Right now the best data I know of is the results of raising the pay of CEOs. That data is not promising for politicians.
The problem with low pay is, if you get out the stick, you're only left with people with nothing left to lose. The bottom of the barrel.
With higher pay, people have something to lose. But unless you have policies and incentives to make them fear that loss, they'll still just coast along and assume they deserve the money just for showing up. Some are, of course, intrinsically motivated to do a good job but that motivation can dry up seeing how coworkers act daily.
When I say fear, I don't mean the kind that makes you dread coming to work. Just the usual fear of failure that makes you want to do something well to avoid the downside. How to set that up? I'm not a teacher, but I bet teachers out there know who the bad ones are so there's probably a way to do it. The same for other jobs.
My concern though is teachers are so distracted making fiscal ends meet that they can't bring their all to the classroom...
> My concern though is teachers are so distracted making fiscal ends meet that they can't bring their all to the classroom...
Yes that's another part I didn't mention, and a living wage will address that. But you also have cases where they spend their own money on classroom supplies due to poor funding so you'd want to address that too. Once everyone is comfortable though, you need to make sure it doesn't turn into indolence which is what I was getting at.
However, contrary to popular belief "more is always better" throwing money at problems isn't always a solution. I was in academia, and often vast amounts of money were thrown about without planning or oversight, and it never worked out.
I like the sentiment, and we shouldn't let fear of unintended consequences prevent all human progress, but there are significant risks with regard to unintended consequences and concentrating government powers on wages and social programs beginning to approach failed utopian experiments of the past.
As other commenters have skillfully pointed out, this would likely have deleterious effects unless, as you say, it was implemented in a fully-downstream fashion to include the whole pool of workers including contractors and the like.
And of course, when regulations get too stiff in one city or state or nation, companies move. That is also a big obstacle in this idea. But there is at least one company that has the CEO salary capped at a certain number of multiples of the lowest-paid employee, and their culture seems to be great.
For instance, I'd expect 50% increases to have little to no impact.