What makes the sociolinguistics of sign language different from the sociolinguistics of spoken languages is that sign languages have several variables both internal and external to the language that are unique to the Deaf community.[3] Such variables include the audiological status of a signer's parents, age of acquisition, and educational background (home acquisition or residence schools).[3] There exist perceptions of socioeconomic status and variation of "grassroots" deaf people and middle-class deaf professionals, but this has not been studied in a systematic way.[3] "The sociolinguistic reality of these perceptions has yet to be explored".[3] Many variations in dialects correspond or reflect the values of particular identities of a community.