Similarity measures and diversity rankings for query-focused sentence extraction

Query-focused sentence extraction generally refers to an extractive approach to select a set of sentences that responds to a specific information need. It is one of the major approaches employed in multi-document summarization, focused summarization, and complex question answering. The major advantage of most extractive methods over the natural language processing (NLP) intensive methods is that they are relatively simple, theoretically sound – drawing upon several supervised and unsupervised learning techniques, and often produce equally strong empirical performance. Many research areas, including information retrieval and text mining, have recently moved toward the extractive query-focused sentence generation as its outputs have great potential to support every day‟s information seeking activities. Particularly, as more information have been created and stored online, extractive-based summarization systems may quickly utilize several ubiquitous resources, such as Google search results and social medias, to extract summaries to answer users‟ queries.This thesis explores how the performance of sentence extraction tasks can be improved to create higher quality outputs. Specifically, two major areas are investigated. First, we examine the issue of natural language variation which affects the similarity judgment of sentences. As sentences are much shorter than documents, they generally contain fewer occurring words. Moreover, the similarity notions of sentences are different than those of documents as they tend to be very specific in meanings. Thus many document-level similarity measures are likely to perform well at this level. In this work, we address these issues in two application domains. First, we present a hybrid method, utilizing both unsupervised and supervised techniques, to compute the similarity of interrogative sentences for factoid question reuse. Next, we propose a novel structural similarity measure based on sentence semantics for paraphrase identification and textual entailment recognition tasks. The empirical evaluations suggest the effectiveness of the proposed methods in improving the accuracy of sentence similarity judgments.Furthermore, we examine the effects of the proposed similarity measure in two specific sentence extraction tasks, focused summarization and complex question answering. In conjunction with the proposed similarity measure, we also explore the issues of novelty, redundancy, and diversity in sentence extraction. To that end, we present a novel approach to promote diversity of extracted sets of sentences based on the negative endorsement principle. Negative-signed edges are employed to represent a redundancy relation between sentence nodes in graphs. Then, sentences are reranked according to the long-term negative endorsements from random walk. Additionally, we propose a unified centrality ranking and diversity ranking based on the aforementioned principle. The results from a comprehensive evaluation confirm that the proposed methods perform competitively, compared to many state-of-the-art methods.Ph.D., Information Science -- Drexel University, 201

Condensing Information: From Supervised To Crowdsourced Learning

The main focus of this dissertation is new and improved ways of bringing high quality content to the users by leveraging the power of machine learning. Starting with a large amount of data we want to condense it into an easily digestible form by removing redundant and irrelevant parts and retaining only important information that is of interest to the user. Learning how to perform this from data allows us to use more complex models that better capture the notion of good content. Starting with supervised learning, this thesis proposes using structured prediction in conjunction with support vector machines to learn how to produce extractive summaries of textual documents. Representing summaries as a multivariate objects allows for modeling the dependencies between the summary components. An efficient approach to learning and predicting summaries is still possible by using a submodular objective/scoring function despite complex output space. The discussed approach can also be adapted to unsupervised setting and used to condense information in novel ways while retaining the same efficient submodular framework. Incorporating temporal dimension into summarization objective lead to a new way of visualizing flow of ideas and identifying novel contributions in a time-stamped corpus, which in turn help users gain a high level insight into evolution of it. Lastly, instead of trying to explicitly define an automated function used to condense information, one can leverage crowdsourcing. In particular, this thesis considers user feedback on online user-generated content to construct and improve content rankings. An analysis of a real-world dataset is presented and results suggest more accurate models of actual user voting patterns. Based on this new knowledge, an improved content ranking algorithm is proposed that delivers good content to the users in a shorter timeframe

An Agenda to Strengthen Our Right to Know: Empowering Citizens with Environmental, Health, and Safety Information

Public engagement and access to environmental and public health information are vital democratic tools. A lack of government openness impairs everything from preventing – and cleaning up – oil spills to protecting children from toxic chemicals. The need to break down information barriers and bring the public back into the policymaking process is greater than ever. A lack of access to quality information – and to policymakers – hurts people and the landscapes we cherish and depend on.Today, individuals and governments at all levels are facing various environmental and public health dilemmas. Dealing with these issues requires open and accountable government processes; expanded and improved data collection, analysis, and distribution; and greater public engagement. Such improvements are needed in order to tackle the full spectrum of threats, from identifying the health hazards of the tens of thousands of chemicals in commerce, to improved monitoring of pollution, to filling the huge data gaps in our climate policies.After more than a year of work, a broad coalition of groups and individuals active in protecting human and environmental health have taken a major step on the path toward greater government transparency and public participation. These public interest advocates have produced a comprehensive list of policy recommendations that would greatly strengthen our right to know and increase the government's level of community engagement. The recommendations outlined in this document are an action plan for the federal government; a plan that is bold yet feasible, ambitious yet realistic. Now the opportunity to advance this proactive agenda is upon us. We call on our leaders and decision makers to take up this call to action and ensure that every person in the country has access to the information needed to make decisions that enable all of us to live, work, play, and learn within a healthy environment

Avoiding unhelpful statements: A proposed theoretical measure of readiness to work with transgender clients

When transgender people most need help, many face hostility and inadequate care from their health providers, including psychologists. This hostility is not surprising given widespread lack of familiarity with transgender issues or perspectives amongst clinicians. Even amongst those who hold the stance of openness to the other, most still have considerable difficulty working with transgender clients. Transgender training efforts vary in quality; some even appear to worsen attitudes towards transgender clients. Given these risks, it is crucial that clinical training directors and supervisors evaluate trainees\u27 abilities to facilitate respectful initial conversations with transgender clients. This project proposed an objective instrument for assessing a mental health clinician, or clinical trainees\u27 ability to discriminate between helpful and unhelpful responses commonly made in the initial clinical encounters with transgender clients. Development of the instrument is grounded in a combination of theoretical and empirical literature on the topic and is synthesized with the personal and professional experiences of the primary researcher as a transgender person and emerging clinician. This study utilized systematic expert review to examine the validity of this proposed instrument

Characteristics of Science, Technology, Engineering, And Mathematics Mentoring Relationship Practices In Secondary Education Settings: A Case Study

The use of science, technology, engineering, and mathematics (STEM) mentors in public school systems and other organizations has grown comparably with our economy’s increasing demand for STEM industry professionals. However, inspiring students to pursue STEM careers by using STEM industry professionals as mentors requires an understanding of effective mentor practices. Limited research exists that focuses on the mentoring practices students respond to as they make academic and career plans. The purpose of this study was to investigate and identify practices that promote STEM careers among youth. The study sought to answer the question, “What STEM mentor practices, behaviors, and roles do students identify as increasing their interest in pursuing STEM careers?” This study used a qualitative case study methodology. Golden Meadows School District was selected due to its extensive secondary education STEM mentoring programming. STEM education courses and activities are offered district-wide at the Center for STEM Instruction and Innovation (CSII). Golden Meadows was also chosen for the longevity of its program and the variety of STEM-focused project teams. The project teams were supported by industry mentors recruited from local businesses. The study focused on the perspectives of mentees working with industry mentors from various STEM disciplines. Students in the 11th and 12th grades were asked to participate in interviews. Participants answered questions about mentoring experiences that influenced their plans to pursue STEM professions. Interview responses and project team artifact review were used to analyze mentee perspectives. Two themes emerged from the findings which defined practices identified by mentees. The findings revealed that mentees pursuit of STEM careers was influenced by mentor practices that built mentee self-confidence and a comprehensive understanding of STEM careers. The study is supported by previous research focused on the value of mentoring and its use to positively influence young people

What networks do to firms and what firms do to networks: Evolution of alliance portfolios in networked markets

This study explores the question of how alliance portfolios change over time. In the setting of the U.S. wireless gaming market, I collected real-time and longitudinal data on entrepreneurial game publishers over two and a half years. This process revealed that alliance portfolios of firms can grow or deteriorate rapidly through virtuous or vicious cycles, depending on their starting position in a networked market. Those firms in a virtuous cycle have the additional advantage that they can use resource-dependence strategies to fuel the virtuous cycle. Finally, I find that changes in a firm's alliance portfolio occur simultaneously with other firm-level changes, such as physical growth, new rounds of financing, public offering and game coverage. The findings have potential contributions to literature at the firm, portfolio, and network levels. Overall, the picture provided is one that advocates multi-level and longitudinal analysis for the understanding of firm, portfolio, and network-level outcomes deriving from firm-level interactions and portfolio strategies.Alliance portfolios; firm evolution; strategy; resource dependence;

Human Resource Officer\u27s Perspectives on Recruitment and Hiring Practices of Diverse Candidates

A wealth of research supports the positive impact minority teachers have on all students, but especially minority students. Benefits include an increase in academic achievement, an increase in educational engagement, and an overall sense of self-efficacy and autonomy. Unfortunately minority teachers and teachers of color are significantly underrepresented in the United States teaching workforce compared to their White counterparts. Challenges for diversifying the teaching workforce include historical factors of racism and suppression, the Whiteness of educator preparation programs as the prevailing ideology, and the presence of toxic work environment conditions during field placements and employment. While many historical and contemporary factors regarding recruitment and retention have been investigated, the perspectives from those individuals primarily responsible for recruitment and hiring are missing from the literature. This study investigated the perspectives of human resource officers from small-rural school divisions in a middle Atlantic state, and explored how and to what extent their recruitment and hiring practices support a diverse teaching workforce. The methods used to complete the study incorporated a phenomenological qualitative design utilizing a semi-structured interview format. The participant recruitment was based on the specific criteria of human resource officers who are employed and serve in divisions identified as rural. Data collected through the interviews were coded, analyzed, and clustered into themes using phenomenological reduction and bracketing. Several themes emerged from the data analysis: participant pathway to the position of HRO, division internal structures and processes for recruitment and hiring, characteristics prioritized when selecting and hiring candidates, barriers and successful strategies identified for recruitment and hiring diverse candidates, and strategies and initiatives identified as needed in order to increase diversity within schools. The overall findings were synthesized utilizing the Critical Race Theory, with a predominant focus on counter-storytelling and permanence of racism. An analysis of the interview testimonies by participant’s race reveal several important and distinct themes which provide a unique, culturally relevant perspective: the overall importance of diversity, the significance of diversity recruiting diversity, and the cultural differences in interactions between administrators and diverse teachers. In addition, the permanence of racism was a common thread revealed through all of the interviews where multiple examples were provided of everyday racism, “antiracist” racism, and everyday racism

Decision making theory with geographic information systems support

Decisions are made with varying degrees of effectiveness and efficiency and are influenced by a myriad of internal and external forces. Decision Support Systems (DSS) software can effectively aid decision making through processing the facts and producing meaningful outputs for use by the person or team in making the final choice. Geographic Information Systems (GIS), a form of DSS, are very effective when locational data are present. This thesis talks about using GIS software in decision making procedures

Evaluating the impact of patient and public involvement on cancer research outcomes: A UK mixed methods study

Interest in patient and public involvement (PPI) in healthcare research has been growing. In the UK and internationally there is increasing demand for researchers to demonstrate the value of PPI both in their work and to funding bodies. Existing evidence demonstrates that reporting of PPI has been limited and inconsistent. In particular, whilst there is growing evidence about the use and efficacy of PPI in research processes, little is known about how to evaluate the impact of PPI on research outcomes. The aim of this research was therefore to evaluate the impact of PPI on cancer research outcomes. An interpretivist and pragmatist methodology was adopted to explore how the impact of PPI on cancer research outcomes can be evaluated, using a mixed methods sequential design. In phase one, 23 in-depth interviews were conducted with patients, researchers and stakeholders from the East Midlands region to explore perceptions of the impact of PPI on research outcomes and their experiences of involving patients and the public in research outcomes. In phase two, a modified Delphi study was conducted with 35 experts across England in order to refine and enhance knowledge about the impact of PPI on research outcomes. Data were analysed using Braun and Clarke (2006). End user involvement was embedded in the study at key stages and evaluated using the GRIPP 2 checklist (Staniszewska 2017). Limitations to this research study included the paucity of black and minority ethnic participants and being only East Midlands focused in phase 1. Findings from the interviews and the Delphi study demonstrated that there are several factors which shape the impact of PPI on research outcomes. These are: PPI in commissioning; PPI in research processes; PPI in dissemination; PPI in implementation; information and communication technology; power and leadership; resources and the political context; networks; and wanting to make a difference. Data show that the evaluation of the impact of PPI on research outcomes was achievable at four stages: pre-implementation, partial-implementation, during-implementation and post-implementation. Reflexive analysis of the use of end user involvement within the study included a consideration of the challenges of involvement for PhD researchers. Drawing on theoretical insights about PPI in research and work from the field of implementation science, this thesis makes an original contribution by arguing three main points. First, that PPI can be considered as a complex intervention (Craig et al. 2008). Second, that as a complex intervention, the impact of PPI on research outcomes can therefore be evaluated using the Consolidated Framework for Implementation Research (CFIR) (Damschroder et al. 2009). Third, using the CFIR, particularly the domain of ‘process of implementation’, enhances understanding about the success or failure of the implementation of PPI in practice. The data highlight particular attention should be given to the time and resource implications required to conduct effective evaluation of the impact of PPI on research outcomes