Type: test statistic
Measurement level: Correlate: metric, Happiness: metric
Range:  [-1; +1]
Meaning:  a partial correlation between happiness and one of the correlates is that correlation, which remains after accounting for the contribution of the other influences, or some of them, to the total variability in the happiness scores. 
Under that conditions 
rpc > 0  « a higher correlate level corresponds with  a higher  happiness rating,
rpc < 0  «  a higher correlate level corresponds with  a lower  happiness rating,