Correlational finding on Happiness and subject: Hourly pay (vs salary)

StudyDeVoe & Pfeffer (2009): study US 2002
TitleWhen Is Happiness About How Much You Earn? The Effect of Hourly Payment on the Money-Happiness Connection.
SourcePersonality and Social Psychology Bulliten, 2009, Vol. 12, 1602 - 1618
DOIDOI:10.1177/0146167209346304
PublicWorking people, USA, 2002
SampleProbability stratified sample
Non-Response
Respondents N =15450

Correlate
Author's labelHourly status
Page in Source 1607
Our classificationHourly pay (vs salary)
Operationalization
Self report on single question:
In your main job, are you salaried, paid by the hour, 
of what?
0: salaried
1: paid by the hour
Observed distributionM = 0.62, SD=0.49

Observed Relation with Happiness
Happiness
Measure
StatisticsElaboration/Remarks
O-HL-c-sq-v-4-fr=-.10 p < .05
O-HL-c-sq-v-4-fBeta=-.02 ns
Beta controlled for:
- hourly status (salaried vs paid by the hour)
- occupation
- age
- gender
- education 
- marital status
- having children


Appendix 1: Happiness measures used
CodeFull Text
O-HL-c-sq-v-4-fSelfreport on single question:

If you were to consider your life in general these days, how happy or unhappy would you say you are, on the whole...?
4 very happy
3 fairly happy
2 not very happy
1 not at all happy


Appendix 2: Statistics used
SymbolExplanation
BetaSTANDARDIZED REGRESSION COEFFICIENT by LEAST SQUARES (OLS)
Type: test statistic.

Measurement level: Correlates: all metric, Happiness: metric.
Range: [-1 ; +1]

Meaning:
beta > 0 a higher correlate level corresponds to a higher happiness rating on average.
beta < 0 a higher correlate level corresponds to a higher happiness rating on average.
beta = 0 no correlation.
beta = + 1 or -1 perfect correlation.
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