A sample of n = 9 scores has a variance of s2= 36 . What is the estimated standard error for the sample mean?

All of the following might be reasons to use parental reports instead of researchers' measures except

a. parents have a wider range of experience observing their infants b. parents tend to be more objective about their infants' behavior c. parents are unlikely to elicit wariness or unusual behavior in their infants d. parents can be trained to keep diaries about their infants' development, noting when a particular behavioral milestone is achieved

The idea that individuals who are biologically vulnerable to depression place themselves in high-risk, stressful environments reflects the a. Self-fulfilling prophecy theory

b. cognitive-behavioral model. c. reciprocal gene-environment model. d. stress-depression linkage effect.