Everyday life revolves around the discovery and curation of digital information. People search the Web continuously, from quickly looking up the information needed to complete a task, to endlessly searching for inspiration and knowledge. A variety of studies have modeled information seeking strategies and characterized information seeking and curation activities on the Web. However, there is a lack of research on how existing Web applications support the discovery and curation of information, especially concerning the motivations behind them and how different approaches can be compared. In this thesis, I present a study of information discovery tools and how they relate to the nature of information seeking. I propose a conceptual framework that deals with Web application design elements that support different aspects of information discovery and curation. This framework can be used when designing, evaluating or updating Web applications. / Graduate / 0984

Thesis (LL. M.)--Judge Advocate General's School, U.S. Army, 1968. / "April, 1968." Typescript. Includes bibliographical references (leaves 71-72). Also issued in microfiche.

Broadly, this study focuses on roles of sell-side analysts and examines the determinants and consequences of information discovery and stock timing roles by sell-side analysts. We also re-examine reiterations of prior recommendations by sell-side analysts. In Chapter 1, the contribution is to document that analysts add value by engaging in discovery of private information and this value addition is greater than that due to interpretation of public news or stock timing. The innovation in this Chapter is to read over 3,700 analyst reports from Investext and explicitly identify whether the report contains discovery, interpretation, and/or timing. Analysts discover new information by talking to management sources (personal meetings, investor meetings, and conference calls) or non-management sources (such as channel checks). We find that information discovery is prevalent in 17% of the reports. The cumulative abnormal return (CAR) for reports containing discovery are 6.3% for upgrades and -10.6% for downgrades. The CARs are higher for reports containing discovery relative to those containing interpretation or timing. We find that economic determinants predict whether a report will contain discovery. Discovery from management sources is more likely for reports in the pre-Reg FD period and for reports by optimistic analysts. Discovery from non-management sources is more likely for reports written by All-Star analysts, and for firms that have high information asymmetry and those that are followed by more analysts. In Chapter 2, the contribution is to introduce and document a third role that analysts play that is also valuable to investors, which we term "stock timing." Specifically, we define a timing report as one where the analyst revises his recommendation but does not revise the Price Target or any of the 23 fundamental drivers of stock price (such as EPS, FCF) tracked by I/B/E/S. Because the analyst maintains the same price target as in his prior report but still revises his recommendation, such timing calls are contrarian valuation calls. Analysts issue timing downgrades (upgrades) in response to price increases (declines) since the release of their prior report on the firm. 30% of all revisions are timing reports, indicating the importance of the timing role played by analysts. If analysts have timing ability, then markets should react to the release of the timing report and we should observe that economic determinants explain the cross-sectional variation in timing ability. We find the 3-day announcement return is over 2% in magnitude, 62% of the reports are winners (have announcement returns that have the correct sign), 10% of the reports are large enough to be considered influential, and 37% of the reports are persistent winners. These results suggest that analysts have timing ability. The ability to time is similar is magnitude to information interpretation but smaller compared to information discovery. We find considerable cross-sectional and time-series variation in timing ability. We find that the probability of issuing a timing report is positively related to the opportunities to time the stock provided by potential mispricing. Conditional on issuing a timing report, the probability of issuing a winner, an influential winner, or a persistent winner is positively related to analyst experience and negatively related to the costs associated with issuing a timing report. In Chapter 3, we document that recommendation reiterations are not homogeneous and there is a large subset of reiterations that are as much valued by investors as recommendation revisions. We combine Detail History file containing the measures tracked by I/B/E/S (Price Target, EPS, etc.) and Recommendation file to create the full time series of recommendations (initiations, reiterations, and revisions) made by each analyst for each firm for 14 years from 1999 to 2012. By adopting a modified version of "filling in the holes" method, we find that recommendation reiterations are prevalent, consisting of about 80% of recommendations for our 14-year sample period. Second, market response to recommendation reiterations increases monotonically from Reiteration: Strong Sell to Reiteration: Strong Buy. Third, reiterations coupled with contemporary changes in price targets and/or earning forecasts bring substantial absolute abnormal stock returns to investors. Lastly, when we replicate what Loh and Stulz (2011), we find that the number of reiterations which are influential is more than twice that of recommendation revisions that are influential. / Business Administration/Finance

Graph-structured databases are widely prevalent, and the problem of effective search and retrieval from such graphs has been receiving much attention recently. For example, the Web can be naturally viewed as a graph. Likewise, a relational database can be viewed as a graph where tuples are modeled as vertices connected via foreign-key relationships. Keyword search querying has emerged as one of the most effective paradigms for information discovery, especially over HTML documents in the World Wide Web. One of the key advantages of keyword search querying is its simplicity – users do not have to learn a complex query language, and can issue queries without any prior knowledge about the structure of the underlying data. The purpose of this dissertation was to develop techniques for user-friendly, high quality and efficient searching of graph structured databases. Several ranked search methods on data graphs have been studied in the recent years. Given a top-k keyword search query on a graph and some ranking criteria, a keyword proximity search finds the top-k answers where each answer is a substructure of the graph containing all query keywords, which illustrates the relationship between the keyword present in the graph. We applied keyword proximity search on the web and the page graph of web documents to find top-k answers that satisfy user’s information need and increase user satisfaction. Another effective ranking mechanism applied on data graphs is the authority flow based ranking mechanism. Given a top-k keyword search query on a graph, an authority-flow based search finds the top-k answers where each answer is a node in the graph ranked according to its relevance and importance to the query. We developed techniques that improved the authority flow based search on data graphs by creating a framework to explain and reformulate them taking in to consideration user preferences and feedback. We also applied the proposed graph search techniques for Information Discovery over biological databases. Our algorithms were experimentally evaluated for performance and quality. The quality of our method was compared to current approaches by using user surveys.

Many organizations are trying to re-create the ‘Google experience’, to find and exploit their own corporate information. However, there is evidence that finding information in the workplace using search engine technology has remained difficult, with socio-technical elements largely neglected in the literature. Explication of the factors and generative mechanisms (ultimate causes) to effective search task outcomes (user satisfaction, search task performance and serendipitous encountering) may provide a first step in making improvements. A transdisciplinary (holistic) lens was applied to Enterprise Search and Discovery capability, combining critical realism and activity theory with complexity theories to one of the world’s largest corporations. Data collection included an in-situ exploratory search experiment with 26 participants, focus groups with 53 participants and interviews with 87 business professionals. Thousands of user feedback comments and search transactions were analysed. Transferability of findings was assessed through interviews with eight industry informants and ten organizations from a range of industries. A wide range of informational needs were identified for search filters, including a need to be intrigued. Search term word co-occurrence algorithms facilitated serendipity to a greater extent than existing methods deployed in the organization surveyed. No association was found between user satisfaction (or self assessed search expertise) with search task performance and overall performance was poor, although most participants had been satisfied with their performance. Eighteen factors were identified that influence search task outcomes ranging from user and task factors, informational and technological artefacts, through to a wide range of organizational norms. Modality Theory (Cybersearch culture, Simplicity and Loss Aversion bias) was developed to explain the study observations. This proposes that at all organizational levels there are tendencies for reductionist (unimodal) mind-sets towards search capability leading to ‘fixes that fail’. The factors and mechanisms were identified in other industry organizations suggesting some theory generalizability. This is the first socio-technical analysis of Enterprise Search and Discovery capability. The findings challenge existing orthodoxy, such as the criticality of search literacy (agency) which has been neglected in the practitioner literature in favour of structure. The resulting multifactorial causal model and strategic framework for improvement present opportunities to update existing academic models in the IR, LIS and IS literature, such as the DeLone and McLean model for information system success. There are encouraging signs that Modality Theory may enable a reconfiguration of organizational mind-sets that could transform search task outcomes and ultimately business performance.

Diese kumulative Dissertation untersucht die Rolle mobiler Geräte im Informationsverhalten junger Kinder aus verschiedenen Perspektiven. Einerseits wird erforscht, ob informationsbezogene Aktivitäten Teil der Nutzung mobiler Technologien durch junge Kinder sind. Andererseits wird untersucht, ob Aspekte des kindlichen Informationsverhaltens bei der Sichtweise von Eltern und Kinder auf die Nutzung von mobilen Geräten eine Rolle spielen. Die erste in dieser Arbeit vorgestellte Studie bietet einen explorativen Einblick in die Nutzung mobiler Geräte durch junge Kinder anhand von Interviews mit Eltern von Kindern im Alter von ein bis sechs Jahren. Basierend auf einer Sekundäranalyse der Interviewdaten wird im Rahmen der zweiten Studie erforscht, wie Eltern die Nutzung von Mobilgeräten durch ihre Kinder wahrnehmen und medienpädagogisch begleiten und diskutiert, wie dies das Informationsverhalten der Kinder beeinflussen könnte. Unter Anwendung eines Uses-and-Gratifications-Ansatzes wird in der dritten Studie untersucht, was Kundenrezensionen für ein Kinder-Tablet über die Nutzung des Geräts und die Erwartungen von Familien aussagen. In der vierten Studie wird anhand eines multimethodischen Ansatzes ein besonderer Fokus auf die Einbeziehung der kindlichen Perspektive gelegt und erforscht, wie Kinder im Alter von vier bis sechs Jahren mobile Geräte nutzen und ob Aspekte des kindlichen Informationsverhaltens eine Rolle bei der Sichtweise von Familien auf die Nutzung spielen. Insgesamt zeigen die Ergebnisse, dass mobile Geräte definitiv eine Rolle im Informationsverhalten von jungen Kindern einnehmen können, wobei ihr Potenzial für die Entdeckung von Informationen oftmals nicht im Vordergrund der Wahrnehmung durch Eltern und Kinder steht. Mit diesen Erkenntnissen leistet die Arbeit einen wichtigen Beitrag zur Adressierung bestehender Forschungslücken im Bereich des Informationsverhaltens junger Kinder im Allgemeinen sowie im spezifischen Kontext der Nutzung mobiler Geräte. / This cumulative doctoral thesis examines the role of mobile devices in young children's information behavior from different perspectives. On the one hand, it explores whether information-related activities are part of young children's use of mobile technologies. On the other hand, it investigates whether aspects of children's information behavior play a role in parents' and children's perceptions of mobile device use. The first study presented in this thesis gains exploratory insight into young children's use of mobile devices through interviews with parents of families with children aged one to six years. Based on a secondary analysis of the interview data, the second study examines how parents perceive and mediate young children's use of mobile devices and discusses how this might influence children's information behavior. By applying a uses and gratifications approach, the third study investigates what customer reviews for a tablet for children reveal about the use of this device and expectations of the families. Using a multi-method approach, the fourth study places a particular focus on the inclusion of children's perspectives and investigates how children aged four to six years use mobile devices and whether aspects related to children's information behavior play a role in families' perceptions of this use. Overall, the results show that mobile devices can clearly play a role in young children's information behavior, although their potential for children's information discovery is not always prominent in parents' and children's perceptions. With these findings, this work makes an important contribution to addressing existing research gaps regarding young children's information behavior in general as well as in the specific context of mobile device use.