Fundamentals of a graph transformation based web data processing system

Internet is the most complex and complete source of information in the history of mankind. The innumerable webpages and the myriads of data providers form a complex, highly heterogeneous, continuously evolving system. This environment demands continuous research of information retrieval. Here we present our contribution: a lightweight, semi-formal approach of web exploration and web data analysis. Our approach focuses on analyzing heterogeneous, semi- or barely structured web data. Complex queries can be performed over multiple heterogeneous data sources; graph transformations can be used to adjust the queries and to analyze the results. This approach integrates the a priori human knowledge, an effective web querying method, the formality of graph transformations and optionally qualitative and quantitative analysis algorithms. We present an illustrative case study performing multi-domain search and data transformations: Stack Overflow users are searched with high contribution in a topic, then the LinkedIn profiles of these users is tried to be matched.