One side of the fence really is greener, and now on the Internet you can see whether it's yours.

For those needing to know if they and their neighbors make more money than the next neighborhood over, or where the cheaper houses really are when transportation's factored in, a new Web site comes to the rescue.

The researchers who compiled the neighborhood-by-neighborhood data for metro Atlanta and other areas of the U.S. are probably more concerned with the policy issue than with fueling neighborhood envy, but it's useful for both. The authors call it the most comprehensive study to date of the affordability of housing and transportation. Other data that Web site viewers can compare include the number of cars per household, the cost of owning or renting, and average block size.

Transit advocates put it together: the Center for Neighborhood Technology and the Center for Transit Oriented Development, with funding from the Brookings Institution. Those organizations try to show connections between the housing people choose, the transportation they use and the environment: that buying a house in the boonies might bring a lower mortgage, but once gas and car costs are figured in, the financial advantage erodes.

That may bear out with a quick glance over the map. In huge swaths of the metro area, more than 20 percent of the income earned in a neighborhood goes to transportation, but not in downtown or midtown Atlanta.

KNOWING YOUR NEIGHBORHOODS

http://htaindex.cnt.org/map_tool

• Under "region," select Atlanta.

• Under "themes," click advanced.

• On the left-hand rail, click whatever data you're interested in.

• To zoom in and out on specific neighborhoods or move around the map, use the navigation tools on the upper left hand corner of the map. It's not possible to word-search neighborhoods and streets.

• To get actual data, click once on the place on the map you're interested in, and a window should pop up with the figures for that neighborhood.