In recent years there has been significant interest in evolutionary analysis of large-scale networks. Researchers study network evolution rate and mechanisms, the impact of specific events on evolution, and spatial and spatio-temporal patterns. To support data scientists who are studying network evolution, there is a need to develop scalable and generalizable systems. Tangible systems progress in turn depends on the availability of standardized datasets on which performance can be tested. In this work, we make progress towards a data generator for evolving property graphs, which represent evolution of graph topology, and of vertex and edge attributes. We propose an attribute-based model of preferential attachment, and instantiate this model on a co-authorship network derived from DBLP, with attributes representing publication venues of the authors. We show that this attribute-based model predicts which edges are created more accurately than a structure-only model. Finally, we demonstrate that synthetic graphs are indeed useful for evaluating performance of evolving graph query primitives.
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Zooming Out on an Evolving Graph
An evolving graph maintains the history of changes of graph topology and attribute values over time. Such a graph has a specific temporal and structural resolution. It is often useful to modify this resolution during analysis, for example, to consider communities rather than individual nodes, or to quantify changes at the level of days rather than hours. We propose attribute-based zoom and temporal window-based zoom -- two operators that support exploratory analysis of an evolving graph at different levels of resolution. We develop several alternative physical representations of an evolving property graph -- a temporal generalization of a property graph --- and detail how to implement the proposed zoom operators using dataflow operations. These different physical representations allow us to explore the trade-offs in temporal and structural locality with respect to the performance of the zoom operators. We implement the operators in Apache Spark, evaluate them on real evolving graph datasets, and demonstrate scalability to billion-edge graphs.
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- Award ID(s):
- 1916505
- PAR ID:
- 10137087
- Date Published:
- Journal Name:
- Proceedings of the 23rd International Conference on Extending Database Technology (EDBT)
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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