Correlation vs. Causation

In case you needed any more evidence of the link between fossil fuel imports (at least, from Norway) and harm to people’s health, I present you:

Solving an arithmagon

One of my nephews was working on an “arithmagon” puzzle. Here’s an example puzzle:
The idea is to solve for a, b, and c such that:

a + b = 26
a + c = 33
b + c = 35

and, I guess, the idea at his young age is to try different numbers ad-hoc until you find the ones that work.

Well, of course, that’s not how I think these should be done. ūüôā

In general:

we have:

a + b = X
a + c = Y
b + c = Z

Three unknowns (a, b, c) and three linear equations; we can solve for the general case:

b = X - a
c = Y - a


b + c = Z
using b = X - a and c = Y - a:
X - a + Y - a = Z
X + Y - 2a = Z
X + Y - Z = 2a

a = (1/2) * (X + Y - Z)

So we get a = 12 for the original example shown at the start, and from that (using c = Y – a and b = X – a) c = 21 and b = 14.

Easy! Sorry for ruining all the puzzles for my nephew (once he can understand algebra).



Inspired by a friend’s recent Facebook posting, I tallied up the Politifact statistics for 4 Democrats and 4 Republicans: Obama, Biden, Pelosi, Reid, Boehner, Romney, Perry, and Gingrich.

Politifact has six ratings: True, Mostly True, Half True, Mostly False, False, and the crowd-pleasing Pants On Fire.

Here is the raw data (counts for each ruling):

NAME      True      Mostly True      Half True       Mostly False      False      Pants on Fire

Obama      80              74                   79                  42                 51             4

Biden       11               11                   11                   8                   6              3

Pelosi        1                 2                     9                   2                   3              2

Reid          2                 2                     3                   3                   3              1

Boehner   15                3                     4                   9                  16             1

Romney    20             15                   19                  13                 13             8

Perry        15             10                   30                   22                 23            11

Gingrich     3              3                     9                    6                    9              6

There are, of course, problems with this data. I don’t know how Politifact decides which statements to check. The selection process is likely biased in several ways. For example, perhaps controversial or likely-false statements are more likely to become Politifact fodder in the first place. Thus I would be hesitant to conclude that any of the above people are lying X% of the time in general, just because X% of their rulings are False or PantsOnFire. There are a variety of other problems lurking here, especially when the data is thin like for Pelosi and Reid.

Nevertheless, let’s do some math for the fun of it.

In aggregate, 21% of the statements ruled on are TRUE. Boehner is highest at 31% and Pelosi is lowest at 5% (but her data is so thin; one more “true” statement and she would have been 10%). The four Democrats scored 23% in aggregate and the GOP scored 19%.

Expanding to include “mostly true” (and the fully-true), the aggregate is 38%, with Obama best at 47%, and Pelosi and Gingrich bringing up the rear at around 16%. The four Democrats were 44% mostly-true or true, and the GOP was 30%.

False or Pants on Fire is 23% in aggregate. Gingrich is the run away winner here at 42% with Obama the best, of a sorry lot, at 17%. GOP 31%, Democrats 18%.

I also looked at the rulings for the DNC and the RNC. Their numbers:


True      Mostly True      Half True       Mostly False      False      Pants on Fire

DNC    6             5                   8                       6                     2                 0

RNC     2             4                   8                      5                     5                  2

This nets out to DNC being Mostly True or True 41% of the time, and the RNC only 23%.

The data is at the very least suggestive that the Republicans, in aggregate, are less truthful than the Democrats though we’d really have to do a more scientific survey (better selection methodology) to draw any real conclusion. Neither party appears to deserve a gold star for veracity.

Welcome to

Well, I finally decided to upgrade my site from vintage 1997 “I edited this by hand with emacs, just barely one step up from hammer and chisel” … trying out WordPress. Nothing terribly fancy, just another blog.