In this paper, we present a novel training method for a localized phrase-based prediction model for statistical machine translation (SMT). The model predicts block neighbors to carry out a phrasebased translation that explicitly handles local phrase re-ordering. We use a maximum likelihood criterion to train a log-linear block bigram model which uses real-valued features (e.g. a language model score) as well as binary features based on the block identities themselves (e.g. block bigram features). The model training relies on an efficient enumeration of local block neighbors in parallel training data. A novel stochastic gradient descent (SGD) training algorithm is presented that can easily handle millions of features. Moreover, when viewing SMT as a block generation process, it becomes quite similar to sequential natural language annotation problems such as part-of-speech tagging, phrase chunking, or shallow parsing. The novel approach is successfully tested on a standard Arabic-English translation task using two different phrase re-ordering models: a block orientation model and a phrase-distortion model. Categories and Subject Descriptors: I.2.7 [Artificial Intelligence]: Natural Language Processing—statistical machine translation; G.3 [Probability and Statistics]: Statistical computing— stochastic gradient descent

We propose a method for increasing word recognition accuracies by correcting the output of a handwriting recognition system. We treat the handwriting recognizer as a black-box, such that there is no access to its internals. This enables us to keep our algorithm general and independent of any particular system. We use a novel method for correcting the output based on a direct “phrase-based ” system in contrast to traditional sourcechannel models. We report the accuracies of an in-house handwritten word recognizer before and after the correction. We achieve highly encouraging results for a large dataset. 1

I thank the Almighty for providing me with this opportunity to serve Him and make a contribution through His infinite wisdom. I thank my parents for their perseverance and unconditional support, without which I could never have accomplished this endeavor. I would also like to thank other members of my family including my cousin Muneer who has been watching my back from day one. I want to extend my deep appreciation to Dr. Venu Govindaraju, the chair of my dissertation committee. He has been an advisor and a mentor. His persistent guidance, omnipresent motivation and overall support have been the foundation of this thesis. He introduced me to the area of handwriting recognition and encouraged me to address the open challenge of retrieval from handwritten documents. I want to show my gratitude to Dr. Peter Scott, member of my dissertation committee. His course Computer Vision and Image Processing indeed laid a solid foundation for iv this research. His guidance and advise has been always helpful. In addition, I had the opportunity to be his Teaching Assistant for three semesters and his passion for teaching was a great motivation.

The ever-increasing amount of parallel data opens a rich resource to multilingual natural language processing, enabling models to work on various translational aspects like detailed human annotations, syntax and semantics. With efficient statistical models, many cross-language applications have seen significant progresses in recent years, such as statistical machine trans-lation, speech-to-speech translation, cross-lingual information retrieval and bilingual lexicog-raphy. However, the current state-of-the-art statistical translation models rely heavily on the word-level mixture models — a bottleneck, which fails to represent the rich varieties and depen-dencies in translations. In contrast to word-based translations, phrase-based models are more robust in capturing various translation phenomena than the word-level (e.g., local word reordering), and less susceptive to the errors from preprocessing such as word segmentations and tok-enizations. Leveraging phrase level knowledge in translation models is challenging yet reward-ing: it also brings significant improvements on translation qualities. Above the phrase-level are

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