Those methods combine theoretical background (determining what it is that they measure) with defined set of questions and statistical processing of results.

Expert systems rely heavily on expert-constructed and organized knowledge bases, whereas many modern QA systems rely on statistical processing of a large, unstructured, natural language text corpus.

Those same machines had been used during World War II for cryptographic statistical processing.

For ease in statistical processing, categorical variables may be assigned numeric indices, e.g. 1 through K for a K-way categorical variable (i.e. a variable that can express exactly K possible values).

Hence statistical processing of language is once more an important technique used by computational linguists.

The first forms of graphism that allow one to hazardly identify an animal, did not appear until around 30,000 B.C. Prehistoric art records are very numerous, and statistical processing has allowed us to unravel the general meaning of what they represented.

Most notable amongst them are methods of database management and statistical processing.

Numerical data handling and elementary statistical processing (sum, avg, min, max)