We present an annotation management system for relational databases. In this system, every piece of data in a relation is assumed to have zero or more annotations associated with it and annotations are propagated along, from the source to the output, as data is being transformed through a query. Such an annotation management system is important for understanding the provenance and quality of data, especially in applications that deal with integration of scientific and biological data. We present an extension, pSQL, of a fragment of SQL that has three different types of annotation propagation schemes, each useful for different purposes. The default scheme propagates annotations according to where data is copied from. The default-all scheme propagates annotations according to where data is copied from among all equivalent formulations of a given query. The custom scheme allows a user to specify how annotations should propagate. We present a storage scheme for the annotations and describe algorithms for translating a pSQL query under each propagation scheme into one or more SQL queries that would correctly retrieve the relevant annotations according to the specified propagation scheme. For the default-all scheme, we also show how we generate finitely many queries that can simulate the annotation propagation behavior of the set of all equivalent queries, which is possibly infinite. The algorithms are implemented and the feasibility of the system is demonstrated by a set of experiments that we have conducted. 1

With bookmark programs, current Web browsers provide a limited support to personalize the Web. We present a new Web annotation tool which uses the Document Object Model Level 2 and Dynamic HTML to deliver a system where speed and privacy are important issues. We report on several experiments showing how annotations improve document access and retrieval by providing user-directed document summaries. Preliminary results also show that annotations can be used to produce user-directed document clustering and classification. Introduction Current Web browsers provide a limited support to personalize the Web, namely bookmarks. In two recent surveys, users report that the use of bookmarks is among the three main problems they have when using the Internet (Abrams, 1998 ; Cockburn, 1999). We see several problems when using bookmarks : The number of bookmarks grows linearly with time (Abrams, 1998) and it becomes a real challenge for many users to organize this amount of data By storing the...

Increasingly, documents exist primarily in digital form. System designers have recently focused on making it easier to read digital documents, with annotation as an important new feature. But supporting annotation well is difficult because digital documents are frequently modified, making it challenging to correctly reposition annotations in modified versions. Few systems have addressed this issue, and even fewer have approached the problem from the users' point of view. This paper reports the results of two studies examining user expectations for "robust" annotation positioning in modified documents. We explore how users react to lost annotations, the relationship between types of document modifications and user expectations, and whether users pay attention to text surrounding their annotations. Our results could contribute substantially to effective digital document annotation systems. Keywords Annotation, robust, digital, documents, annotation system design. 1 INTRODUCTION Four ...

Multimedia content is a central component of ondemand training and education delivered over the World Wide Web. Supporting asynchronous collaboration around educational multimedia is a key requirement for making the online educational environment effective. A multimedia annotation system tightly integrated with email provides a powerful platform on which to base such functionality. Building on our earlier work with multimedia annotations [3], we present user interface and system extensions to support asynchronous collaboration for on-demand training. We report results from a study of the effectiveness of the system, including student experience, instructor experience, and user interface appropriateness. Overall, the student experience was positive: they appreciated the flexibility of on-demand delivery and benefited from the collaborative features.

Streaming video on the World Wide Web is being widely deployed, and workplace training and distance education are key applications. The ability to annotate video on the Web can provide significant added value in these and other areas. Written and spoken annotations can provide “in context ” personal notes and can enable asynchronous collaboration among groups of users. With annotations, users are no longer limited to viewing content passively on the web, but are free to add and share commentary and links, thus transforming the web into an interactive medium. We discuss design considerations in constructing a collaborative video annotation system, and we introduce our prototype, called MRAS. We present preliminary data on the use of Web-based annotations for personal note-taking and for sharing notes in a distance education scenario. Users showed a strong preference for MRAS over pen-andpaper for taking notes, despite taking longer to do so. They also indicated that they would make more comments and questions with MRAS than in a “live ” situation, and that sharing added substantial value.

We study the problem of determining whether a query is contained in another when queries can carry along annotations from source data. We say that a query is annotation-contained in another if the annotated output of the former is contained in the latter on every possible annotated input databases. We study the relationship between query containment and annotation-containment and show that annotation-containment is a more refined notion in general. As a consequence, the usual equivalences used by a typical query optimizer may no longer hold when queries can carry along annotations from the source to the output. Despite this, we show that the same annotated result is obtained whether intermediate constructs of a query are evaluated with set or bag semantics. We also give a necessary and sufficient condition, via homomorphisms, that checks whether a query is annotationcontained in another. Even though our characterization suggests that annotation-containment is more complex than query containment, we show that the annotation-containment problem is NP-complete, thus putting it in the same complexity class as query containment. In addition, we show that the annotation placement problem, which was first shown to be NP-hard in [BKT02], is in fact DP-hard and the exact complexity of this problem still remains open.

Annotations are a natural way to record comments and ideas in specific contexts within a document. When people read, they often underline important parts of a document or write notes in the margin. While we typically think of annotating paper documents, systems that support annotating digital documents are becoming increasingly common. Annotations on digital documents are easily shared among groups of people, making them valuable for a wide variety of tasks, including online discussion and providing feedback. This research explores three issues that arise when using annotations for asynchronous collaboration. First, I present the results of using a prototype annotation system, WebAnn, to support online discussions in an educational setting. In a field study in a graduate class, students contributed twice as much content to the discussion using annotations compared to a traditional bulletin board. Annotations also encouraged a different discussion style that focused on specific points in the paper being discussed. The study results suggest valuable improvements to the annotation system and factors to consider when incorporating online discussion into a class. Second, I examine providing appropriate notification mechanisms to support online discussion using annotations. After studying notifications in a large-scale commercial system and finding them lacking, I designed and deployed enhancements to the system. A field study of the new notifications found that overall awareness of annotation activity on software specifications increased with my enhancements. The study also found that providing more information in notification messages, supporting multiple communication channels through which notifications can be received, and allowing customization of notification messages ...

Annotating resources on the World Wide Web in a flexible manner is a key problem, yet there is no standard for annotations on the Web. We propose a design for CAF, a Common Annotation Framework that supports annotation across applications in a standard way. The framework is based on a principled logical model, and is designed to meet a wide set of annotation needs without overburdening any particular application with excessive functionality. It is flexible and extensible, and can support annotation of any media type with any media type. We discuss the structure and function of the CAF logical model, and we describe a proposed CAF schema. We explain how CAF can be extended and give examples. And we present a web-based annotation application built using CAF.

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A group of individuals who share the same interest or a task, would profit from making use of the knowledge possessed by the group. It is then essential that such a body of knowledge, or "community knowledge", be captured in an effective manner. This paper describes the notion of Concept Index, which aims to index important concepts described in a collection of documents belonging to a group, and provide user-friendly cross-references among them to aid concept-oriented document space navigation. Unlike approaches relying primarily on automatic concept extraction tools, the Concept Index relies on users in identifying important concepts by marking keywords and phrases that interest them. Once the concepts are extracted in this manner, they are then enhanced by automated tools and more importantly by users who inspect them. We argue that with an appropriate support for users provided by a system, this interactive process optimises the index generated, and enhances collaboration between t...