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1) use case examples for the HTRC feature extraction functionality, available in a Google doc here https://docs.google.com/document/d/14-be-4VBNeVPZsFO-e7UWephgf71LfYvhlr9qssEfTg/edit (document prepared by Sayan Bhattacharyya)
2) challenges presented to HTRC text mining, or more broadly, historical text: scalability, curse of dimensionality, plus OCR errors.
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