Joy comes home from work exhausted and is surprised to find that her daughter, Michelle, has set the table and started dinner. Joy is thrilled. She praises Michelle and spends an extra half-hour reading with her before bed (something that Michelle likes). The same thing happens the next day, and soon this has become a daily event. This is an example of

Which of the following would be characteristic of trichotillomania?

a) hearing voices b) checking twice to make sure the door is locked c) repetitive hair pulling d) fear of heights

A classmate has missed class again and is copying your notes. Unfortunately, she can't figure out which research design uses each participant as his or her own control. Which should you tell her?

a. double-blind b. within-subjects c. between-subjects d. randomly assigned