1. CAS-IA System Description Jinhua Du CNGL July 23, 2008

2. Outline Hardware in IA Pre-process & Data MT System Configuration for Evaluation Achievements Conclusions

3. Hardware Machines Parallel Computing –Condor –Grid Computing Module developed by ASR group TypeOperating SystemNumberCPURAM Desktop PCWindows 20039Pentium 4, 3.0G2.0G ServerLinux (Ubuntu)1Xeon 2.0G×416.0G

4. Pre-process & Data Pre-processing –encoding conversion & filter –punctuation and number conversion (full-shaped -> half-shaped, etc.) –case conversion (only the initial alphabet of the initial word), abbreviation processing –Chinese word segment (ICT or IA tool), English tokenization Data for NIST –Parallel: 3.4 M (if adds UN corpus, up to 10M) –Monolingual: 3.4M + 9.6M(gigaword1&2) + 1.4M(giga3) = 14.4M Data for IWSLT –Parallel: BTEC(20K or 40K); LDC –Monolingual: BTEC; Gigaword –Data Filter: only need the high correlation data, very important for spoken evaluation (More better data, more better performance)

5. System Configuration Modules –Pre-processing –Alignment Post-preprocessing & Models Generation –Decoding & MER Training –System Combination & Post-Processing

6. Achievements (zh-en) The 3 rd MT Symposia in China ( rank 3) –Limited (830K pairs) –Unlimited (3M pairs)

7. Achievements (zh-en) NIST MT Eval. 2008 SystemBLEU-4IBM BLEU Primary （ combination ） 0.24070.2310 HPB0.24030.2279 STTB0.22860.2169 PB0.20000.1935

8. Achievements (zh-en) IWSLT2008 –More systems to be combined 2 PB systems developed by CASIA Moses SAMT (CMU) Hierarchical PB BTG-based system (Xiong) –Better performance (bleu+meteor)/ 2 bleumeteor (bleu+meteor)/ 2 bleumeteor 59.0949.8068.37tch.CRR58.7250.5566.89 58.2648.4468.08nlpr.CRR58.1249.3966.85

9. Conclusions More better data, better performance System combination is very helpful to improve the performance Evaluation is different from theoretical research: empirical methods and tricks are usually more effective For better rank, should be prepare in advance and build a temporarily team for evaluation Evaluation is a horrible thing for student: more time, more energy and no paper (joke but true) Develop systems for application purpose

10. Thanks