deepest, shallowest, average

Dirk Hohndel dirk at
Mon Jun 9 18:56:13 PDT 2014

This email will make some old-timers giggle.
We've had this discussion quite a few times. At least three or four times
a year it seems like.

And after resoundingly defending our nomenclature for many years I think
I'm finally coming around.

Should we change the meaning of the "average" depth?

Deepest and shallowest are about the max depth of the dives that are

Average right now is the average depth of all the dives - not the average
of all the deepest depths. From a mathematical point of view this makes
perfect sense. But it is extremely unintuitive - especially when the
average frequently is less than the minimum :-/

So should we consider changing this for 4.2?

And if we do, what should be the algorithm for average?

Add the max depth for each dive and divide by number of dives?
Do a weighted average by time (this doesn't really make sense, now that I
write it down - just because the overall dive was longer doesn't mean that
it's "depth value" should count more.

Or should we just drop the average for depth because it's so ill defined?

Opinions, please


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