22,317 research outputs found
Explanation-Based Auditing
To comply with emerging privacy laws and regulations, it has become common
for applications like electronic health records systems (EHRs) to collect
access logs, which record each time a user (e.g., a hospital employee) accesses
a piece of sensitive data (e.g., a patient record). Using the access log, it is
easy to answer simple queries (e.g., Who accessed Alice's medical record?), but
this often does not provide enough information. In addition to learning who
accessed their medical records, patients will likely want to understand why
each access occurred. In this paper, we introduce the problem of generating
explanations for individual records in an access log. The problem is motivated
by user-centric auditing applications, and it also provides a novel approach to
misuse detection. We develop a framework for modeling explanations which is
based on a fundamental observation: For certain classes of databases, including
EHRs, the reason for most data accesses can be inferred from data stored
elsewhere in the database. For example, if Alice has an appointment with Dr.
Dave, this information is stored in the database, and it explains why Dr. Dave
looked at Alice's record. Large numbers of data accesses can be explained using
general forms called explanation templates. Rather than requiring an
administrator to manually specify explanation templates, we propose a set of
algorithms for automatically discovering frequent templates from the database
(i.e., those that explain a large number of accesses). We also propose
techniques for inferring collaborative user groups, which can be used to
enhance the quality of the discovered explanations. Finally, we have evaluated
our proposed techniques using an access log and data from the University of
Michigan Health System. Our results demonstrate that in practice we can provide
explanations for over 94% of data accesses in the log.Comment: VLDB201
Chemoinformatics Research at the University of Sheffield: A History and Citation Analysis
This paper reviews the work of the Chemoinformatics Research Group in the Department of Information Studies at the University of Sheffield, focusing particularly on the work carried out in the period 1985-2002. Four major research areas are discussed, these involving the development of methods for: substructure searching in databases of three-dimensional structures, including both rigid and flexible molecules; the representation and searching of the Markush structures that occur in chemical patents; similarity searching in databases of both two-dimensional and three-dimensional structures; and compound selection and the design of combinatorial libraries. An analysis of citations to 321 publications from the Group shows that it attracted a total of 3725 residual citations during the period 1980-2002. These citations appeared in 411 different journals, and involved 910 different citing organizations from 54 different countries, thus demonstrating the widespread impact of the Group's work
Contextualization of topics - browsing through terms, authors, journals and cluster allocations
This paper builds on an innovative Information Retrieval tool, Ariadne. The
tool has been developed as an interactive network visualization and browsing
tool for large-scale bibliographic databases. It basically allows to gain
insights into a topic by contextualizing a search query (Koopman et al., 2015).
In this paper, we apply the Ariadne tool to a far smaller dataset of 111,616
documents in astronomy and astrophysics. Labeled as the Berlin dataset, this
data have been used by several research teams to apply and later compare
different clustering algorithms. The quest for this team effort is how to
delineate topics. This paper contributes to this challenge in two different
ways. First, we produce one of the different cluster solution and second, we
use Ariadne (the method behind it, and the interface - called LittleAriadne) to
display cluster solutions of the different group members. By providing a tool
that allows the visual inspection of the similarity of article clusters
produced by different algorithms, we present a complementary approach to other
possible means of comparison. More particular, we discuss how we can - with
LittleAriadne - browse through the network of topical terms, authors, journals
and cluster solutions in the Berlin dataset and compare cluster solutions as
well as see their context.Comment: proceedings of the ISSI 2015 conference (accepted
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