Twins who are produced when two separate ova are fertilized by two separate sperm at roughly the same time are called __________ twins

If you are using the correlation coefficient to describe the strength of linear association between X and Y in your sample, you must assume that the scores in the population from which the data were sampled are distributed as a bivariate normal distribution.

a. true b. false

Holly has recently entered therapy for a major depressive disorder at an important "down" period in her life

Her therapist suggests that she and Holly will work together to identify and change Holly's irrational thinking. After six weeks, Holly feels less depressed. Suppose, however, that the change resulted not from the therapy but rather from the normal "ups and downs" that people experience. This suggests that clinicians need to consider the impact of _____ on therapeutic outcomes. A) the placebo effect B) retrospective rewriting of the past C) self-serving biases D) spontaneous remission