Improving response rate How can we reduce the rate of refusals in telephone surveys? Most people who answer at all listen to the interviewer’s introductory remarks and then decide whether to continue. One study made telephone calls to randomly selected households to ask for opinions about the next election. In some calls, the interviewer gave her name, in others she identified the university she was representing, and in still others, she identified both herself and the university. For each type of call, the interviewer either did or did not offer to send a copy of the final survey results to the person interviewed. Do these differences in the introduction affect whether the interview is completed?

The experimental units, explanatory and response variables, and treatments must all be identified.

The treatments are randomly assigned to all of the experimental units in a completely randomized design.

In a double-blind experiment, neither the subjects nor the people who interact with them and assess the response variable are aware of the treatment they received.

Observational research looks at people and assesses factors of interest without trying to affect their responses.

Individuals are purposely subjected to a treatment in order to measure their responses in an experiment.

People picked at random as subjects.

Explanatory variables include interviewer information and whether the caller received survey findings.

Treatments include six different combinations of caller information and survey data. These are the six treatment areas:

1) There were no survey results offered by name or caller.

2) The university's identification and caller data did not provide.

3) There were no survey results listed by name, university, or beneficiary.

4) To submit the survey details, include the name and sender.

5) Caller's name and university for survey observations

6) The caller volunteered to submit the survey results by providing his or her name, university, and phone number.

Whether or not an interview was conducted is a response variable.