Category: Cities

Finding a new way to measure cities’ bike friendliness in the United States

November 3, 2012 / / 8 Comments

A really smart person could come up with a way to measure day-to-day bike friendliness based on how well cities adhere to standards that keep roads clear of obstructions that further frustrate the commute, like construction projects that squeeze bikes and cars together. 

I work at home. There are some days when I only leave my house to get milk from the Mexican grocery store at the end of my block (which makes awesome burritos). That means I ride my bike half as much as people who commute to work. on their bikes. Today I had a bunch of errands to run: drop off stuff, buy stuff, take pictures of stuff for my blog, Grid Chicago.

It was a very frustrating experience. I don’t need to go into details about how I was harassed by people who the state so graciously awarded a license to drive. But it happened. And it happens a hundred times a day to people cycle commuting in Chicago. I got to thinking about “bike friendly” cities. Is there a way to incorporate driver attitudes in there? I tweeted:

[tweet_embed id=264575958374305792]

Later I had the idea to use some very simple but objective measurements to create a new bike friendliness metric. It would help ensure that “Silver” (a ranking the League of American Bicyclists [LAB] uses) in one city means the same as “Silver”. It can expand from here but basically it works like this:

  • The share of people going to work who go by bike is a proxy for how “friendly” a city is to biking.
  • If a city has a lot of people biking to work, it must be friendly.
  • If a city has a few people biking to work, it must be non-friendly.
  • Cities are compared to each other to determine friendly and non-friendly.
  • The metric uses standard deviation to score cities.

Stop me if this has already been done.

I created a spreadsheet that lists the top 10 populous cities in the United States. I then added 10 more cities: Austin, Boston, Davis, Madison, Minneapolis, Portland, San Francisco, Seattle, and Washington, D.C. In the next column I listed their bike commute share from the American Community Survey 2006-2010 5-year estimates. I calculated the standard deviation and mean of these shares and then in another column used Apple Numbers’s STANDARDIZE function:

The STANDARDIZE function returns a normalized value from a distribution characterized by a given mean and standard deviation.

I think that’s what I want. And the output is close to what I expected. I then found the LAB ranking for each city and found the variance of each ranking to see how far apart each city within one ranking was from another city in the same ranking. The results were interesting: the higher the ranking, the more variance there was.

Hurricane Sandy prompted a lot of New Yorkers to bike. It made headlines, even. Photo by Doug Gordon. 

I wanted to add another metric of bike friendliness, and that’s density. To me, a higher density of people would mean a higher density of places to go (shop, eat, learn, enjoy) and friends and family would be closer, too. Or the possibility of meeting new people nearby would be higher. Yeah, I’m making a lot of assumptions here. So I applied the STANDARDIZE function there as well. I added this number to the previous STANDARDIZE result and that became the city’s score.

So, in this new, weird ranking system, the most bicycle friendly cities are…drum roll please…

  1. Davis, California (Platinum)
  2. New York City (Silver) *
  3. San Francisco (Gold) *
  4. Boulder (Platinum)
  5. Boston (Silver)
  6. Philadelphia (Silver)
  7. Tie: Chicago*, Washington, D.C. (Silver)
  8. Tie: Portland* (Platinum), Minneapolis* (Gold)

Remember, I said above that any author of a list should spend at least a day cycling in each city. I’ve starred the cities where I’ve done that – I’ve cycled in 5 cities for at least a day.

I only calculated 20 cities. Ideally I’d calculate it for the top 50 most populous cities AND for every city that’s been ranked by LAB.

LAB cities list (PDF). My spreadsheet (XLS).

Comparing how bikes and buses interact

October 26, 2012 / / 8 Comments

A photo from Los Angeles, filling in for a lot of North American cities (less Montréal):

Photo by Metro Los Angeles. 

A photo from Amsterdam, filling in for a lot of European cities:

Photo by Boudewijn Deurvorst. 

Where would you rather bike?

See more photos of bikes and transit in the eponymous Flickr group.

Links between pedestrian safety and crime

October 25, 2012 / / 4 Comments

Chicago Pedestrian Plan

Safety item 20: Analyze the relationship between pedestrian safety and crime (download the plan)

The 2011 Chicago Pedestrian Crash Analysis identified a strong correlation between community areas with high numbers of pedestrian crashes and community areas with high crime rates. Correlation does not indicate causation and further study is necessary to understand this relationship and the potential broader benefits of pedestrian safety improvements. [From page 62 in the 2012 Chicago Pedestrian Plan.]

ACTIONS

Short Term

  • Identify and obtain funding for this study.
  • Identify a location for safety improvements and obtain data for the “before” conditions.

Mid Term

  • Design and implement pedestrian safety improvements.
  • Develop a pedestrian safety enforcement plan for the area for the duration of the project.
  • Analyze the effects on pedestrian safety and crime.

MILESTONES

  1. Initiate this study by 2013 and complete by 2015.

ADDITIONAL RESOURCES

National Highway Traffic Safety Administration. Data-Driven Approaches to Crime and Traffic Safety (DDACTS). 2011. [I don’t fully see the connection, but this reference was linked to a page on NYC Department of Transportation’s website.]

Pedestrian Crash Analysis

The summary report didn’t contain the word “crime”. The technical report contained 2 mentions, with an additional chart. They are quoted in the ordered list below. Download the summary report.

  1. In an examination of various factors including crime, income, race, language spoken, and Walk Score®, the strongest correlation found was between pedestrian crashes and crime
  2. Finally, crime statistics were compared to pedestrian crashes to determine if a correlation could be identified, using data from the Chicago Police Department (CPD) annual reports for 2005 through 2009. The annual reports include incidences of crime by Chicago Community Area (CCA). The statistics for the years 2005 through 2009 were averaged and compared to the aver- age number of fatal and serious injury pedestrian crashes over the same time period in each CCA. Of these factors, crime was the only variable that correlated to pedestrian crashes. Figure 1 shows the correlation between crime and pedestrian crashes was very high. However, there may be many variables responsible for this correlation.
  3. Figure 1: Crime vs. Fatal and Serious Injury Pedestrian Crashes by Chicago Community Area

Figure 1.

I have a few criticisms of this analysis: it lacks raw data; the data tables included in the technical report are of limited length, listing only the “top” items of any metric; the summary report lists many silly factoids; the maps are low resolution and of a limited scale – their design could be modified to improve their usefulness in communicating the crash frequencies of the marked locations. The analysis is reliable.

The technical report includes the state’s guide on how police officers are trained to fill out a crash report form. It also includes relevant crash reporting laws in Illinois. Download the technical report.

Special post for S.M.

Some reasons why the CTA doesn’t make its own mobile apps

October 10, 2012 / / 0 Comments

Where’s the train?

“Twitter updated their app and now it sucks”. (Here’s some evidence.)

Have you heard that before? Thankfully there are tens – perhaps hundreds – more options to post to and read Twitter on your appy device.

The Chicago Transit Authority provides 1.7 million rides per day. A lot of passengers like to know where the trains and buses are. And it’s possible to know with many tools like Bus Tracker and Train Tracker, both of which are available through APIs, SMS, and websites.

Some people (eh, I can’t exactly point out who right now) have noted (complained?) that the CTA doesn’t make its own app for smartphones and tablets. I’m glad they don’t!

Here are more reasons why the CTA doesn’t make its own mobile apps:

  1. It would be racist of the CTA. (Pretty much everything the CTA does is racist according to someone but making an app would only be useful to those with compatible devices, so it’s probably more accurate to say income discrimination.)
  2. Bus service is getting cut but they’re spending money on making apps.
  3. There are 4 platforms to write apps for (at least 4 – not sure if any CTA passengers would demand Symbian or webOS).

The best reason?

Developers can do it better. So the CTA gives them the tools.

Is there a member of the ITE who will stand up against bad road designs?

October 1, 2012 / / 25 Comments

Sharing the road is one place to start. Why should one on a two-wheeled, muscle-powered device pedal along side a garbage truck with blind spots? Wait, why does an automobile even have blind spots? This enormous right-turn lane is one example of “dangerous by design”. 

Update October 5, 2012: For a great example on why I cannot – and why you should not – support bad road designs is this story of a fatal bike crash on a major biking “commuterway” in Chicago. We must stop building narrow bike lanes to the left of parked cars and we can be done with this type of crash for good.

The infrastructure as we have it in Chicago and many other American cities cannot support any increases in bicycling. The operation and design of our infrastructure creates a finite limit for the number of people who will bicycle on it. I’m not talking about how many people can use it, but how many people want to use it.

We’ve seen infinitesimal growth in the bicycle’s mode share for commuting to work, so small that the growth might not actually be growth at all because all the reported increases are within the range of error (the Census Bureau being the collector and distributor of the data). Our infrastructure is not safe, and that is what inhibits an increase in bicycling riders and trips that the City of Chicago, its mayor, its council, its officially adopted plans, and its people, desire. Until our roads are made safe, the cycle growth will remain minuscule or non-existent. The only other significant factor in promoting cycling is high gasoline prices, but even as they remain high, the cycle growth (or spike, seen in 2008) hasn’t returned.

It’s a small group of people who are designing and maintaining our roads. And they are the first group of people we listen to when we say we want safe roads. Instead of the people who’ve actually built safe roads.

The ITE is the Institute of Transportation Engineers, and, like many organizations, has a code of ethics. In their Canons of Ethics document (.pdf), there are at least two sections that require members to stand against bad road designs.

Section 1: The member will have due regard for the safety, health and welfare of the public in the performance of professional duties.

Section 11: The member will guard against conditions that are dangerous or threatening to life, limb, or property on work for which the member is responsible, or, if not responsible, will promptly call such conditions to the attention of those who are responsible.

A study in Portland, Oregon, found that 60% of residents wanted to bike, but had concerns about safety.

These residents are curious about bicycling. They are hearing messages from a wide variety of sources about how easy it is to ride a bicycle in Portland, about how bicycling is booming in the city, about “bicycle culture” in Portland, about Portland being a “bicycle-friendly” city, and about the need for people to lead more active lives. They like riding a bicycle, remembering back to their youths, or to the ride they took last summer on the Springwater, or in the BridgePedal, or at Sun River, and they would like to ride more. But, they are afraid to ride. They don’t like the cars speeding down their streets. They get nervous thinking about what would happen to them on a bicycle when a driver runs a red light, or guns their cars around them, or passes too closely and too fast.

American roads are dangerous by design. It’s time to fire the people who design them that way.

Year after year, roads in Chicago are ripped up, repaved, and restriped in exactly the same way that existed before. Miles of missed opportunities for safer roads. This essay says nothing of the lack of police enforcement of traffic rules, for which there is little empirical evidence. The essay may be updated from time to time, but I won’t be noting each change.

An example of a better design: the buses and bikes don’t mix, and automobiles turning left cannot be passed by through-automobiles. Bicyclists are safer.