Announcing "Truth Index+"

While PolitiFact's Truth Index scoring methodology appropriately penalizes the lower scores, particularly Pants on Fire, it also distorts the overall score in a way that prevents valid comparisons from being made.   It basically takes comparisons out of proportion.   It is also more difficult to graphically present with its negatives.

 

Back in 2010, I began with a grading system called the Politi-Score, where a True was an A+ at 100, a Mostly True was a B at 90, down to a 50 for a flunking Pants on Fire.  That wasn't bad but it also made comparisons too "tight".  I then tried starting at 100 points working down to negative 25 for Pants on Fire, because others in a PolitiFact discussion group I presented my work in seemed to feel that the penalty was necessary as well.  About that time PolitiFact created its own measure called the Truth Index, which starts at 100 for True, makes Half True the zero and then goes down to negative 150 for Pants on Fire.  While I've stuck with that for a while now, I've realized in order to attempt things like standard deviations or z-scores, negatives might be difficult to work with.

 

This time I decided that True will be scored at 100 working down by equal 20 point increments to zero for Pants on Fire.  This will also make it easier for doing graphs by doing away with the negatives.  It also makes percentage comparisons easier to understand because the scores are perfectly proportional.  It is almost the equivalent of a percentage measure in and of itself.

 

So now a timeline can be developed from the beginning (2007) until the end of September of 2012.   I've also included the cumulative timeline for the Congressional Quarterly--the group that worked with PolitiFact when it first began in 2007, ending at the end of 2008.  This chart shows the Democrats Truth Index+ versus the Republicans, and the results aren't surprising considering everything else published on this blog.  The period measure is quarterly for the cumulative Truth Index until the end of 2008, to show the Congressional Quarterly Index, after which it is annual, so the chart would be less cluttered.

 

Click to enlarge: CQ rulings stop at end of 2008 when CQ-PolitiFact partnership ended

So today it can be said that based on 2,463 PolitiFact National rulings, it rates a Democrat about 29% more truthful on the Truth-o-Meter than a Republican.  And the largest drop in the Republicans Truth Index occurred from the end of 2008 until the end of 2009 (about 7%).  Whether it's because the Congressional Quarterly was no longer assisting is disputable--my feeling is it had something to do with the new Democrat president's term and the advent of healthcare reform in congress.

 

Next up will be a look at the "Pants on Fire" factor for the same data.