Figure:
A researcher was interested in developing a reliable and valid measure of friendliness.That is,she wanted to distinguish between friendly and unfriendly people using her questionnaire.To determine whether she developed a good measure (called "Friend"),she administered her "Friend" questionnaire to a group of 300 people twice (Friend-Time1 and Friend-Time 2),separated by six months.At the second testing session she also administered a similar questionnaire called "Nice," which previous research has shown to be a valid measure of people's ability to get along with people and to make friends.She also administered a questionnaire designed to measure art ability,which she predicted to be unrelated to friendliness.She observed the following correlations among the measures:
-What correlation coefficient value indicates the "Friend" measure is reliable?

Question

Figure:
A researcher was interested in developing a reliable and valid measure of friendliness.That is,she wanted to distinguish between friendly and unfriendly people using her questionnaire.To determine whether she developed a good measure (called "Friend"),she administered her "Friend" questionnaire to a group of 300 people twice (Friend-Time1 and Friend-Time 2),separated by six months.At the second testing session she also administered a similar questionnaire called "Nice," which previous research has shown to be a valid measure of people's ability to get along with people and to make friends.She also administered a questionnaire designed to measure art ability,which she predicted to be unrelated to friendliness.She observed the following correlations among the measures: 
-What correlation coefficient value indicates the "Friend" measure is reliable?

Quizplus · Accepted Answer

The Answer is The test-retest reliability is .85.

Figure: A Researcher Was Interested in Developing a Reliable and Valid