One of the ways we're learning about maps is by watching how cartographers react to maps we tweet (Us: "Check out this neat map!" Them: "Um, no. Here's why..."). Now we can spot some of the most common problems, like maps that aren't normalized or have problematic color schemes.

We'd like to bring some of that discussion to Map Lab so we can learn more from the pros, and you can too. The idea isn't to find bad maps and rip them apart, but to talk about how some maps could be better.

This first in our Carto-Critique series is the map above of subscribers to New York City's bike-sharing system called Citi Bike. The map appeared on DNAinfo New York today and was brought to our attention by Jessie Braden and Steven Romalewski:

As mapping professionals, is it our duty to offer corrections for bad maps/analysis we see on the web? Ex: October 22, 2013

The story's author (and mapmaker?) James Fanelli gamely joined in and welcomed the discussion.

@fanellijames Hi James! For this analysis it's critical to account for population density. I might even factor in bike dock density. — Jessie Braden (@JessieBraden) October 22, 2013

Braden offered the normalization section in this resource: www.gsd.harvard.edu/gis/manual/normalize/ and suggested changing the color ramp and making "0" a separate class.

@fanellijames Yep, the tough part of web mapping! Sometimes hard wh multiple layers. But, it'd be great to see alignment of docks/members. — Jessie Braden (@JessieBraden) October 22, 2013

The only thing I'd add is that I wish the pop-out map was bigger. At 500 pixels across, you have to zoom out pretty far to see the whole data set. But maybe this is a technical constraint of the website.

We'd love to hear your thoughts and suggestions in the comments below!