That’s no news, but this seems to be a paper that confirms it. Abstract says that the proportion of “potential” income realized as actual taxable income by high income households declined when tax rates increased, while that of low income households grew when their tax rates dropped. That is, folks work more or less hard, depending on what proportion of their income they’ll get to keep.
This seems to be what the paper says, but it’s behind an ssrn screen so I can’t actually get a copy. Abstract from taxprofblog.