Writer invariant, also called authorial invariant or author's invariant, is a property of a text which is invariant of its

author An author is the writer of a book, article, play, mostly written work. A broader definition of the word "author" states: "''An author is "the person who originated or gave existence to anything" and whose authorship determines responsibility f ...

, that is, it will be similar in all texts of a given author and different in texts of different authors. It can be used to find

plagiarism Plagiarism is the fraudulent representation of another person's language, thoughts, ideas, or expressions as one's own original work.From the 1995 '' Random House Compact Unabridged Dictionary'': use or close imitation of the language and though ...

or discover who is real author of

anonymously Anonymity describes situations where the acting person's identity is unknown. Some writers have argued that namelessness, though technically correct, does not capture what is more centrally at stake in contexts of anonymity. The important idea he ...

published text. Writer invariant is also an author's pattern of writing a letter in

handwritten Handwriting is the writing done with a writing instrument, such as a pen or pencil, in the hand. Handwriting includes both printing and cursive styles and is separate from formal calligraphy or typeface. Because each person's handwriting is u ...

text recognition. While it is generally recognised that writer invariants exist, it is not agreed what properties of a text should be used. Among the first ones used was distribution of

word A word is a basic element of language that carries an objective or practical meaning, can be used on its own, and is uninterruptible. Despite the fact that language speakers often have an intuitive grasp of what a word is, there is no consen ...

lengths; other proposed invariants include average sentence length, average word length,

noun A noun () is a word that generally functions as the name of a specific object or set of objects, such as living creatures, places, actions, qualities, states of existence, or ideas.Example nouns for: * Organism, Living creatures (including people ...

verb A verb () is a word ( part of speech) that in syntax generally conveys an action (''bring'', ''read'', ''walk'', ''run'', ''learn''), an occurrence (''happen'', ''become''), or a state of being (''be'', ''exist'', ''stand''). In the usual descr ...

adjective In linguistics, an adjective ( abbreviated ) is a word that generally modifies a noun or noun phrase or describes its referent. Its semantic role is to change information given by the noun. Traditionally, adjectives were considered one of the ...

usage frequency,

vocabulary A vocabulary is a set of familiar words within a person's language. A vocabulary, usually developed with age, serves as a useful and fundamental tool for communication and acquiring knowledge. Acquiring an extensive vocabulary is one of the la ...

richness, and frequency of

function word In linguistics, function words (also called functors) are words that have little lexical meaning or have ambiguous meaning and express grammatical relationships among other words within a sentence, or specify the attitude or mood of the speaker ...

s, or specific function words. Of these, average sentence lengths can be very similar in works of different authors or vary significantly even within a single work; average word lengths likewise turn out to be very similar in works of different authors. Analysis of function words shows promise because they are used by authors unconsciously.

References

Statistical natural language processing {{comp-ling-stub

See also

References