That doesn't seem very relevant. Obviously there are places where you can realistically only build one or the other, but there's lots of places where you can build either, and if your goal is to increase housing density, those are the places you're interested in (regardless of what your method is).
edit: and it's also obvious that density can be affected by zoning laws, but I was assuming those are held constant (because a, they kind of are constant in that they don't change much, and b, the present phenomenon of rents rising sharply since 2005 is, I think, not generally believed to be caused primarily by a change in zoning regulations)
In most areas that have single-family houses, it is illegal to build 16-unit apartment buildings. In the places that most need more housing, this is the most true.
I guess I should've used a more realistic example (one home vs a duplex, or a 16-plex vs four single-family homes) but I really thought the point would be obvious. I guess not, so I'll try again.
You recognize that there are occasions when a developer has the option to build more density or less density on a specific piece of land, yes? I was using an exaggerated example (1 vs 16) to illustrate the more general concept of less-vs-more. I am arguing that, other things being equal, higher wealth inequality will lead to developers choosing to build less density, because an increase in wealth inequality implies that the rich have more to spend than the poor (relative to whatever previous period you're comparing to that had less wealth inequality).
