From the provided question by WHR I can definitely see how Scandinavian countries rank so high. Being Danish myself my answer would immediately go into long term thinking and whether I would have a better life elsewhere and to me the answer is a clear no. Not financially, socially or politically. So yes, Denmark scores really high, but is it really measuring happiness. I dont know. That said I dont think measuring how often we laugh as a better metric amongst other thing, I can be perfectly "happy" without being outwardly joyous, maybe contentment is a better word. Or well being. But it isn't as catchy i guess