This blog will be dedicated to examining and promoting civic data in Chicago, Cook County and Illinois.
WBEZ is partnering with the Smart Chicago Collaborative to promote civic data. This blog will be part of that collaboration.
We'll post original data sets @OpenSocrata
Chicago Transit Authority president Forrest Claypool had some biting words for the Chicago Sun-Times — on its own pages.
On Thursday, the CTA chief penned a letter to the editor, chastising the newspaper’s article on CTA crime that ran on Tuesday.
On Monday evening, the tabloid released an article online, utilizing data analysis about CTA crime. The front page of its Tuesday print edition ran with the headline: HIDE YOUR iPHONES.
Monday evening, the CTA countered with a release criticizing the analysis as flawed. The CTA’s main point of consternation was the Sun-Times claim of a 21 percent increase in crime.
The sub-headline of the front page story read: “CTA rail stations hit by 21% spike even with high-tech surveillance.”
In his letter, Claypool said the suggestions are “false and misleading.”
The CTA did not refute whether or not crimes actually happened, but rather what types of crime should be measured and how they were measured.
The premise of the story is that crime increased on or around CTA rail stations despite an increased use of security cameras from 2010 to 2012.
In order to determine that, reporters had to assess which crimes happened near the cameras. The methodology that defined which numbers were used is at the heart of why the CTA says one thing and Sun-Times said another.
Given WBEZ’s commitment to data reporting that helps Chicagoans make sense of their city, we’re hoping to demystify the numbers… with a hilariously long-winded post on data.
The CTA crime story has made its way from online and print to subsequent TV reports.
And before sheer repetition turns this story’s claim into a commonly accepted idea among Chicagoans, we decided to look a little closer at the numbers.
If you don’t want to get into the weeds of data, numbers and variables, then the gist is this:
The tragic murder of a 15-year-old girl has led to an examination of the relatively quiet Chicago neighborhood: Kenwood.
Hadiyah Pendleton, a King College Prep freshman was fatally shot when her and friends took cover from the rain under a canopy at Vivian Gordon Harsh Park on the 4500 block of South Oakenwald Avenue around 2:30 p.m. Tuesday.
While the community area has not racked up homicides in the numbers we see in the Austin or Englewood neighborhoods, they have gotten murders over the past 10 years.
And while overall crime, like overall crime in Chicago seems to be on the decline, there are some unsettling trends in a neighborhood roughly only a a square-mile in size.
Utilizing police data from the city’s data portal site, we were break down to map annual crime in the area as well as map it out.
Here’s a map of all reported crimes in Kenwood for 2012.
When breaking apart the year to year, there are a couple of things worth noting.
The neighborhood has seen modest decreases in theft, car thefts and robberies. But what few shootings and homicides the neighborhood saw over the past 10 years has stayed relatively consistant in the single digit range.
Calculating things can be hard for journalists.
Actually, most journalists go into journalism because we’re bad at math — or so the joke goes.
In my story about pot arrests vs. tickets, I first looked at the annual numbers. The ever-popular Crimes 2001 to present data set. I was trying to discern a trend, seeing if the ticketing ordinance had an effect on arrests.
At first glance, it looked like a yes-or-no situation. The reason: pot arrests seemed on a decline from a peak in 2007, briefly going up in 2010, then falling again in 2011.
Here’s a chart:
Now, from the chart, the decline in 2012 seemed like a natural part of the overall decline. If that were the case, then the tickets had very little impact on arrests.
It wasn’t until I broke out the monthly year over year totals that the staggering drops stood out:
The drops are much more acute in August. Now, taking the monthly totals from the tickets issued that month (110), a person can reasonably assume that a 831 drop in year over year arrests would not be natural, especially when the previous months were showing steady declines.