Billions of dollars are spent annually on software-related cost. It is estimated that up to 45 percent of software cost is due to the difficulty in understanding existing systems when performing maintenance tasks (i.e., adding features, removing bugs, etc.). One of the root causes is that software products often come with poor, incomplete, or even […]
Efficient Periodicity Mining in Time Series Databases Using Suffix Trees
Periodic pattern mining or periodicity detection has a number of applications, such as prediction, forecasting, detection of unusual activities, etc. The problem is not trivial because the data to be analyzed are mostly noisy and different periodicity types (namely symbol, sequence, and segment) are to be investigated. Accordingly, we argue that there is a need […]
Automatic discovery of personal name aliases from the web
An individual is typically referred by numerous name aliases on the web. Accurate identification of aliases of a given person name is useful in various web related tasks such as information retrieval, sentiment analysis, personal name disambiguation, and relation extraction. We propose a method to extract aliases of a given personal name from the web. […]
A Link Analysis Extension of Correspondence Analysis for Mining Relational Databases
This work introduces a link analysis procedure for discovering relationships in a relational database or a graph, generalizing both simple and multiple correspondence analysis. It is based on a random walk model through the database defining a Markov chain having as many states as elements in the database. Suppose we are interested in analyzing the […]
Exploring Application-Level Semantics for Data Compression
Natural phenomena show that many creatures form large social groups and move in regular patterns. However, previous works focus on finding the movement patterns of each single object or all objects. In this paper, we first propose an efficient distributed mining algorithm to jointly identify a group of moving objects and discover their movement patterns […]
On the Complexity of View Update Analysis and its Application to Annotation Propagation
This paper investigates three problems identified by Buneman et al. for annotation propagation, namely, the view side-effect, source side-effect and annotation placement problems. Given annotations entered for a tuple or an attribute in a view, these problems ask what tuples or attributes in the source have to be annotated to produce the view annotations. As […]
Optimal Service Pricing for a Cloud Cache
Cloud applications that offer data management services are emerging. Such clouds support caching of data in order to provide quality query services. The users can query the cloud data, paying the price for the infrastructure they use. Cloud management necessitates an economy that manages the service of multiple users in an efficient, but also, resource-economic […]
Publishing Search Logs – A Comparative Study of Privacy Guarantees
Search engine companies collect the “database of intentions,” the histories of their users’ search queries. These search logs are a gold mine for researchers. Search engine companies, however, are wary of publishing search logs in order not to disclose sensitive information. In this paper we analyze algorithms for publishing frequent keywords, queries and clicks of […]
Scalable Scheduling of Updates in Streaming Data Warehouses
We discuss update scheduling in streaming data warehouses, which combine the features of traditional data warehouses and data stream systems. In our setting, external sources push append-only data streams into the warehouse with a wide range of inter-arrival times. While traditional data warehouses are typically refreshed during downtimes, streaming warehouses update base tables and layers […]
Horizontal Aggregations in SQL to Prepare Data Sets for Data Mining Analysis
Preparing a data set for analysis is generally the most time consuming task in a data mining project, requiring many complex SQL queries, joining tables and aggregating columns. Existing SQL aggregations have limitations to prepare data sets because they return one column per aggregated group. In general, a significant manual effort is required to build […]