What are the distinctions between surveys and interviews, and what are the benefits and difficulties of each?

Answer 1

Try this page and accompanying ones at this site.

Answer 2

The most characteristic difference between a survey and an interview is the method of questioning. In surveys, large number of people are asked to fill up a pre planned questionaire.
In interviews, each individual is personally questioned, either face to face, or other media like phone and internet.

Surveys provide anonymity.
The individual can answer questions freely, as he doesn't feel the need to hide actual responses because of guilt shame or privacy.
Surveys can be done over a large sextion of people, cheaply and easily.
It is less time consuming

Interviews provide a personal touch.
The interviewer can gauge the non verbal (facial, posture) responses to the questions asked.
The interviewer can also conduct an unstructured interview. In such an interview the questions are changed,modifiied or added according to the answers given. In depth information can be obtained.
Also, interviews leaves enough scope for explanation of unclear or ambiguous questions.

Answer 3

An interview is done person to person it could be structured or unstructured. A structured interview gives better reliability however some people may not answerer honestly because they are embarrassed. Or they may answer in a way they believe the interviewer is looking for. A survey has limitations because people only answer the questions on it and you cannot add others as you see fit. However people are more likely to answer honestly because of the anonymity surveys provide.