Earlier quoted context omitted.
Two points on this: (1) If you want to know how people feel, I’m afraid self-reports are the gold standard (2) Some other studies have large sample sizes (e.g. this one, which is based on my PhD: https://eprints.lse.ac.uk/49376/1/Mourato_Happiness_greater_... )
> If you want to know how people feel, I’m afraid self-reports are the gold standard "How people feel" can't directly be measured scientifically, but it is a function of many things, some of which can be measured reliably (weight, blood pressure, money, etc). I'd rather have a reliable measurement of quantity that I believe contributes to well-being than a direct measurement of well-being that I think is unreliable.…
Sometimes there's a difficult trade-off here, especially since (un)reliability isn't binary.
But a heavy prioritisation of reliability over direct measurement (which seems to be your position) is probably why governments have spent decades obsessing over GDP, which is a very poor wellbeing measure for all sorts of reasons.