Could someone please explain to me the advantages and disadvantages of
using binned averages for reducing noise in ecological data?

By "binned average" I mean plotting the mean of one variable within binned
values of another variable.  This technique often reveals underlying
patterns in data that are otherwise hidden by lots of 'noise'.  I have seen
it used to relate catchment area to average catchment gradient,
demonstrating that there is an underlying linear relationship between the
two variables, and that the relationship changes in different geoclimatic
settings.

I have also seen it used to relate canopy height to hillslope position (ie
distance from stream or elevation above stream).  But I am concerned that
in this instance the data may merely be reflecting spatial autocorrelation,
as they come from adjacent cells on a remotely sensed image.  (Whereas the
catchment data are from discrete, geographically separated areas).

I am sceptical about the canopy height data as it relates to an extremely
flat area in semi-arid savanna, where I suspect that canopy height is more
likely to be a function of fire history than of topographically controlled
access to water.

Can anyone help?  Id appreciate your thoughts!

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