I’m midway through Alberto Cairo’s new book “The Truthful Art” and finding it very stimulating. It’s an interesting time to be a data scientist, journalist or consumer of data.
“The Truthful Art” encourages us to use data truthfully and fearlessly, and provides processes and principles to do so.
This week I noted a new study published by the Center for Immigration Studies (CIS). A recent Presidential Executive Order asserts that the US is in special danger from travelers from seven particular countries. The order is controversial and is currently being challenged in the courts.
The CIS study found that 72 individuals from the “seven terror-associated countries” were convicted in terror cases since 9/11/2001. The study offers this number as evidence of the exceptional danger posed by immigration from the seven countries.
It seems like there may be more of story here than “72 terrorists from seven countries”. The study provided a link to the raw data used. I undertook an evaluation of the data and conclusions using some of the techniques I had just been reading about.
The date used to select cases in the study was “Conviction Date”. A more meaningful date would be “Offense Date” Offense Date was not given, but a “Charge Date” was available. I saw this as a better proxy for when the offense occurred. As shown in the table below, the number of days between Charge and Conviction can be quite substantial. Using Conviction Date skews the offense into the wrong time period.
Days from Charge to Conviction
Now instead of looking at “72”, I “broadened” my view of the data as Cairo would suggest. What about the other countries? Are there slices of the data that provide insight?
When I plotted two country groups — banned and others — over time, an interesting story emerged. There are no defendants from the banned countries in the last three years of the study. This suggests that travelers from those countries may actually pose less risk than travelers from other countries.
After 9/11, US domestic counter-terrorism efforts were greatly expanded and overhauled. The decline shown in the chart suggests to me that the current screening procedures are effective and continually improving.
I’m going to continue my journey through “The Truthful Art“.