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This book constitutes the refereed proceedings of the 9th International Symposium on Search-Based Software Engineering, SSBSE 2017, held in Paderborn, Germany, in September 2017.
The 7 full papers and 5 short papers presented together with 4 challenge track and 2 students student track papers were carefully reviewed and selected from 26 submissions.
SSBSE welcomes not only applications from throughout the software engineering lifecycle but also a broad range of search methods
ranging from exact Operational Research techniques to nature-inspired algorithms and simulated annealing.

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Search-Based Software Engineering.- Software testing.- Automated Program Repair.- Software Evolution.- Combinatorial Testing.- Software Requirements Analysis.- Software Configuration.- Multi-Objective Optimization.- Evolutionary computation.- Software Diversity.- Mutation Testing.

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