Cell resolution and g.region?

[Steven Rose]

Hi!  I'm new to GRASS and have tried to read all I could about cell 
size, g.region, r.resample, r.neighbor etc, but am still not clear 
about what happends to my raster maps when I change the cell size 
using g.region.

I have a large database of 10m x 10m cells.  Usually I need the fine 
resolution to capture important, but narrow, ripparian strips.  
However, due to size of the database this fine resolution causes 
problems re processing speeds.  When I change the cell resolution 
using g.region (to say 100m x 100m cells) I can see the resolution 
change using d.rast for example, but I'm not sure of how GRASS is 
getting it's results.  The Grass beginners guide says it's using a 
nearest neighbour approach and r.resample refers me to r.neighbor, 
but this command wants to know what method to use (e.g. average, 
mode, etc) and how big the filter size is (as an odd number).  Since 
I don't specify any of this when simply changing the cell resolution 
in g.region, what is GRASS doing?  It is very important for my 
research that I understand this process.  

Any suggestions or pointers to more documentation/tutorials that will 
make this clear would be most appreciated.
Professor Steven Rose, R.P.F.       Phone: (705) 324-9144
Sir Sandford Fleming College        FAX:   (705) 878-9312
PO Box 8000, Lindsay,               Internet: srose at flemingc.on.ca
Ontario, CANADA K9V 5E6