Gallup 1976 studied attitudes toward nuclear energy over a

Gallup ( 1976) studied attitudes toward nuclear energy over a period of 10 years. The same individuals were interviewed in both 1965 and 1975, and during each inter-view, the respondents indicated their attitudes toward nuclear energy on a 5- point scale. The mean attitude scores were compared across interviews.

Solution

In this as the sample is used two times,

we must use paired t test for comparison of means.