Try the math for yourself (requires Maple)

Illustration of the Romney Tax Plan 

(In which we learn that the math adds up, but the real world assumptions may not) 

> restart; 1; with(Statistics); -1; with(plots); -1; e := exp(1); -1
 

We will approximate household income as being gamma distributed.  

We are able to match our CDFs to available data points quite closely. 

> gammacdf := proc (x, k, theta) options operator, arrow; `/`(`*`(`+`(GAMMA(k), `-`(GAMMA(k, `/`(`*`(x), `*`(theta)))))), `*`(GAMMA(k))) end proc; -1; gammapdf := proc (x, k, theta) options operator, ar...
 

Approximate all households of a particular income pay the same (2012) taxrate (ignore marital status, etc). 

> incomebrackets := Vector([0, 10500, 18500, 22500, 30000, 35000, 55000, 62500, 77500, 92000, 167000, 250000, 350000], datatype = float); -1
incomebrackets := Vector([0, 10500, 18500, 22500, 30000, 35000, 55000, 62500, 77500, 92000, 167000, 250000, 350000], datatype = float); -1
 

> tb := [0, 17400, 70700, 142700, 217450, 388350, 1000000]; -1
 

Feed in 2006 data for US, and a simulated Romney-world where income tax has been cut across the board by 20% 

> incomeupperpercentiles := Vector([0, .1, .2, .25, .33, .4, .6, .67, .75, .8, .95, .985, .99], datatype = float); -1
incomeupperpercentiles := Vector([0, .1, .2, .25, .33, .4, .6, .67, .75, .8, .95, .985, .99], datatype = float); -1
 

> incometaxf := proc (i) options operator, arrow; piecewise(`<`(i, 17400), .1, `and`(`<=`(17400, i), `<`(i, 70700)), .15, `and`(`<=`(70700, i), `<`(i, 142700)), .25, `and`(`<=`(142700, i), `<`(i, 217450...
incometaxf := proc (i) options operator, arrow; piecewise(`<`(i, 17400), .1, `and`(`<=`(17400, i), `<`(i, 70700)), .15, `and`(`<=`(70700, i), `<`(i, 142700)), .25, `and`(`<=`(142700, i), `<`(i, 217450...
 

> romntaxf := proc (i) options operator, arrow; `+`(`*`(`/`(4, 5), `*`(incometaxf(i)))) end proc; -1
 

> dataplot := plot(incomebrackets, `+`(`*`(100, `*`(incomeupperpercentiles))), color = green); -1
 

> guess := plot(`+`(`*`(100, `*`(gammacdf(i, 2, 22000)))), i = 0 .. 350000, color = black); -1
 

> Fit(gammacdf(i, k, theta), incomebrackets, incomeupperpercentiles, i, output = parametervalues, initialvalues = [k = 2, theta = 22000])
Fit(gammacdf(i, k, theta), incomebrackets, incomeupperpercentiles, i, output = parametervalues, initialvalues = [k = 2, theta = 22000])
 

[k = HFloat(1.4412610258235732), theta = HFloat(39576.22398588795)] (1)
 

Here are curves to match some real world data (2006) 

> curpdf := proc (i) options operator, arrow; gammapdf(i, 1.44126102582357, 39576.2239858879) end proc; -1; curcdf := proc (i) options operator, arrow; gammacdf(i, 1.44126102582357, 39576.2239858879) en...
curpdf := proc (i) options operator, arrow; gammapdf(i, 1.44126102582357, 39576.2239858879) end proc; -1; curcdf := proc (i) options operator, arrow; gammacdf(i, 1.44126102582357, 39576.2239858879) en...
 

Here are some example curves that would increase revenue while cutting taxes 20% across the board 

This is the fishy part of Romney's plan. He's offered no numbers to support the claim that his plan 

for the economy would produce anything like this. 

> rompdf := proc (i) options operator, arrow; gammapdf(i, 1.7, 50000) end proc; -1; romcdf := proc (i) options operator, arrow; gammacdf(i, 1.7, 50000) end proc; -1
 

> rom2pdf := proc (i) options operator, arrow; gammapdf(i, 3, 25000) end proc; -1; rom2cdf := proc (i) options operator, arrow; gammacdf(i, 3, 25000) end proc; -1
 

> fitplot := plot(`+`(`*`(100, `*`(curcdf(i)))), i = 0 .. 350000, color = blue); -1
 

> romplot := plot(`+`(`*`(100, `*`(romcdf(i)))), i = 0 .. 350000, color = red); -1; rom2plot := plot(`+`(`*`(100, `*`(rom2cdf(i)))), i = 0 .. 350000, color = red); -1
romplot := plot(`+`(`*`(100, `*`(romcdf(i)))), i = 0 .. 350000, color = red); -1; rom2plot := plot(`+`(`*`(100, `*`(rom2cdf(i)))), i = 0 .. 350000, color = red); -1
 

Plotting %US Households < particular household income 

Black line is the "best guess" we fed into the curve fitter.  

Blue is the output distribution that is the result of a least squares  

regression to the gamma CDF. Green is real world data.  

Red lines are possible "Romney-world CDFs" 

> display([guess, fitplot, romplot, rom2plot, dataplot])
 

Plot_2d
 

Distribution function showing modal income.  

Normalized so that the total area under the curve  

represents the number of households (i.e., area scaled by 1/110000000) 

> curpdfplot := plot(curpdf(i), i = 0 .. 100000, color = blue); -1
 

> rompdfplot := plot(rompdf(i), i = 0 .. 100000, color = red); -1
 

> rom2pdfplot := plot(rom2pdf(i), i = 0 .. 100000, color = red); -1
 

> display([curpdfplot, rompdfplot, rom2pdfplot])
 

Plot_2d
 

And some income-tax revenue calculations based on our approximated real world 

compared with 2 possible Romney worlds. 

> currevenue := `+`(`*`(110000000, `*`(int(`*`(incometaxf(i), `*`(i, `*`(curpdf(i)))), i = 1 .. 1000000, numeric = true))))
 

0.1357320970e13 (2)
 

> romrevenue := `+`(`*`(110000000, `*`(int(`*`(romntaxf(i), `*`(i, `*`(rompdf(i)))), i = 1 .. 1000000, numeric = true))))
 

0.1838607340e13 (3)
 

> rom2revenue := `+`(`*`(110000000, `*`(int(`*`(romntaxf(i), `*`(i, `*`(rom2pdf(i)))), i = 1 .. 1000000, numeric = true))))
 

0.1484865290e13 (4)
 

Conclusions: It IS possible to cut taxes across the board while increasing revenue.  

The real question is whether or not the economic assumptions required to do so are valid. 

I do not have any data on this point. So the question is,  do you believe Romney's election 

can effect the economy this drastically? 

 

For a much simpler and more assured path to a balanced budget,  

check out Libertarian Presidential Candidate Gary Johnson. 

>