Monday, July 29, 2013

OpenLayers 3.0

OpenLayers is a great resource for those wanting to put a map on the web.  Simply put, OpenLayers "is a pure JavaScript library for displaying map data in most modern web browsers, with no server-side dependencies." Many posts ago, I used OpenLayers to post a web map.

New features will include a more accessible API and a host of other features.  An alpha version is currently available for download:

If you have not seen OpenLayers libraries before be sure to check out:

Monday, July 8, 2013

AIDSVu Map Provides Better National View of the Epidemic

AIDSVu Map provides the "most detailed publicly available view of HIV prevalence in the United States"  It is a "compilation of interactive online maps that display HIV prevalence data at the national, state and local levels and by different demographics, including age, race and sex."

Estimates of the prevalence of persons living with HIV go from the state and county level down to ZIP codes and census tracts in the United States.  AIDSVu was produced by the Emory School of Public Health.  In addition, it provides aggregate data for download and use.  The website uses OpenStreetMap. Click either of the screenshots below to enlarge them.

An Overview of Several Cities

The Epidemic in Houston
In addition, the group does a good job explaining the methods for protecting patient privacy--avoiding cases where a person's identity may be surmised from sparse population, data, or a combination of circumstances.

However, it would be nice to see some spatial analysis doneor overlays with socioeconomic data to help the viewer understand patterns.  Overall, the map performs very well on the web.  Zooming-in is relatively straightforward and the map renders well--but is quite flicker-y.  Maybe a projection issue? It is good to see some agencies using census tracts over ZIP codes because of the ease to link them to Census and American Community Survey (ACS) Data.