Findings on happiness in Robinson et al. (2001): study US 1986

Author(s)Robinson, J.L.; Corley, R.P.; Emde, R.N.
TitleDispositional Cheerfullness. Early Genetic and Environmental Influences.
SourceEmde, R.N.; Hewitt, J.K.: Eds.: ''Infancy to Early Childhood'', Oxford University Press, 2001, New York, USA, 163 - 177
PublicToddlers, same-sex twins, Colorado, United States, followed from 14 to 24 months of age, 1986-1989
Last assesment1989
Survey nameUnnamed study
 MacArthur Longitudinal Twin Study
SampleNon-probability purposive sample
 Twins chosen from the monthly reports of births of the Colorado Health Department; over 90% of sample is Caucasian, other patricipant group primarily Hispanic, 1% Black;
Respondents N =400
 100 monozygotic (MZ) twin pairs, 100 dizygotic (DZ) twin pairs;
Non ResponseNot available
AssesmentBehavioural observation
 behavioral observation at home and in laboratory, recorded on video tape; parental reports in questionnaire
Happiness measure(s) used
Full textTime sampling of happy behaviors during free play and Bayley testing. Analysis of 1 minute intervals during Bayley tests and 30 second intervals during free play Rated: 1 no positive emotion observed 2 positive interest 3 smiling 4 strong laughter Computation: average over all observations Interviewer rating of happiness, using flexible standards relative to the age of the subject. Full instructions not reported.
Author's labelPositive Hedonic Tone
Page in publication167-169
RemarksIn both test situations the Hedonic Tone Scale was used (Easterbrooks & Emde, 1983). Bayley Testing: lasts 40-45min, rating in 1-min intervals, sampled in 5-min blocks (i.e. 5min on, 5min, off) Free play: lasts 15min, rated continuously in 30sec intervals BAYLEY TEST: FREE PLAY: 14 months: M=2.41 sd=.33 N=393 M=2.23 sd=.27 N=394 20 months: M=2.44 sd=.31 N=367 M=2.30 sd=.28 N=369 24 months: M=2.50 sd=.34 N=354 M=2.25 sd=.22 N=354
Error estimatesCorreleations across contexts are relatively low at each age such that the reliability is not given. mean r=+.42
Finding used in
nation ranks
 On original range 1 - 4On range 0 - 10
Standard deviation0.29

Correlational findings

Author's labelSubject Code
Subject description
Empathy-positive expressionP05axEmpathic
Empathy-positive expressionP05ciPositive reacting, also classified as above ↑
Happiness of twin siblingH08ac04Happiness of sibblings
Happiness of twin siblingF01af02dHappiness of siblings, also classified as above ↑
Prohibition-positive hedonic toneP05akBold
Prohibition-positive hedonic toneP05ciPositive reacting, also classified as above ↑
Stability of positive hedonic tone across situationsH07ab02gA-CA by A-CA