[Buildingdata] Re: outliers

[Andy Turner]

This may be equivalent to your horrible hack, but one can truncate (as in a
truncated mean statistics) as follows: Calculate the centroid of all the
points, calculate the distance to all points from this centroid, discount
say the 5% of the furthest away points, recalculate the bounding box (or
circle or whatever you are using) for the remaining points and use this.
This could be computationally slow if you are doing it lots of times, and
setting the threshold is arbitrary, but this could work. There are various
ways to speed this up, for instance you could simply use the centroid of
each of the buildings rather than each of their complete geometries. HTH
Andy


On Tue, Apr 16, 2013 at 10:29 AM, Christopher Gutteridge <
cjg at ecs.soton.ac.uk> wrote:

> So I've got a situation. On our main campus, the database lists two
> buildings as part of that site, although they are quite a way off the
> main site and really screw up any automatic map renderings as they cause
> the important part to shrink when scaled-to-fit.
>
> The ideal solution is to have better data, but I am not allowed to edit
> what estates send me, although I can augment it.
>
> I currently remove them with an awful hack in the code, but what I'm
> thinking is creating a relationship between a thing and seomthing it's
> listed as having within, but should not be included on the default map. eg.
>
> <http://id.southampton.ac.uk/site/1> hasOutlier
> <http://id.southampton.ac.uk/building/1580> .
>
> Any thoughts?
>
> --
> Christopher Gutteridge -- http://users.ecs.soton.ac.uk/cjg
>
> University of Southampton Open Data Service:
> http://data.southampton.ac.uk/
> You should read the ECS Web Team blog:
> http://blogs.ecs.soton.ac.uk/webteam/
>
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