Differences between lexical features and orthographic features in NLP? -

features used model training , testing. differences between lexical features , orthographic features in natural language processing? examples preferred.

i not aware of such distinction, , of time when people talk lexical features talk using word itself, in contrast using other features, ie part-of-speech.

here example of paper means "whole word orthograph" when lexical features

one venture orthographic mean more abstract sequence of characters themselves, example whether sequence capitalized / titlecased / camelcased / etc. have useful , understood shape feature denomination that.

as such, recommend distinguishing features this:

lexical features: whole word, prefix/suffix (various lengths possible), stemmed word, lemmatized word

shape features: uppercase, titlecase, camelcase, lowercase

grammatical , syntactic features: pos, part of noun-phrase, head of verb phrase, complement of prepositional phrase, etc...

this not exhaustive list of possible features , feature categories, might categorizing linguistic features in clearer , more widely-accepted way.