The Mirrlees review also has some interesting thoughts on progressivity itself.
From the economist.com
Mr Obama seems to care greatly about progressivity and not at all about efficiency.
From the economist.com
Multiple brackets have literally nothing to do with the progressivity of tax burden.
From the economist.com
Progressivity of income tax rates only shrinks the College E differential.
From the forbes.com
Progressivity in the income tax make such adjustments politically contentious though.
From the economist.com
Indeed, the U.S. has been diminishing progressivity of its tax structure for decades.
From the sciencedaily.com
That is a completely separate issue to the progressivity of the tax system.
From the economist.com
Cain's approach treats simplicity and progressivity as if they were mutually exclusive.
From the latimes.com
Once this is established, creating progressivity with a shared burden makes more sense.
From the economist.com
More examples
Progressiveness: advancement toward better conditions or policies or methods
A measure of how tax burdens increase with income. A progressive tax claims a proportionately larger share of income from higher-income than from lower-income taxpayers. Conversely, a regressive tax takes a larger share of income from lower-income households than from higher-income ones. ...