There is good reason to believe, I think, that the demographics across the two countries are pretty similar (though certainly not identical). If the type of economic activity along the border is roughly similar across the two countries, then one might reasonably expect similar labor market behavior in Canada and the border states. But this is not what we see at all.
The chart above is of the Employment-Population ratio in the two countries (with the US border states shown separately).
Read the whole article here.