The raw data

"The raw data may be anything: [...] It is the job of the parser to process the raw data and produce the following files". If the raw data really may be anything, then the parser must be able to parse anything. This is quite impossible.

<collection_name>.vocabulary

<word written in ASCII>: What to do with words that have non-ASCII chars in the input document?

Terms "word" and "non-word": Please give an exact definition.