Which of the following statements are true?
a. A measurement is considered reliable only if it is valid.
b. A measure cannot be considered valid if it is not reliable.
c. Reliability refers to consistency of scores over time.
d. Test-retest reliability is high when scores on a test at time 1 are not correlated with test scores at time 2.
d. Split-half reliability is high if scores on the multiple choice and essay portions of a test correlate.
e. If two graduate students have similar scores for an observation of aggression in toddlers, then inter-rater reliability is low.