In psychology, the social science concept of markedness is quantified as a measure of how much one variable is marked as a predictor or possible cause of another, and is also known as Δp (deltaP) in simple two-choice cases.
While the idea of linguistic asymmetry predated the actual coining of the terms marked and unmarked, the modern concept of markedness originated in the Prague School structuralism of Roman Jakobson and Nikolai Trubetzkoy as a means of characterizing binary oppositions.
Edwin Battistella wrote: "Binarism suggests symmetry and equivalence in linguistic analysis; markedness adds the idea of hierarchy.
[3] Forty years later, Jakobson described language by saying that "every single constituent of a linguistic system is built on an opposition of two logical contradictories: the presence of an attribute ('markedness') in contraposition to its absence ('unmarkedness').
Drawing on existing studies of acquisition and aphasia, Jakobson suggested a mirror-image relationship determined by a universal feature hierarchy of marked and unmarked oppositions.
Other semiotically-oriented work has investigated the isomorphism of form and meaning with less emphasis on invariance, including the efforts of Henning Andersen, Michael Shapiro, and Edwin Battistella.
Functional linguists such as Talmy Givón have suggested that markedness is related to cognitive complexity—"in terms of attention, mental effort or processing time".
[6] Linguistic 'naturalists' view markedness relations in terms of the ways in which extralinguistic principles of perceptibility and psychological efficiency determine what is natural in language.
[10] Battistella expanded this with the demonstration of how cultures align markedness values to create cohesive symbol systems, illustrating with examples based on Rodney Needham's work.
Joseph Greenberg's 1966 book Language Universals was an influential application of markedness to typological linguistics and a break from the tradition of Jakobson and Trubetzkoy.
What connects various approaches is a concern for the evaluation of linguistic structure, though the details of how markedness is determined and what its implications and diagnostics are varies widely.
Markedness entered generative linguistic theory through Noam Chomsky and Morris Halle's The Sound Pattern of English.
For Chomsky and Halle, phonological features went beyond a universal phonetic vocabulary to encompass an 'evaluation metric', a means of selecting the most highly valued adequate grammar.
However, Chomsky and Halle realized that their initial approach to phonological features made implausible rules and segment inventories as highly valued as natural ones.
Chomsky came to view unmarked properties as an innate preference structure based first in constraints and later in parameters of universal grammar.
An actual language is determined by fixing the parameters of core grammar and then adding rules or conditions, using much richer resources, ...