Variable rules analysis is a set of

statistical analysis Statistical inference is the process of using data analysis to infer properties of an underlying probability distribution.Upton, G., Cook, I. (2008) ''Oxford Dictionary of Statistics'', OUP. . Inferential statistical analysis infers properties of ...

methods in linguistics that are commonly used in

sociolinguistics Sociolinguistics is the descriptive, scientific study of how language is shaped by, and used differently within, any given society. The field largely looks at how a language changes between distinct social groups, as well as how it varies unde ...

and

historical linguistics Historical linguistics, also known as diachronic linguistics, is the scientific study of how languages change over time. It seeks to understand the nature and causes of linguistic change and to trace the evolution of languages. Historical li ...

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 David Labov ( ; December4, 1927December17, 2024) was 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 ...

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 In linguistics, free variation is the phenomenon of two (or more) sounds or forms appearing in the same environment without a change in meaning and without being considered incorrect by native speakers. Sociolinguists argue that describing such ...

, 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" or "orderly heterogeneity". A variable rules analysis computes a multivariate 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, a logistic model (or logit model) is a statistical model that models the logit, log-odds of an event as a linear function (calculus), linear combination of one or more independent variables. In regression analysis, logistic regres ...

, 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 stati ...

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. Versi ...

, 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, 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 the free ...

implementations for

Mac OS Mac operating systems were developed by Apple Inc. in a succession of two major series. 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 ...

and

Microsoft Windows Windows is a Product lining, product line of Proprietary software, proprietary graphical user interface, graphical operating systems developed and marketed by Microsoft. It is grouped into families and subfamilies that cater to particular sec ...

, 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.

References

Linguistic research software Logistic regression Sociolinguistics {{comp-ling-stub

See also

References