Study Bachman et al. (1978): study US 1966 /1
- Public
 - Public highschool boys followed 8 years from grade 10, USA, 1966-74
 - Sample
 - Respondents
 - N = 2213
 - Non Response
 - 2.8% at T1, 17.2% at T2, 21.0% at T3, 28.9% at T4, 28.5% at T5
 - Assessment
 - 
        Interview: face-to-face                    
Interviews, tests and questionnaires 
Correlate
- Authors's Label
 - Concern about overpopulation
 - Our Classification
 - 
            
 - 
                        
 - Operationalization
 - A mean of 6 items measuring respondent 's concern about overpopulation and his perception of what an ideal population size would be for the U.S. and for the world. Scale: 1.00 = low to 5.00 = high concern about overpopulation. Assessed at T4 and T5
 
Observed Relation with Happiness
Happiness T4 T5
T1 tau = -.04 -.00
T2 tau = -.01 -.01
T3 tau = -.02 -.02
T4 tau = -.02 -.01
All tau's not significant
T1:1966, T2:1968, T3:1969, T4:1970, T5:1974