2940771
Graph indexing: a frequent structure-based approach
Graph has become increasingly important in modelling complicated structures and schemaless data such as proteins, chemical compounds, and XML documents. Given a graph query, it is desirable to retrieve graphs quickly from a large database via graph-based indices. In this paper, we investigate the issues of indexing graphs and propose a novel solution by applying a graph mining technique. Different from the existing path-based methods, our approach, called gIndex, makes use of frequent substructure as the basic indexing feature. Frequent substructures are ideal candidates since they explore the intrinsic characteristics of the data and are relatively stable to database updates. To reduce the size of index structure, two techniques, size-increasing support constraint and discriminative fragments, are introduced. Our performance study shows that gIndex has 10 times smaller index size, but achieves 3--10 times better performance in comparison with a typical path-based method, GraphGrep. The gIndex approach not only provides and elegant solution to the graph indexing problem, but also demonstrates how database indexing and query processing can benefit form data mining, especially frequent pattern mining. Furthermore, the concepts developed here can be applied to indexing sequences, trees, and other complicated structures as well.
21192
Mining Frequent Patterns without Candidate Generation: A Frequent-Pattern Tree Approach
Mining frequent patterns in transaction databases, time-series databases, and many other kinds of databases has been studied popularly in data mining research. Most of the previous studies adopt an Apriori-like candidate set generation-and-test approach. However, candidate set generation is still costly, especially when there exist a large number of patterns and/or long patterns.In this study, we propose a novel frequent-pattern tree (FP-tree) structure, which is an extended prefix-tree structure for storing compressed, crucial information about frequent patterns, and develop an efficient FP-tree-based mining method, FP-growth, for mining the complete set of frequent patterns by pattern fragment growth. Efficiency of mining is achieved with three techniques: (1) a large database is compressed into a condensed, smaller data structure, FP-tree which avoids costly, repeated database scans, (2) our FP-tree-based mining adopts a pattern-fragment growth method to avoid the costly generation of a large number of candidate sets, and (3) a partitioning-based, divide-and-conquer method is used to decompose the mining task into a set of smaller tasks for mining confined patterns in conditional databases, which dramatically reduces the search space. Our performance study shows that the FP-growth method is efficient and scalable for mining both long and short frequent patterns, and is about an order of magnitude faster than the Apriori algorithm and also faster than some recently reported new frequent-pattern mining methods.
43532686
AIM: Approximate Intelligent Matching for Time Series Data
Time-series data mining presents many challenges due to the intrinsic large scale and high dimensionality of the data sets. Subsequence similarity matching has been an active research area driven by the need to analyse large data sets in the financial, biomedical and scientific databases. In this paper, we investigate an intelligent subsequence similarity matching of time series queries based on efficient graph traversal. We introduce a new problem, the approximate partial matching of a query sequence in a time series database. Our system can address such queries with high specificity and minimal time and space overhead. The performance bottleneck of the current methods were analysed and we show our method can improve the performance of the time series queries significantly. It is general and flexible enough to find the best approximate match query without specifying a tolerance Ɛ parameter.
10015971
Predicting Change Impact in Architecture Design with Bayesian Belief Networks
Research into design rationale in the past has focused on the representation of reasons and has omitted the connections between design rationales and design artefacts. Without such connections, designers and architects cannot easily assess how changing requirements or designs may affect the system. In this paper, we introduce a model called Architecture Rationale and Element Linkage (AREL) to represent the causal relationship between architecture elements and decisions. We further model AREL as a Bayesian Belief Network (BBN) to capture the probabilistic relationships between architecture elements and decisions in an architecture design model. Such probabilistic modelling enables architects to quantitatively predict and diagnose impact of change when part of the requirements or designs are changing. Using a partial design of a cheque image processing system, we illustrate how AREL is used to represent the decision model and how BBN is used to predict and diagnose change in the architecture design. We use a UML tool to capture the AREL model and a BBN tool to compute the probabilities of change impact.
16459038
Efficient Mining of Intertransaction Association Rules
Most of the previous studies on mining association rules are on mining intratransaction associations, i.e., the associations among items within the same transaction. We extend the scope to include multidimensional, intertransaction associations. In a database of stock price information, an example of such an association is "if (company) A's stock goes up on day one, B's stock will go down on day two but go up on day four:" whether we treat company or day as the unit of transaction, the items belong to different transactions. Moreover, such an intertransaction association can be extended to associate multiple properties in the same rule, so that multidimensional intertransaction associations can also be defined and discovered. Mining intertransaction associations pose more challenges on efficient processing than mining intratransaction associations because the number of potential association rules is extremely large. We introduce the notion of intertransaction association rule and develop an efficient algorithm, FITI (first intra then inter), for mining intertransaction associations, which adopts two major ideas: 1) an intertransaction frequent itemset contains only the frequent itemsets of its corresponding intratransaction counterpart; and 2) a special data structure is built among intratransaction frequent itemsets for efficient mining of intertransaction frequent itemsets.
52184467
International workshop on service oriented software engineering (IW-SOSE'06)
International workshop on service oriented software engineering (IW-SOSE'06) : In Proceeding of the 28th international Conference on Software Engineering (Shanghai, China, May 20 - 28, 2006). ICSE '06.
29673478
Exploring the Power of Links in Data Mining
Algorithms like PageRank and HITS have been developed in late 1990s to explore links among Web pages to discover authoritative pages and hubs. Links have also been popularly used in citation analysis and social network analysis. We show that the power of links can be explored thoroughly in data mining, such as classification, clustering, information integration, and object distinction. Some recent results of our research that explore the crucial information hidden inside links will be introduced, including (1) multi-relational classification, (2) user-guided clustering, (3) link-based clustering, and (4) object distinction analysis. The power of links in other analysis tasks will also be discussed in the talk.
14721307
Specifying Interaction Constraints of Software Components for Better Understandability and Interoperability
A vital issue in the correct use of commercial-off-the-shelf (COTS) components is the proper understanding of their functionality, quality attributes and ways of operation. Traditionally, COTS component vendors provide some of this information in accompanying documentation. However, the documentation is often informal and likely contains ambiguous and inconsistent statements. Even equipped with interface descriptions clearly defining the basic aspects of component use, such as operation signatures and operating platforms, this documentation does not provide a mathematically sound means for addressing the behavioural interoperability issues in component-based system design. In this paper, we propose a formal but user-friendly component specification approach which augments commercial IDLs with the capability of capturing component interoperability requirements. This approach uses unambiguous temporal operators to define sequencing and concurrency constraints between component operation invocations. Accordingly, it enables precise specifications of how a component provides its services and the correct way in which its services should be used.