Differences according to class
Further information: Linguistic insecurity
Sociolinguistics as a field distinct from dialectology was pioneered through the study of language variation in urban areas. Whereas dialectology studies the geographic distribution of language variation, sociolinguistics focuses on other sources of variation, among them class. Class and occupation are among the most important linguistic markers found in society. One of the fundamental findings of sociolinguistics, which has been hard to disprove, is that class and language variety are related. Members of the working class tend to speak less standard language, while the lower, middle, and upper middle class will in turn speak closer to the standard. However, the upper class, even members of the upper middle class, may often speak 'less' standard than the middle class.The looseness or tightness of a social network may affect speech patterns adopted by a speaker. For instance, Sylvie Dubois and Barbara Horvath found that speakers in one Cajun Louisiana community were more likely to pronounce English "th" [θ] as [t] (or [ð] as [d]) if they participated in a relatively dense social network (i.e. had strong local ties and interacted with many other speakers in the community), and less likely if their networks were looser (i.e. fewer local ties) This is because not only class, but class aspirations, are important.
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