Discriminative subgraphs are widely used to define the feature
space for graph classification in large graph databases. Several
scalable approaches have been proposed to mine discriminative
subgraphs. However, their intensive computation needs prevent
them from mining large databases. We propose an efficient
method GAIA for mining discriminative subgraphs for graph
classification in large databases. Our method employs a novel
subgraph encoding approach to support an arbitrary subgraph
pattern exploration order and explores the subgraph pattern space
in a process resembling biological evolution. In this manner,
GAIA is able to find discriminative subgraph patterns much faster
than other algorithms. Additionally, we take advantage of parallel
computing to further improve the quality of resulting patterns. In
the end, we employ sequential coverage to generate association
rules as graph classifiers using patterns mined by GAIA.
Extensive experiments have been performed to analyze the
performance of GAIA and to compare it with two other state-ofthe-art
approaches. GAIA outperforms the other approaches both
in terms of classification accuracy and runtime efficiency.