has been a great source of ideas throughout grad school. A quick conversation with him usually reveals about ten things that I haven’t thought about. I thank Steve Kimbrough for several illuminating discussions about the logical aspects of this thesis, and Claire Cardie for getting me thinking about different levels of evaluation in the computation of logical form. I was fortunate to collaborate with researchers in different areas at Penn. Being a part of the team that built the Penn Discourse Treebank was a lot of fun. The adjudication sessions, with Eleni Miltsakaki, Alan Lee, Rashmi Prasad, and Bonnie Webber, helped foster my interest in annotation. I thank Jana Beck for helping with the inter-annotator agreement experiments in this thesis, and Mitch Marcus for suggesting self-agreement. And, the members of the real-time systems group for various discussions, especially David Arney, Arvind Easwaran, and Michael May. This work would not have been possible without the support of David Hislop from the ARO and Paul Jones from the FDA. They introduced us to the problem of iii conformance checking, and encouraged us to pursue it over the years. Frustration in research can only be overcome through sport! Thanks to Michael Kearns for several years of squash, Adam Aviv and Lukasz Abramowicz for tennis sessions, and Alex Kulesza and Jennifer Gillenwater for running lessons. Despite my need to spend quality time with my computer, I’ve enjoyed hanging out with several fellow students. Barbecues and poker sessions will not be the same without Ameesh Makadia, Ryan McDonald, and Mirko Visontai. John Blitzer and I explored a curious combination of coffee and Mediterranean history, with a liberal dash of linguistics and machine learning. Thanks to Yuan Ding for lectures on the musculature of saber-toothed cats and other animals. And, to Liang Huang and Bei Xiao for their company during dinners. Axel Bernal and I were the last (of our era) left behind, and I’m grateful to him, with some reservations, for making me give up all the food I like. I also thank Anne Bracy, Andrew McGregor, Nick Montfort, Arun Raghavan, Hana Wallach, and Kilian Weinberger, for their friendship. My friends from the early years of grad school – Abhijeet, Narayanan, Pranav, and Prasanna, and my undergraduate years – Girish, Subhash, and Roopesh, made those periods significantly more enjoyable. And, finishing up would not have been so much fun, if I hadn’t shared it with Mythili. Some sentiments are best expressed with two negations and a counterfactual. I’m thankful to have a wonderful family in India and the USA. Thanks to the Menons – Govind, Eva, David, Sunitha, and Kavitha, for their hospitality at Thanks- giving. And, to the Sanjays – Nisha, Kamya, Nino, and the man himself, for wonderful Christmases. Space prohibits acknowledging the entire family. But, I would like to thank my maternal and paternal grandparents for all their love and support, and my cousins – Aditya, Ashwin, Menaka, Mridula, Niranjan, and Rajiv. Finally, I thank my parents, Dinesh and Lata, and my sister, Nandita. A proper acknowledgement of their contributions would be as long as the thesis. So, in the interests of saving half a rain forest, I conclude by dedicating this thesis to them. iv ABSTRACT REGULATORY CONFORMANCE CHECKING: LOGIC AND LOGICAL FORM Nikhil Dinesh Aravind K. Joshi and Insup Lee We consider the problem of checking whether an organization conforms to a body of regulation. Conformance is studied in a runtime verification setting. The regula-
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