Data science (aka Data mining)

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Mining of Massive Datasets

http://infolab.stanford.edu/~ullman/mmds.html
Visualization

Toolboxes

Datasets

Google Data Science tools

Data pre-processing and cleansing

http://code.google.com/p/oluolu/

oluolu - Project Hosting on Google Code

Oluolu is a open source query log mining tool which works on Hadoop.
http://www.clips.ua.ac.be/pages/pattern

Pattern | CLiPS

Pattern is a web mining module for the Python programming language. It bundles tools for data retrieval (Google + Twitter + Wikipedia API, web spider, HTML DOM parser), text analysis (rule-based shallow parser, WordNet interface, syntactical + semantical n-gram search algorithm, tf-idf + cosine similarity + LSA metrics), clustering and classification ( k -means, k -NN, SVM), and data visualization (graph networks).