This is the great part about science: whether or not you agree with the authors' conclusions, they just asked the question "is our preconceived 'obviously correct' conclusion actually correct". Then, they dove in to the data and tried to prove or disprove the hypothesis.

I'm still not sure that the local trend of population decline is a long-term indicator; but, there's a bunch of economies along the curve, and things seem fine, for now?

My worry is that this is a railroad fallacy: you can see the train coming, but it's not hitting you now, so everything must be fine in the long-term?

> This is the great part about science: whether or not you agree with the authors' conclusions, they just asked the question "is our preconceived 'obviously correct' conclusion actually correct". Then, they dove in to the data and tried to prove or disprove the hypothesis

Unfortunately it also shows the difficult part of modern scientific publishing: The authors try to downplay the existence of problems (labor shortages) by arguing that it's really a problem of immigration policies not allowing enough new labor in.

That's a tacit admission that labor shortages are a problem. Proposing a solution to the labor shortage doesn't mean that it's not a problem.

You have to read scientific papers carefully. It's increasingly common to find editorialization or wishful thinking mixed into the logic of papers. More so in some fields than others.

Actually, in social science you really can't test a hypothesis with data. What's true under one set of conditions won't be true under another and conditions change all the time. Famously, there's the Lucas critique - the idea that a relationship (or the lack thereof) between variables may break, if a policy that exploits the relationship is implemented.

Or take the matter of immigration and international conditions that many others noted in this thread. If every rich country depends on immigration and every poor country strives to become rich, at some point you are going to start running out of places to source immigrants from and there will be a relationship between birth rates and economic performance.