Correlational finding on Happiness and subject: Current contacts

StudyKross et al. (2013): study US 2008
TitleFacebook Use Predicts Declines in Subjective Well-Being in Young Adults.
SourceOpen Access, 2013, Plos One, Vol. 8, 1 - 7
URLhttp://journals.plos.org/plosone/article?id=10.1371/journal.pone.0069841
DOIDOI: 10.1371/journal.pone.0069841
PublicFacebook users, Ann Arbor, Michigan, followed 14 days, USA, 2013
SampleNon-probability purposive sample
Non-Response
Respondents N =82

Correlate
Author's labelDirect contact
Page in Source Page 3
Our classificationCurrent contacts
Operationalization
Selfreport on single question text-beeped 5 times a 
day:
How much have you interacted with other people directly 
(= face to face or phone interactions) since the last 
time we asked?
Rated on a sliderscale ranging from
100  very positive
:
0 very negative
Observed distributionM = 35,74 SD = 31,11
Remarks
Experience Sampling Method (ESM)
Original rating scale ranged from 0 positive to 100 
negative and was reversed by WDH team

Observed Relation with Happiness
Happiness
Measure
StatisticsElaboration/Remarks
A-AOL-mi-sqr-ol-101-ar=+.28 p < .05


Appendix 1: Happiness measures used
CodeFull Text
A-AOL-mi-sqr-ol-101-aSelfreport on single question text messaged 5 times a day

How do you feel right now?
0 very positive
:
:
:
:
100 very negative


Appendix 2: Statistics used
SymbolExplanation
rPRODUCT-MOMENT CORRELATION COEFFICIENT (Also "Pearson's correlation coefficient' or simply 'correlation coefficient')
Type: test statistic.
Measurement level: Correlate: metric, Happiness: metric
Range: [-1; +1]

Meaning:
r = 0 no correlation ,
r = 1 perfect correlation, where high correlate values correspond with high happiness values, and
r = -1 perfect correlation, where high correlate values correspond with low happiness values.
Source:
Ruut Veenhoven, World Database of Happiness, Collection of Correlational Findings, Erasmus University Rotterdam.
https://worlddatabaseofhappiness.eur.nl