Tuesday, 2 August 2011

Plotting aggregated points over Google Earth satellite images

Olly has created a web interface that plots our data on to Google Earth satellite images. Our data is aggregated to the centre of BNG 1km squares to preserve confidentiality and to standardise the resolution of our database as there are several different data sources to compare. I am concerned that end users may forget / not read the project documentation and think that a point marks the exact location of data when in reality it could be anywhere in a km square around the point.  Does anyone else share these concerns - or have a way of reminding an end user of this?


1 comment:

  1. Can you make the marker not be like a pinpoint but a blob/circle that is about a km in size? Or actually draw it has a polygon rather than a point. It depends what system you are using. It sounds like the Google Maps API. You might need more control from something like OpenLayers.
    If you have blobss in every cell of an invisible grid, then it becomes clear how detailed the data is. See for example the Placr crime data map. http://apps.placr.co.uk/crime/

    The other alternative is just to have text at the same of the map for a reminder.

    Is there a live demo we can look at online, or at least screenshots?