A recent report concluded that children with siblings have better social skills than children who grow up as an only child. This is an example of an experimental study

Your textbook suggests that there is a great irony involved in research on schizophrenia, noting that

a. the original physician who developed the diagnostic category was later diagnosed with schizophrenia himself. b. for over 100 years, we have known that the diagnostic category we now recognize as schizophrenia may well be composed of many different kinds of mental disorders. c. we have had a clear model of the cause of schizophrenia for over 100 years, but we have still not identified an effective treatment. d. schizophrenia is really another name for bipolar disorder.

The sign of a z score indicates whether the individual raw score is larger or smaller than its

a. mode. b. median. c. mean. d. standard deviation.