Blue Skies Above Us

Just here to have fun.


4-Minute Read

I’ve made a few twitter bots over the years. Some were good ideas, and some were bad ideas. I used them as opportunities to learn some python and ruby. I like bots! They take a day or two to setup, and then you just let them go.

Twitter is pretty strict about bots. When I create new ones, the account always gets banned 2 to 3 times BEFORE the bot has even tweeted once. Crazy, huh? Most of my bots are totally benign, but a few were annoying and rightfully banned (or disabled by me).


1-Minute Read

I started an Etsy shop called Coloring Maps. I’m selling digital downloads of street network maps that I’ve designed for coloring.

I also took photos to use as mockup templates.

I colored this one in digitally, just as an example.

This project was a good opportunity to learn: how to process and manage big OpenStreetMap datasets; how to create fun vector graphics for things like water, parks, beaches, etc; and how to create a workflow so I can churn these maps out pretty quickly. I’m trying to have it so most of the shop items are “packs” of multiple maps. I’m adding a few new packs a week.

The maps are made in QGIS (free software), using OSM data (free data). I tried other data methods (using local street network datasets), but that data was unreliable and it was a lot of work to process.

I created an instagram account for the project.

Next I may add some printable posters of cities.


1-Minute Read

I make a lot of maps at work. I made this one for fun, because the dataset – LA Assessor Parcel 2015 Tax Roll – has some cool fields in it. It’s a map of parcels containing single family homes in Los Angeles County, symbolized by the size of the main building on each one.

It was an easy map to make! And it contains over a million polygons!

Parcel map by house size

I posted this on reddit last week, and it got some attention. People like pretty-looking maps.


1-Minute Read

fart earth

I printed a bunch of stickers with the word FART emerging from the word EARTH. And since that might not seem deep, I then founded The Fart Earth Society, and wrote about why this graphic has a deeper meaning. If you want the sticker (it’s bumper sticker size), it’s $5! Visit the site for details, and some creative writing.


3-Minute Read

I recently completed my Master’s degree in Urban & Regional Planning from UCLA. Now I’m sharing my capstone project. This a research project I completed in my final year, with the Los Angeles County Bicycle Coalition (LACBC) as my client. The LACBC used some of the findings in their own report, the 2015 Bike Count Report. That link contains a nice synopsis of key findings, plus a link to download the whole report. The report is very digestible, with some great graphics. It shows the results of the 2015 bike count (I did the statistical analysis), as well as the results of my research on the safety impacts of newly-added bikeways in Los Angeles.

The two key findings are that bicycling has decreased since the last count (though it’s increased on bikeways), and that the new bikeways have made bicyclists safer.

I’ll admit that it was stressful to have to reveal to the LACBC that ridership was down. After all, one of their goals is to promote bicycling. But another one of their goals is improving safety (see Operation Firefly, for one). And so I believe the safety findings are important (and positive!).

My analysis measures changes in bicyclist-involved collisions as a function of ridership. This methodology, to be frank, makes it an exception among active transportation safety impact studies. Most seem to look at raw crash numbers, without accounting for ridership. A quick explanation for why this matters: if the number of crashes double after a bike lane is added, but ridership has quadrupled, then the rate of crashes has decreased (a simple analysis of raw crash numbers would state that crashes increased, even though safety per bicyclist had actually improved).

The bicyclist counts are conducted at discrete locations throughout Los Angeles. The counts take places every other year, and many sites are repeated each time. I identified all of the new bike lanes and sharrows in Los Angeles, and then narrowed them down to the ones with before/after counts. I found 17 sites that fit this criteria. I also included 18 control sites. The study finds that the rate of crashes per bicyclist declined by 43% after the installation of bikeways (there was no real difference between road diet, squeeze bike lanes, and sharrows). With respect to the control sites, ridership levels remained constant, while the number of crashes increased by 22%.

Read the entire report!

To Live and Ride in LA: Do Bike Lanes Make Angelenos Safer?

The report shows the detailed results for each study site. I’d love to hear feedback (not only comments about the results, but feedback on the methodology).


Recent Posts



Founded 2005. Over the years I've posted writing, comics, ringtones, and stuff about maps, bikes, programming, pinball. And I had a robust music blog mostly about '90s hardcore punk (category = music).