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-Time 1 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?
What correlation coefficient value indicates the "Friend" measure has good convergent validity?
What correlation coefficient value indicates the "Friend" measure has good discriminant validity?
Is the researcher able to conclude that she has developed a reliable and valid measure of friendliness?
