The following is an excerpt from a New York Times article; To Treat Depression. Drugs or Therapy by Richard Friedman. M.D. The article appeared on January 8th at 8 am. Dr. Helen Mayberg, a professor of psychiatry at Emory University, recently published a study in JAMA Psychiatry that identified a potential biomarker in the brain that could predict whether a depressed patient would respond better to psychotherapy or antidepressant medication. Using PET scans, she randomized a group of depressed patients to either 12 weeks of treatment with the S.S.R.I. antidepressant Lexapro or to cognitive behavior therapy, which teaches patients to correct their negative and distorted thinking. Over all, about 40 percent of the depressed subjects responded to either treatment. Is the value " 40 percent" a statistic or a parameter? statistic parameter