Regional Prominence cutoffs

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Regional Prominence cutoffs

Postby Matt Lemke » Sun Apr 08, 2012 8:24 pm

John,
When I am looking at lists for places throughout the country I noticed you do not have a way to change the prominence cutoff.
I'm not sure if you have climbed in other states but in Washington, a peak needs to have 400 feet of prominence to be considered ranked.
There are also the exceptions on the volcanoes where 800 feet of prominence is required.

I guess what I am trying to say is that in other states, the highest 100 or highest 50 or whatever isn't determined by the 300 foot prominence rule and I was wondering if there
is a way to have an option to change the prominence cutoff. Climbers in WA almost always go for the "Bulger List" as I am for the WA top 100.
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Re: Regional Prominence cutoffs

Postby RyanSchilling » Tue Apr 10, 2012 5:02 pm

To an extent, this functionality is already built-in. If you generate the list of 8ers in Washington, this is the link:

http://listsofjohn.com/PeakStats/select ... =&S=WA&R=8


It's easy to change the threshold to 400' by modifying the 'P=300' portion of the URL:

http://listsofjohn.com/PeakStats/select ... =&S=WA&R=8


John also has an interface for setting your own prominence threshold:

http://listsofjohn.com/PeakStats/select.php?S=WA



Tadaa!

Alternatively (or additionally) you can use custom lists to show only those peaks that meet your criteria.
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Re: Regional Prominence cutoffs

Postby Matt Lemke » Fri Apr 13, 2012 9:17 pm

Hey thanks man! I guess I just didn't know how to do that :oops:
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Re: Regional Prominence cutoffs

Postby EricNoel » Wed Apr 25, 2012 9:11 am

One thing to bear in mind is that the Bulgers list is ostensibly a highest peaks list but it is really a club list so to speak. Most folks don't do a true P400 100 highest WA list because it means doing Lincoln. There is no possible cutoff that could be used that would generate that Bulger list and because of the way it treats named peaks and volcanic summits you wind up with a situation where higher and more prominent peaks are omitted in favor of lower and less prominent peaks (eg Liberty Cap versus Horseshoe). Don't get me wrong, it is an excellent list and worthy of its popularity but the standards used to generate it are a bit silly.

Check out this handy page that John Roper put together that gives both lists as well as other cutoffs that could be used to generate a 100 Highest Peaks list:
http://www.rhinoclimbs.com/documents/ListofPromLists.rc_001.swf
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Re: Regional Prominence cutoffs

Postby Swithich » Thu Apr 26, 2012 11:52 am

Then there is also the issue of more precise prominence thresholds aka clean prominence with 40 foot contours and clean prominence with 20 foot contours. The Howbert list adds 9 mountains if you use the more precise contour measures.

Oh well, more mountains to do.

-Swithich
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Re: Regional Prominence cutoffs

Postby RyanSchilling » Fri Apr 27, 2012 10:52 am

Then there is also the issue of more precise prominence thresholds aka clean prominence with 40 foot contours and clean prominence with 20 foot contours. The Howbert list adds 9 mountains if you use the more precise contour measures.


I've seen plenty of arguments for "clean prominence," but precision has never been one of them. With rare exceptions, clean prominence underestimates the true prominence of a peak. Isn't the idea that, worst-case-scenario, the prominence of a peak can be no less than its clean prominence?
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Re: Regional Prominence cutoffs

Postby Swithich » Fri Apr 27, 2012 6:49 pm

RyanSchilling wrote:
Then there is also the issue of more precise prominence thresholds aka clean prominence with 40 foot contours and clean prominence with 20 foot contours. The Howbert list adds 9 mountains if you use the more precise contour measures.


I've seen plenty of arguments for "clean prominence," but precision has never been one of them. With rare exceptions, clean prominence underestimates the true prominence of a peak. Isn't the idea that, worst-case-scenario, the prominence of a peak can be no less than its clean prominence?


I'm not arguing for or against it...just pointing out an issue that has recently surfaced. That is you have to revise your list if sharper maps come out. The Howbert list was created in 1995 I believe and used clean prominence. The issue was standard maps back then (and still now) use a 40 foot contour interval. But as maps have improved, I've seen maps with 20 foot contour intervals (like the ones used on listsofjohn). I'm simply pointing out that a list may change simply because new maps may rule peaks to have the prominence that the courser maps could not determine (via clean prominence).

All I'm saying is you shouldn't get too attached to a list. Lists are nice for completing, but they can change. AKA the Howbert list which had nine peaks added via the sharper contour intervals.

-Swithich
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Re: Regional Prominence cutoffs

Postby RyanSchilling » Tue May 01, 2012 9:20 am

Ah, thanks for clarifying. I understand you now.
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Re: Regional Prominence cutoffs

Postby hikenewhampshire » Tue Jun 26, 2012 4:47 pm

I didn't realize that you could edit the URL like that, now I need to figure out the SQL injection to read credit card nos :-)

Note that this method works only for p >= 300, as the database doesn't contain unnamed peaks with p < 300 they can't appear on generated lists
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