Tutorials

Posts with how-to examples.

Recent posts

Mapping Crime Data With CartoDB

Today I started playing with CartoDB, an online data mapping service that reminds me in some ways of both Google Fusion Tables and TileMill.

To start, I grabbed a simple test data set — five months of geocoded major crimes in D.C. from January to May this year — to check out some features. One I like is allowing users to query their data in the browser-based interface and filter for specific types of records.

Here, for example, I narrowed the map to show just thefts:

Assaults with deadly weapons:

Vehicle thefts:

Thefts from vehicles:

Robberies:

Homicides:

I made these maps in less than five minutes, so I’m sure there are much more useful stories to tell with the tool. There are also many, many features I didn’t explore, like the ability to style the map using Carto, the CSS-like language, rather than the UI.

Anyway, give it a shot, and let me know what you build.

Daily Data Links: Subway Map Mistakes, Data Tools, and Why Visualization Matters

Daily Data Links: Project Miso, Data Viz Future and Federal Budget Infographics

Daily Data Links: Mistakes to Avoid, Visualizing Twitter and Internet Freedom

Good morning. The Daily Viz, as you might be able to tell, has gotten a facelift. I’ve migrated the site from Tumblr to WordPress and installed NPR’s open-source Argo theme. The new platform offers more features, such as link roundups. These will become daily features in addition to posts of my own work:

Use Calendar Heat Maps to Visualize Your Tweets Over Time

Following Nathan Yau’s excellent tutorial for creating heat maps with time series data (he used vehicle accidents by day for a year), I visualized 3,559 of my tweets back to March 2009.

These maps, created with a modified R script from the tutorial, show how often I sent tweets (both personal and RT), with darker shades representing more activity. It’s fun to go back to the dark days and recall what sparked flurries of tweets: