Variable rules analysis is a set of
statistical analysis methods in linguistics that are commonly used in
sociolinguistics
Sociolinguistics is the descriptive study of the effect of any or all aspects of society, including cultural Norm (sociology), norms, expectations, and context (language use), context, on the way language is used, and society's effect on languag ...
and
historical linguistics
Historical linguistics, also termed diachronic linguistics, is the scientific study of language change over time. Principal concerns of historical linguistics include:
# to describe and account for observed changes in particular languages
# ...
to describe patterns of
variation between alternative forms in language use. It is also sometimes known as Varbrul analysis, after the name of a software package dedicated to carrying out the relevant statistical computations (''Varbrul'', from "variable rule"). The method goes back to a theoretical approach developed by the sociolinguist
William Labov
William Labov ( ; born December 4, 1927) is an American linguist widely regarded as the founder of the discipline of variationist sociolinguistics. He has been described as "an enormously original and influential figure who has created much of ...
in the late 1960s and early 1970s, and its mathematical implementation was developed by Henrietta Cedergren and
David Sankoff in 1974.
A variable rules analysis is designed to provide a quantitative model of a situation where speakers alternate between different forms that have the same meaning and stand in
free variation, but in such a way that the probability of choice of either the one or the other form is conditioned by a variety of context factors or social characteristics. Such a situation, where variation is not entirely random but rule-governed, is also known as "structured variation". A variable rules analysis computes a
multivariate
Multivariate may refer to:
In mathematics
* Multivariable calculus
* Multivariate function
* Multivariate polynomial
In computing
* Multivariate cryptography
* Multivariate division algorithm
* Multivariate interpolation
* Multivariate optical c ...
statistical model, on the basis of observed token counts, such that each determining factor is assigned a numerical factor weight that describes how it influences the probabilities of choice of either form. This is done by means of
stepwise logistic regression
In statistics, the logistic model (or logit model) is a statistical model that models the probability of an event taking place by having the log-odds for the event be a linear combination of one or more independent variables. In regression a ...
, using a
maximum likelihood
In statistics, maximum likelihood estimation (MLE) is a method of estimating the parameters of an assumed probability distribution, given some observed data. This is achieved by maximizing a likelihood function so that, under the assumed stat ...
algorithm.
Although the necessary computations required for a variable rules analysis can be carried out with the help of mainstream general-purpose statistics software packages such as
SPSS
SPSS Statistics is a statistical software suite developed by IBM for data management, advanced analytics, multivariate analysis, business intelligence, and criminal investigation. Long produced by SPSS Inc., it was acquired by IBM in 2009. C ...
, it is more often done by means of a specialised software dedicated to the needs of linguists, called ''Varbrul''. It was originally written by David Sankoff and currently exists in
freeware
Freeware is software, most often proprietary, that is distributed at no monetary cost to the end user. There is no agreed-upon set of rights, license, or EULA that defines ''freeware'' unambiguously; every publisher defines its own rules for t ...
implementations for
Mac OS
Two major famlies of Mac operating systems were developed by Apple Inc.
In 1984, Apple debuted the operating system that is now known as the "Classic" Mac OS with its release of the original Macintosh System Software. The system, rebranded "M ...
and
Microsoft Windows, under the title of ''Goldvarb X''. There are also versions implemented in the statistical language
R and therefore available on most platforms. These include ''R-Varb'' and ''Rbrul''.
Variable rules approaches are commonly employed for the analysis of data in sociolinguistic research, especially in studies that aim to investigate how reflexes of linguistic change through time appear in the shape of structured variation patterns within a speech community.
See also
*
Diaphoneme
A diaphoneme is an abstract phonological unit that identifies a correspondence between related sounds of two or more varieties of a language or language cluster. For example, some English varieties contrast the vowel of ''late'' () with that of ...
References
Linguistic research software
Logistic regression
Sociolinguistics
{{comp-ling-stub