Our family likes to keep track of the license plates we see while we're on road trips (and since we are attempting to visit every county in the country, we go on a lot of road trips). One thing I've noticed is that we always end up looking for the same difficult-to-see license plates at the end of each trip. What's interesting is that it's not necessarily connected to state population.
Of course it's easy to see a state's license plate in that state, and should be easy to see it in a neighboring state. But what explains the differing difficulty in seeing an Arkansas license plate and seeing a Mississippi license plate? Their populations are nearly identical and they share a border. Once you are outside their immediate area, you should expect to see their license plates with equal frequency. But I can tell you that Arkansas is substantially harder to see than Mississippi is.
Why are people from Arkansas so much less likely to drive around the country? Maybe they are much poorer than Mississippians. Except they're not. While both states are in the bottom three when it comes to median household income, Arkansas is ahead of Mississippi. My wife thinks it might be a reflection of less urbanization, that city folk travel more than country folk do, so Arkansas must be more rural than Mississippi is. But I don't think that's true. The largest urban area in both states is Memphis, and since that covers parts of three states, let's just ignore it for a moment. The second-largest urban area in each state is the state capital, and Metro Little Rock is larger than Metro Jackson. Arkansas's third-largest urban area, Bentonville, is larger than Mississippi's third-largest urban area, Gulfport. Unless Metro Memphis is substantially skewed towards Mississippi and away from Arkansas, I'd say Arkansas is the more urban of the two states. (Mississippi is a denser state, but that's because it's a smaller state, which is not necessarily an indication of urbanization.)
So what about Metro Memphis? Is that where all the globe-trotting Mississippians live? Well, I don't think so. While it's true that the Mississippi portion of Metro Memphis is larger than the Arkansas portion, we can see here that the total population of Arkansas's metro areas is larger, and this is still true if we limit ourselves to only looking at Arkansas's largest metro areas. ("Arkansas's largest metro areas" is not a phrase that has ever been written before.)
If it's not a matter of affluence, and it's not a matter of urbanization, is it a question of interconnectivity? I don't think so, because I think Arkansas's connection to the Interstate Highway System is better than Mississippi's. I-20 and I-59 aren't providing the access to the rest of America that I-30 and I-40 provide.
Then it must be a result of state taxation regimes, right? Like how lots of truck fleets are registered in Indiana, and all U-Hauls are registered in Arizona. Mississippi must have a much more favorable registration process for motor vehicles. Except it doesn't seem like that's true, either. Arkansas has over 100,000 more registered vehicles. Given that the states are of nearly-identical populations, and that Arkansans have only slightly-higher incomes than Mississippians, that's quite a difference.
The only explanation I have left is this: Arkansans are more provincial than Mississippians.