Ashley seems to fall asleep in the middle of a conversation. She has even suffered one of these sleep attacks while standing. She is likely to suffer from the sleep disturbance referred to as

In a correlational study, variables are studied a. as they exist naturally

b. after direct manipulation. c. during an experiment. d. at the population level.

Using an anonymous questionnaire to determine how many times students send or receive text messages during class is an example of using what modality of measurement?

a. self-report b. survey c. behavioral d. physiological