Car dealership statistics question

Telephone interviews often allow more inexpensive data collection, improve the completeness of the data records collected, and are usually characterized by higher response rates.

In a self-administered survey, such as a mail-in survey, respondents control the survey pace and are able to see all of the questions and response options on the screen or paper.

Because of these differences, when respondents answer questions that an interviewer reads aloud to them, research has consistently shown that respondents tend to give more extreme, positive responses to attitudinal items and more socially desirable responses than when the same questions are administered to the same population via web or mail.

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