I'm an engineer, trained to use mathematics as a tool, adept at reading technical documents where graphical elements are used to enhance comprehension. But obviously IRS instructions are cast from a different mold.
A serious peeve, from an engineering standpoint, is the wordiness of IRS documents, especially when describing what are in essence simplistic mathematical expressions, coupled with an almost total absence of explanation for the rationale behind some of the tax rules. And of course, I'm appalled to see page after page of tables that seem to be nothing more than a tabulation of simple linear equations.
This blog wants to apply mathematical concepts to give visual explanations of tax rules and to show that their form does (or sometimes doesn't) make sense. A first sequence will tackle the concept of marginal rates, with the explicit intention of explaining how the curve below, extracted from "Effective Marginal Tax Rates on Labor Income", a Congressional Budget Office document, can be recreated.
The CBO is a government office. As such the documents it produces are not copyrighted. This is confirmed by an explicit copyright policy, that however requires correct attribution. So please mention the CBO origin if you want to use the above chart elsewhere.