- College students, psychology course, USA, 1934-35
- N = 180
- Non Response
Questionnaire: Paper & Pencil Interview (PAPI)
Filled out twice with an interval of 16 days.
- Authors's Label
- Frequency of laughing
- Our Classification
- Repeated open-ended question on number of occasions one laughed during the past 24 hours; scored twice with an in- terval of 16 days.