Loading ...
Sorry, an error occurred while loading the content.

Re: Prominence

Expand Messages
  • gregslayden
    Hi, Petter (and rest of Prominence e-group), Yes, the policy for Peakbagger.com is to use clean prominence values throughout the site. I am sure there have
    Message 1 of 13 , Nov 1, 2011
    • 0 Attachment
      Hi, Petter (and rest of Prominence e-group),

      Yes, the policy for Peakbagger.com is to use clean prominence values throughout the site.

      I am sure there have been many discussions about this topic over the years. I prefer clean to interpolated because clean will never overstate a prominence--there is almost zero probability that a peak on a clean P600m list will have less than the stated list prominence value. I guess my conservative nature does not like any false positives, at the cost of perhaps losing some valid list members.

      I do understand all the arguments for interpolated, and I think it is mostly a matter of preference. Was there ever a poll in this e-group on this issue? Did one side or the other have a clear majority? (Also--does anyone pefer optimistic ["dirty"] prominence?)

      In the Peakbagger database, the goal is to store the contour intervals for all summits and cols that don't have exact elevations on topo maps. Most USA peaks have the contour intervals stored, and I am slowly working on other countries with good online mapping available (Norway, Spain, France, etc.) but coverage is spotty.

      Currently, this allows prominence lists on the site to show "error range" peaks below the clean prom thereshold as "unranked" peaks on a list, so at least I am reporting them for those interested.

      This also means I certainly could change the site easily to start using interpolated (or optimistic) prominence, and perhaps allow that to be a user-selected setting--all lists would be altered to include/exclude peaks based on your preferred setting. I can look into implementing this at some point.

      The main problem is that if I prefer a "clean" list and Petter prefers an "interpolated" list, we are really working on 2 different lists, and tracking the FRL and other metrics becomes problematical. So for these purposes, a standard is required. If a clear majority of prom enthusiasts is for interpolated, I will certainly consider changing the list definiton metric on the site.

      Thanks,
      --Greg




      --- In prominence@yahoogroups.com, Petter Bjorstad <Petter.Bjorstad@...> wrote:
      >
      > Hi Greg,
      >
      > This is an old topic, but I realize that I do not know
      > what policy you actually use.
      >
      > Interpolated Prominence OR "clean" Prominence ??
      >
      > I observe on Norwegian Mountains like Store Hånosi,
      > that you give a prominence of 596 which is clean,
      > while I (on my pages and lists) assign 606 which is interpolated.
      >
      > The effect is, of course, that my lists of 600 meter prominence
      > will differ from yours..
      >
      > You obviously know (from previous discussions) that interpolated
      > prominence is far more likely to be "correct" than "clean", ie.
      > as accuracy improves your lists are more likely to be "wrong"
      > (in need of more corrections) than the interpolated lists.
      >
      > Have you been using "clean" consistently across all prominence based lists
      > on Peakbagger?
      >
      > Will you consider changing this policy? I guess the interpolated
      > values and lists are gaining more popularity. The main annoying
      > thing is just that lists read differently.
      >
      > You have me at 461 P600 peaks, while I have listed 466 peaks on
      > my own lists..
      >
      > Hope you are doing well,
      > I was just a trip in California and visited 5 P600
      > tops in Mendocino in the weekend.
      >
      > Best regards
      > Petter
      >
    • Adam Helman
      Please read this web page to aid in deciding what kind of cutoff definition is preferred - http://www.cohp.org/prominence/cutoff_definitions.html Adam Helman
      Message 2 of 13 , Nov 1, 2011
      • 0 Attachment
        Please read this web page to aid in deciding what kind of cutoff definition is preferred -

        http://www.cohp.org/prominence/cutoff_definitions.html

        Adam Helman

        ----- Original Message -----
        From: gregslayden
        To: prominence@yahoogroups.com
        Sent: Tuesday, November 01, 2011 11:04 AM
        Subject: [prominence] Re: Prominence



        Hi, Petter (and rest of Prominence e-group),

        Yes, the policy for Peakbagger.com is to use clean prominence values throughout the site.

        I am sure there have been many discussions about this topic over the years. I prefer clean to interpolated because clean will never overstate a


        [Non-text portions of this message have been removed]
      • Petter Bjorstad
        Hi Greg, Thanks for a very clear and concise reply. Let me first give you and Peakbagger a BIG hand for all the good work, in particular, also recent updates
        Message 3 of 13 , Nov 1, 2011
        • 0 Attachment
          Hi Greg,

          Thanks for a very clear and concise reply.

          Let me first give you and Peakbagger a BIG hand for all the good work,
          in particular, also recent updates that certainly shows that Peakbagger
          follows important trends as technology facilitates more advances.
          I keep an eye on pages like http://peakbook.org , it is a pretty "modern"
          design with pictures, trip reports, lists, multi-language support etc..
          It currently falls behind on the degree of coverage and having a much less
          international user base. Again, your work is greatly appreciated!!

          The fact that you give lower/upper contours where spot elevations are missing,
          ie. of almost all key saddles, is also "WAY TO GO".
          In fact, I find the information about prominences of peaks to be more comprehensive
          and reliable on Peakbagger than on any other Internet site.

          I discovered your clean prominence practice when I noted that the number of peaks
          climbed on some of my lists deviated from your lists. As there will be multiple
          lists around, I also obviously agree that it would have been "best" but possibly not
          so easily achieved, if lists used a consistent definition. There are TWO issues,
          the ORDER of the peaks in a list, and how to establish the correct CUTOFF.

          One may in fact argue, that the order is perhaps even more important than the cut.
          Now, as accuracy improves, the order that follows from an interpolated based list is
          going to be MORE correct (ie. in need for fewer interchanges), than a list based
          on "clean" prominence. For the majority of peaks this is not a question of making the
          list or not, but to establish the best possible (given the available data) order.

          The cutoff zone of a list can always be arranged in such a way that one sees which peaks
          fall below the clean treshold, but remain on the list within the zone of uncertainty.
          When it the comes to stating say, how many P600 have you climbed? Then I prefer to
          report all P600 above the interpolated cutoff. Say I have climbed 300 P600 based on
          clean, then an additional 10 within "optimistic" of which 4 are within "interpolated".
          I will then state that I have climbed 304 P600 peaks. This figure is likely to be more
          correct than either 300 or 310.

          Best regards,

          Petter
        • Adam Helman
          I think the MAIN reason why clean prominence is so widespread in published lists is because of historical precedent : it was only much later I demonstrated
          Message 4 of 13 , Nov 1, 2011
          • 0 Attachment
            I think the MAIN reason why "clean" prominence is so widespread in published lists
            is because of historical precedent : it was only much later I demonstrated that a
            list based on interpolated prominence is more accurate, i.e., correctly placing 75% of
            "gray-zone" peaks as either "on" or "off" a given list of specified cutoff value.

            I should post my PROOF of that claim at some point.... in the meantime please
            just have faith in it!!

            (Stated differently, there was INITIALLY no reason to discredit clean prominence. Now there IS.)

            *************************************************************************

            I agree with Petter that it's disconcerting to compare two prominence lists and find
            that the ORDER differs of ranked peaks - and it's generally because map contour intervals
            are not identical for all summits and their key saddles (else there would be an IDENTICAL
            shift "up" or "down" of values for clean and interpolated tables - the ORDERING being uneffected).

            I also think of my P600m count (actually, P2000 foot count) as the sum of
            the clean count plus exactly one-half the gray-zone count. THAT way, in a statistical sense
            of long-term averaging, the final count should be closer to my unknowable "true" count
            than just using clean values.

            Adam Helman



            ----- Original Message -----
            From: Petter Bjorstad
            To: prominence@yahoogroups.com
            Sent: Tuesday, November 01, 2011 11:41 AM
            Subject: Re: [prominence] Re: Prominence



            Hi Greg,

            Thanks for a very clear and concise reply.

            Let me first give you and Peakbagger a BIG hand for all the good work,
            in particular, also recent updates that certainly shows that Peakbagger
            follows important trends as technology facilitates more advances.
            I keep an eye on pages like http://peakbook.org , it is a pretty "modern"
            design with pictures, trip reports, lists, multi-language support etc..
            It currently falls behind on the degree of coverage and having a much less
            international user base. Again, your work is greatly appreciated!!

            The fact that you give lower/upper contours where spot elevations are missing,
            ie. of almost all key saddles, is also "WAY TO GO".
            In fact, I find the information about prominences of peaks to be more comprehensive
            and reliable on Peakbagger than on any other Internet site.

            I discovered your clean prominence practice when I noted that the number of peaks
            climbed on some of my lists deviated from your lists. As there will be multiple
            lists around, I also obviously agree that it would have been "best" but possibly not
            so easily achieved, if lists used a consistent definition. There are TWO issues,
            the ORDER of the peaks in a list, and how to establish the correct CUTOFF.

            One may in fact argue, that the order is perhaps even more important than the cut.
            Now, as accuracy improves, the order that follows from an interpolated based list is
            going to be MORE correct (ie. in need for fewer interchanges), than a list based
            on "clean" prominence. For the majority of peaks this is not a question of making the
            list or not, but to establish the best possible (given the available data) order.

            The cutoff zone of a list can always be arranged in such a way that one sees which peaks
            fall below the clean treshold, but remain on the list within the zone of uncertainty.
            When it the comes to stating say, how many P600 have you climbed? Then I prefer to
            report all P600 above the interpolated cutoff. Say I have climbed 300 P600 based on
            clean, then an additional 10 within "optimistic" of which 4 are within "interpolated".
            I will then state that I have climbed 304 P600 peaks. This figure is likely to be more
            correct than either 300 or 310.

            Best regards,

            Petter



            ------------------------------------------------------------------------------

            No virus found in this message.
            Checked by AVG - www.avg.com
            Version: 10.0.1411 / Virus Database: 2092/3989 - Release Date: 11/01/11


            [Non-text portions of this message have been removed]
          • Rob Woodall
            I too prefer interpolated to clean prominence for the reasons stated by Petter and Adam. UK prom lists go a bit further and use estimated prominence rather
            Message 5 of 13 , Nov 1, 2011
            • 0 Attachment
              I too prefer interpolated to clean prominence for the reasons stated by
              Petter and Adam.

              UK prom lists go a bit further and use estimated prominence rather than
              interpolated; i.e. if the saddle is just below the 500m contour (looks like
              499m) and the summit just above 550 (looks like 551m) we would call it P52,
              not P60 (interpolated) nor P50 (clean).

              It occurs to me that the Marilyns (Great Britain P150m summits) total was
              1552 in 1999 and seems to stay around that figure, +/- about 2 despite a
              lot of survey effort including differential GPS in recent years. Peaks are
              promoted, peaks are demoted but the total stays about the same.

              Rob

              On Tue, Nov 1, 2011 at 6:55 PM, Adam Helman <helman@...> wrote:

              > **
              >
              >
              > I think the MAIN reason why "clean" prominence is so widespread in
              > published lists
              > is because of historical precedent : it was only much later I demonstrated
              > that a
              > list based on interpolated prominence is more accurate, i.e., correctly
              > placing 75% of
              > "gray-zone" peaks as either "on" or "off" a given list of specified cutoff
              > value.
              >
              > I should post my PROOF of that claim at some point.... in the meantime
              > please
              > just have faith in it!!
              >
              > (Stated differently, there was INITIALLY no reason to discredit clean
              > prominence. Now there IS.)
              >
              > *************************************************************************
              >
              > I agree with Petter that it's disconcerting to compare two prominence
              > lists and find
              > that the ORDER differs of ranked peaks - and it's generally because map
              > contour intervals
              > are not identical for all summits and their key saddles (else there would
              > be an IDENTICAL
              > shift "up" or "down" of values for clean and interpolated tables - the
              > ORDERING being uneffected).
              >
              > I also think of my P600m count (actually, P2000 foot count) as the sum of
              > the clean count plus exactly one-half the gray-zone count. THAT way, in a
              > statistical sense
              > of long-term averaging, the final count should be closer to my unknowable
              > "true" count
              > than just using clean values.
              >
              > Adam Helman
              >
              >
              > ----- Original Message -----
              > From: Petter Bjorstad
              > To: prominence@yahoogroups.com
              > Sent: Tuesday, November 01, 2011 11:41 AM
              > Subject: Re: [prominence] Re: Prominence
              >
              > Hi Greg,
              >
              > Thanks for a very clear and concise reply.
              >
              > Let me first give you and Peakbagger a BIG hand for all the good work,
              > in particular, also recent updates that certainly shows that Peakbagger
              > follows important trends as technology facilitates more advances.
              > I keep an eye on pages like http://peakbook.org , it is a pretty "modern"
              > design with pictures, trip reports, lists, multi-language support etc..
              > It currently falls behind on the degree of coverage and having a much less
              > international user base. Again, your work is greatly appreciated!!
              >
              > The fact that you give lower/upper contours where spot elevations are
              > missing,
              > ie. of almost all key saddles, is also "WAY TO GO".
              > In fact, I find the information about prominences of peaks to be more
              > comprehensive
              > and reliable on Peakbagger than on any other Internet site.
              >
              > I discovered your clean prominence practice when I noted that the number
              > of peaks
              > climbed on some of my lists deviated from your lists. As there will be
              > multiple
              > lists around, I also obviously agree that it would have been "best" but
              > possibly not
              > so easily achieved, if lists used a consistent definition. There are TWO
              > issues,
              > the ORDER of the peaks in a list, and how to establish the correct CUTOFF.
              >
              > One may in fact argue, that the order is perhaps even more important than
              > the cut.
              > Now, as accuracy improves, the order that follows from an interpolated
              > based list is
              > going to be MORE correct (ie. in need for fewer interchanges), than a list
              > based
              > on "clean" prominence. For the majority of peaks this is not a question of
              > making the
              > list or not, but to establish the best possible (given the available data)
              > order.
              >
              > The cutoff zone of a list can always be arranged in such a way that one
              > sees which peaks
              > fall below the clean treshold, but remain on the list within the zone of
              > uncertainty.
              > When it the comes to stating say, how many P600 have you climbed? Then I
              > prefer to
              > report all P600 above the interpolated cutoff. Say I have climbed 300 P600
              > based on
              > clean, then an additional 10 within "optimistic" of which 4 are within
              > "interpolated".
              > I will then state that I have climbed 304 P600 peaks. This figure is
              > likely to be more
              > correct than either 300 or 310.
              >
              > Best regards,
              >
              > Petter
              >
              > ----------------------------------------------------------
              >
              > No virus found in this message.
              > Checked by AVG - www.avg.com
              > Version: 10.0.1411 / Virus Database: 2092/3989 - Release Date: 11/01/11
              >
              > [Non-text portions of this message have been removed]
              >
              >
              >


              [Non-text portions of this message have been removed]
            • Adam Helman
              ... That s the long-term statistical averaging effect, Rob, that I employ as basis for estimating my prominence totals. In the long-run it s guaranteed that
              Message 6 of 13 , Nov 1, 2011
              • 0 Attachment
                > It occurs to me that the Marilyns (Great Britain P150m summits) total was
                > 1552 in 1999 and seems to stay around that figure, +/- about 2 despite a
                > lot of survey effort including differential GPS in recent years. Peaks are
                > promoted, peaks are demoted but the total stays about the same.

                That's the "long-term statistical averaging" effect, Rob, that I employ
                as basis for estimating my prominence totals. In the long-run it's
                guaranteed
                that "heads" and "tails" will each occur 50% of the time.

                Adam H.

                ----- Original Message -----
                From: "Rob Woodall" <rhwxyz@...>
                To: <prominence@yahoogroups.com>
                Sent: Tuesday, November 01, 2011 12:43 PM
                Subject: Re: [prominence] Prominence


                >I too prefer interpolated to clean prominence for the reasons stated by
                > Petter and Adam.
                >
              • Eric Noel
                Have you ever been asked to guess an adult s age? If so, you might have come up with a number and then guessed something a bit lower because guessing too high
                Message 7 of 13 , Nov 1, 2011
                • 0 Attachment
                  Have you ever been asked to guess an adult's age? If so, you might have come up with a number and then guessed something a bit lower because guessing too high has a certain negative insulting implication to it that does not occur if you guess too low. That is to say, there are social/psychological aspects that make an outcome on one side of the "best estimate" less desirable than one on the other side.

                  To me, that is the aspect that Greg mentioned which seems to resonate with some folks but has no value to others. Some people prefer the most mathematically valid estimate, which is fine, but others would prefer to tread cautiously and err on the downside in terms of counts or list inclusion (via dirty prom).

                  Using Petter's handy example, let us suppose that his "true" P600m peak count is 303. Is it better to use a mean best guess estimate of 304 and overstate his count his by 1 or is it better to estimate just the 300 clean and undercount by 3? I'm sure that many would prefer the more accurate estimate of 304. In that position, I'd be partial to the 300 count myself because I would rather lose credit for something accomplished in those 3 error range peaks tagged than to take credit for something not accomplished in the 1 that isn't a P600 in this example. The latter outcome is preferable even if less accurate. People of a certain sensibility just have that preference to be conservative in their estimates. To each (webmaster) his own I guess. Ideally, I want my peak counts in clean prom and my list completion cutoffs in dirty prom with all peak rivalries included. That's just what Greg does currently and because of that approach users can be pretty confident
                  than neither peak counts nor list completions are overstated to confer a false positive as would happen much more often if one uses mean prom.

                  -Eric


                  --- On Tue, 11/1/11, Adam Helman <helman@...> wrote:

                  From: Adam Helman <helman@...>
                  Subject: [prominence] Prominence
                  To: prominence@yahoogroups.com
                  Date: Tuesday, November 1, 2011, 11:55 AM
















                   









                  I think the MAIN reason why "clean" prominence is so widespread in published lists

                  is because of historical precedent : it was only much later I demonstrated that a

                  list based on interpolated prominence is more accurate, i.e., correctly placing 75% of

                  "gray-zone" peaks as either "on" or "off" a given list of specified cutoff value.



                  I should post my PROOF of that claim at some point.... in the meantime please

                  just have faith in it!!



                  (Stated differently, there was INITIALLY no reason to discredit clean prominence. Now there IS.)



                  *************************************************************************



                  I agree with Petter that it's disconcerting to compare two prominence lists and find

                  that the ORDER differs of ranked peaks - and it's generally because map contour intervals

                  are not identical for all summits and their key saddles (else there would be an IDENTICAL

                  shift "up" or "down" of values for clean and interpolated tables - the ORDERING being uneffected).



                  I also think of my P600m count (actually, P2000 foot count) as the sum of

                  the clean count plus exactly one-half the gray-zone count. THAT way, in a statistical sense

                  of long-term averaging, the final count should be closer to my unknowable "true" count

                  than just using clean values.



                  Adam Helman



                  ----- Original Message -----

                  From: Petter Bjorstad

                  To: prominence@yahoogroups.com

                  Sent: Tuesday, November 01, 2011 11:41 AM

                  Subject: Re: [prominence] Re: Prominence



                  Hi Greg,



                  Thanks for a very clear and concise reply.



                  Let me first give you and Peakbagger a BIG hand for all the good work,

                  in particular, also recent updates that certainly shows that Peakbagger

                  follows important trends as technology facilitates more advances.

                  I keep an eye on pages like http://peakbook.org , it is a pretty "modern"

                  design with pictures, trip reports, lists, multi-language support etc..

                  It currently falls behind on the degree of coverage and having a much less

                  international user base. Again, your work is greatly appreciated!!



                  The fact that you give lower/upper contours where spot elevations are missing,

                  ie. of almost all key saddles, is also "WAY TO GO".

                  In fact, I find the information about prominences of peaks to be more comprehensive

                  and reliable on Peakbagger than on any other Internet site.



                  I discovered your clean prominence practice when I noted that the number of peaks

                  climbed on some of my lists deviated from your lists. As there will be multiple

                  lists around, I also obviously agree that it would have been "best" but possibly not

                  so easily achieved, if lists used a consistent definition. There are TWO issues,

                  the ORDER of the peaks in a list, and how to establish the correct CUTOFF.



                  One may in fact argue, that the order is perhaps even more important than the cut.

                  Now, as accuracy improves, the order that follows from an interpolated based list is

                  going to be MORE correct (ie. in need for fewer interchanges), than a list based

                  on "clean" prominence. For the majority of peaks this is not a question of making the

                  list or not, but to establish the best possible (given the available data) order.



                  The cutoff zone of a list can always be arranged in such a way that one sees which peaks

                  fall below the clean treshold, but remain on the list within the zone of uncertainty.

                  When it the comes to stating say, how many P600 have you climbed? Then I prefer to

                  report all P600 above the interpolated cutoff. Say I have climbed 300 P600 based on

                  clean, then an additional 10 within "optimistic" of which 4 are within "interpolated".

                  I will then state that I have climbed 304 P600 peaks. This figure is likely to be more

                  correct than either 300 or 310.



                  Best regards,



                  Petter



                  ----------------------------------------------------------



                  No virus found in this message.

                  Checked by AVG - www.avg.com

                  Version: 10.0.1411 / Virus Database: 2092/3989 - Release Date: 11/01/11



                  [Non-text portions of this message have been removed]



























                  [Non-text portions of this message have been removed]
                • Rob Woodall
                  Eric s very valid observations again take me back to my Marilyns list. The latest Hall of Fame (note the British sense of irony!) total shows my total and that
                  Message 8 of 13 , Nov 1, 2011
                  • 0 Attachment
                    Eric's very valid observations again take me back to my Marilyns list. The
                    latest Hall of Fame (note the British sense of irony!) total shows my total
                    and that of several others as -2 compared with the last published figures.
                    This doesn't of course mean that I'd claimed to have climbed 2 peaks which
                    I haven't, but that 2 peaks I've climbed have been demoted thru more
                    accurate info (and that in the meantime we still haven't had the right
                    conditions to climb the remaining 2 sea stacks). I'm comfortable with that
                    -2
                    For practical purposes Peakbagger's current methodology is perfectly OK as
                    it's easy to (mentally or otherwise) add on the error range peaks to one's
                    total.
                    Rob
                    On Tue, Nov 1, 2011 at 8:09 PM, Eric Noel <ericjnoel@...> wrote:

                    > **
                    >
                    >
                    > Have you ever been asked to guess an adult's age? If so, you might have
                    > come up with a number and then guessed something a bit lower because
                    > guessing too high has a certain negative insulting implication to it that
                    > does not occur if you guess too low. That is to say, there are
                    > social/psychological aspects that make an outcome on one side of the "best
                    > estimate" less desirable than one on the other side.
                    >
                    > To me, that is the aspect that Greg mentioned which seems to resonate with
                    > some folks but has no value to others. Some people prefer the most
                    > mathematically valid estimate, which is fine, but others would prefer to
                    > tread cautiously and err on the downside in terms of counts or list
                    > inclusion (via dirty prom).
                    >
                    > Using Petter's handy example, let us suppose that his "true" P600m peak
                    > count is 303. Is it better to use a mean best guess estimate of 304 and
                    > overstate his count his by 1 or is it better to estimate just the 300 clean
                    > and undercount by 3? I'm sure that many would prefer the more accurate
                    > estimate of 304. In that position, I'd be partial to the 300 count myself
                    > because I would rather lose credit for something accomplished in those 3
                    > error range peaks tagged than to take credit for something not accomplished
                    > in the 1 that isn't a P600 in this example. The latter outcome is
                    > preferable even if less accurate. People of a certain sensibility just have
                    > that preference to be conservative in their estimates. To each (webmaster)
                    > his own I guess. Ideally, I want my peak counts in clean prom and my list
                    > completion cutoffs in dirty prom with all peak rivalries included. That's
                    > just what Greg does currently and because of that approach users can be
                    > pretty confident
                    > than neither peak counts nor list completions are overstated to confer a
                    > false positive as would happen much more often if one uses mean prom.
                    >
                    > -Eric
                    >
                    > --- On Tue, 11/1/11, Adam Helman <helman@...> wrote:
                    >
                    > From: Adam Helman <helman@...>
                    > Subject: [prominence] Prominence
                    > To: prominence@yahoogroups.com
                    > Date: Tuesday, November 1, 2011, 11:55 AM
                    >
                    >
                    >
                    >
                    > I think the MAIN reason why "clean" prominence is so widespread in
                    > published lists
                    >
                    > is because of historical precedent : it was only much later I demonstrated
                    > that a
                    >
                    > list based on interpolated prominence is more accurate, i.e., correctly
                    > placing 75% of
                    >
                    > "gray-zone" peaks as either "on" or "off" a given list of specified cutoff
                    > value.
                    >
                    > I should post my PROOF of that claim at some point.... in the meantime
                    > please
                    >
                    > just have faith in it!!
                    >
                    > (Stated differently, there was INITIALLY no reason to discredit clean
                    > prominence. Now there IS.)
                    >
                    > *************************************************************************
                    >
                    > I agree with Petter that it's disconcerting to compare two prominence
                    > lists and find
                    >
                    > that the ORDER differs of ranked peaks - and it's generally because map
                    > contour intervals
                    >
                    > are not identical for all summits and their key saddles (else there would
                    > be an IDENTICAL
                    >
                    > shift "up" or "down" of values for clean and interpolated tables - the
                    > ORDERING being uneffected).
                    >
                    > I also think of my P600m count (actually, P2000 foot count) as the sum of
                    >
                    > the clean count plus exactly one-half the gray-zone count. THAT way, in a
                    > statistical sense
                    >
                    > of long-term averaging, the final count should be closer to my unknowable
                    > "true" count
                    >
                    > than just using clean values.
                    >
                    > Adam Helman
                    >
                    > ----- Original Message -----
                    >
                    > From: Petter Bjorstad
                    >
                    > To: prominence@yahoogroups.com
                    >
                    > Sent: Tuesday, November 01, 2011 11:41 AM
                    >
                    > Subject: Re: [prominence] Re: Prominence
                    >
                    > Hi Greg,
                    >
                    > Thanks for a very clear and concise reply.
                    >
                    > Let me first give you and Peakbagger a BIG hand for all the good work,
                    >
                    > in particular, also recent updates that certainly shows that Peakbagger
                    >
                    > follows important trends as technology facilitates more advances.
                    >
                    > I keep an eye on pages like http://peakbook.org , it is a pretty "modern"
                    >
                    > design with pictures, trip reports, lists, multi-language support etc..
                    >
                    > It currently falls behind on the degree of coverage and having a much less
                    >
                    > international user base. Again, your work is greatly appreciated!!
                    >
                    > The fact that you give lower/upper contours where spot elevations are
                    > missing,
                    >
                    > ie. of almost all key saddles, is also "WAY TO GO".
                    >
                    > In fact, I find the information about prominences of peaks to be more
                    > comprehensive
                    >
                    > and reliable on Peakbagger than on any other Internet site.
                    >
                    > I discovered your clean prominence practice when I noted that the number
                    > of peaks
                    >
                    > climbed on some of my lists deviated from your lists. As there will be
                    > multiple
                    >
                    > lists around, I also obviously agree that it would have been "best" but
                    > possibly not
                    >
                    > so easily achieved, if lists used a consistent definition. There are TWO
                    > issues,
                    >
                    > the ORDER of the peaks in a list, and how to establish the correct CUTOFF.
                    >
                    > One may in fact argue, that the order is perhaps even more important than
                    > the cut.
                    >
                    > Now, as accuracy improves, the order that follows from an interpolated
                    > based list is
                    >
                    > going to be MORE correct (ie. in need for fewer interchanges), than a list
                    > based
                    >
                    > on "clean" prominence. For the majority of peaks this is not a question of
                    > making the
                    >
                    > list or not, but to establish the best possible (given the available data)
                    > order.
                    >
                    > The cutoff zone of a list can always be arranged in such a way that one
                    > sees which peaks
                    >
                    > fall below the clean treshold, but remain on the list within the zone of
                    > uncertainty.
                    >
                    > When it the comes to stating say, how many P600 have you climbed? Then I
                    > prefer to
                    >
                    > report all P600 above the interpolated cutoff. Say I have climbed 300 P600
                    > based on
                    >
                    > clean, then an additional 10 within "optimistic" of which 4 are within
                    > "interpolated".
                    >
                    > I will then state that I have climbed 304 P600 peaks. This figure is
                    > likely to be more
                    >
                    > correct than either 300 or 310.
                    >
                    > Best regards,
                    >
                    > Petter
                    >
                    > ----------------------------------------------------------
                    >
                    > No virus found in this message.
                    >
                    > Checked by AVG - www.avg.com
                    >
                    > Version: 10.0.1411 / Virus Database: 2092/3989 - Release Date: 11/01/11
                    >
                    > [Non-text portions of this message have been removed]
                    >
                    > [Non-text portions of this message have been removed]
                    >
                    >
                    >


                    [Non-text portions of this message have been removed]
                  • A-P Fisher
                    Count one for preferring estimated prominence + margin of error. That is: do not neglect to mention that the estimated prominence list of Marilyns, and almost
                    Message 9 of 13 , Nov 1, 2011
                    • 0 Attachment
                      Count one for preferring estimated prominence + margin of error.

                      That is: do not neglect to mention that the estimated prominence
                      list of Marilyns, and almost all the other British Isles based lists
                      arising from RHB [book], rhb [mail-list], TACit Press, et al, have a
                      complimentary list of subs -- not to list all the additional summits
                      that would make the main list were it based on dirty prominence, but
                      beyond that to include (again by estimated prominence) those that
                      miss out on the main list by (typically) up to 10m. *

                      If I were going for a list completion, I'd not be too fussed about
                      when I'd made it to n-hundred undeniable tops, or whatever, but I'd
                      sure want to be as certain as reasonably possible that when I thought
                      I'd completed a theoretical list I'd almost certainly truly have done
                      so! **

                      A-P

                      Notes
                      * ... mind, as a celebrated group of peakbagging surveyors stalk the
                      British hills with their equipment, such large (for the standard of
                      mapping) margins of error are becoming redundant!
                      ** ... except, truth be told, I'm more interested in summiting the n
                      most prominent tops of the infinite list of whatever region, rather
                      than all those above so-many units of prominence.

                      On Tue, November 1, 2011 19:43, Rob Woodall wrote:
                      > I too prefer interpolated to clean prominence for the reasons stated by
                      > Petter and Adam.
                      >
                      > UK prom lists go a bit further and use estimated prominence rather than
                      > interpolated; i.e. if the saddle is just below the 500m contour (looks like
                      > 499m) and the summit just above 550 (looks like 551m) we would call it P52,
                      > not P60 (interpolated) nor P50 (clean).
                      >
                      > It occurs to me that the Marilyns (Great Britain P150m summits) total was
                      > 1552 in 1999 and seems to stay around that figure, +/- about 2 despite a
                      > lot of survey effort including differential GPS in recent years. Peaks are
                      > promoted, peaks are demoted but the total stays about the same.
                      >
                      > Rob
                      >
                      > On Tue, Nov 1, 2011 at 6:55 PM, Adam Helman <helman@...> wrote:
                      >
                      >> **
                      >>
                      >>
                      >> I think the MAIN reason why "clean" prominence is so widespread in
                      >> published lists
                      >> is because of historical precedent : it was only much later I demonstrated
                      >> that a
                      >> list based on interpolated prominence is more accurate, i.e., correctly
                      >> placing 75% of
                      >> "gray-zone" peaks as either "on" or "off" a given list of specified cutoff
                      >> value.
                      >>
                      >> I should post my PROOF of that claim at some point.... in the meantime
                      >> please
                      >> just have faith in it!!
                      >>
                      >> (Stated differently, there was INITIALLY no reason to discredit clean
                      >> prominence. Now there IS.)
                      >>
                      >> *************************************************************************
                      >>
                      >> I agree with Petter that it's disconcerting to compare two prominence
                      >> lists and find
                      >> that the ORDER differs of ranked peaks - and it's generally because map
                      >> contour intervals
                      >> are not identical for all summits and their key saddles (else there would
                      >> be an IDENTICAL
                      >> shift "up" or "down" of values for clean and interpolated tables - the
                      >> ORDERING being uneffected).
                      >>
                      >> I also think of my P600m count (actually, P2000 foot count) as the sum of
                      >> the clean count plus exactly one-half the gray-zone count. THAT way, in a
                      >> statistical sense
                      >> of long-term averaging, the final count should be closer to my unknowable
                      >> "true" count
                      >> than just using clean values.
                      >>
                      >> Adam Helman
                      >>
                      >>
                      >> ----- Original Message -----
                      >> From: Petter Bjorstad
                      >> To: prominence@yahoogroups.com
                      >> Sent: Tuesday, November 01, 2011 11:41 AM
                      >> Subject: Re: [prominence] Re: Prominence
                      >>
                      >> Hi Greg,
                      >>
                      >> Thanks for a very clear and concise reply.
                      >>
                      >> Let me first give you and Peakbagger a BIG hand for all the good work,
                      >> in particular, also recent updates that certainly shows that Peakbagger
                      >> follows important trends as technology facilitates more advances.
                      >> I keep an eye on pages like http://peakbook.org , it is a pretty "modern"
                      >> design with pictures, trip reports, lists, multi-language support etc..
                      >> It currently falls behind on the degree of coverage and having a much less
                      >> international user base. Again, your work is greatly appreciated!!
                      >>
                      >> The fact that you give lower/upper contours where spot elevations are
                      >> missing,
                      >> ie. of almost all key saddles, is also "WAY TO GO".
                      >> In fact, I find the information about prominences of peaks to be more
                      >> comprehensive
                      >> and reliable on Peakbagger than on any other Internet site.
                      >>
                      >> I discovered your clean prominence practice when I noted that the number
                      >> of peaks
                      >> climbed on some of my lists deviated from your lists. As there will be
                      >> multiple
                      >> lists around, I also obviously agree that it would have been "best" but
                      >> possibly not
                      >> so easily achieved, if lists used a consistent definition. There are TWO
                      >> issues,
                      >> the ORDER of the peaks in a list, and how to establish the correct CUTOFF.
                      >>
                      >> One may in fact argue, that the order is perhaps even more important than
                      >> the cut.
                      >> Now, as accuracy improves, the order that follows from an interpolated
                      >> based list is
                      >> going to be MORE correct (ie. in need for fewer interchanges), than a list
                      >> based
                      >> on "clean" prominence. For the majority of peaks this is not a question of
                      >> making the
                      >> list or not, but to establish the best possible (given the available data)
                      >> order.
                      >>
                      >> The cutoff zone of a list can always be arranged in such a way that one
                      >> sees which peaks
                      >> fall below the clean treshold, but remain on the list within the zone of
                      >> uncertainty.
                      >> When it the comes to stating say, how many P600 have you climbed? Then I
                      >> prefer to
                      >> report all P600 above the interpolated cutoff. Say I have climbed 300 P600
                      >> based on
                      >> clean, then an additional 10 within "optimistic" of which 4 are within
                      >> "interpolated".
                      >> I will then state that I have climbed 304 P600 peaks. This figure is
                      >> likely to be more
                      >> correct than either 300 or 310.
                      >>
                      >> Best regards,
                      >>
                      >> Petter
                      >>
                      >> ----------------------------------------------------------
                      >>
                      >> No virus found in this message.
                      >> Checked by AVG - www.avg.com
                      >> Version: 10.0.1411 / Virus Database: 2092/3989 - Release Date: 11/01/11
                      >>
                      >> [Non-text portions of this message have been removed]
                      >>
                      >>
                      >>
                      >
                      >
                      > [Non-text portions of this message have been removed]
                      >
                      >
                      >
                      > ------------------------------------
                      >
                      > Yahoo! Groups Links
                      >
                      >
                      >
                      >
                    • Roy Schweiker
                      ... Early on, the Washington state people favored clean prominence and drowned out other voices. Recently, interpolated seems to be winning. ... The AMC
                      Message 10 of 13 , Nov 1, 2011
                      • 0 Attachment
                        >Was there ever a poll in this e-group on this issue?
                        >Did one side or the other have a clear majority?

                        Early on, the Washington state people favored clean prominence and
                        drowned out other voices. Recently, interpolated seems to be winning.

                        > (Also--does anyone pefer optimistic ["dirty"] prominence?)

                        The AMC 4000-footer list could be said to use dirty prom, several peaks
                        would not belong under clean or interpolated

                        >>Some people prefer the most mathematically valid estimate,
                        >> which is fine, but others would prefer to tread cautiously
                        >>and err on the downside in terms of counts or list inclusion
                        >>(via dirty prom).

                        Note that if you choose to use clean prom on making a list to be sure
                        that only "guaranteed" peaks are on it, you should use dirty prom to
                        report finishing most types of lists to "guarantee" that you got
                        all/correct peaks. This sounds peculiar, but think of it this way - the
                        list of 4k prom shows only clean peaks but to be sure you got them all
                        you need to climb the dirty ones too. And as Adam can demonstrate, except
                        in cases of no overlap the list of 100 peaks with highest clean
                        prominence is unlikely to have the peaks with highest true prominence.

                        ____________________________________________________________
                        Penny Stock Jumping 3000%
                        Sign up to the #1 voted penny stock newsletter for free today!
                        http://thirdpartyoffers.juno.com/TGL3141/4eb09237165b77e1dbm01vuc
                      • Dennis Poulin
                        I m sorry that I am joining this discussionn so late, but I was busy. The P2k list in the US is nice and inclusive, but I have noticed that when a list is
                        Message 11 of 13 , Nov 10, 2011
                        • 0 Attachment
                          I'm sorry that I am joining this discussionn so late, but I was busy. The P2k list in the US is nice and inclusive, but I have noticed that when a list is completed, the first question is "did you do the error range peaks". If unofficially we don't recognize a list completion until the error range peaks are completed, then they should be included in the list. To complicate this issue further, we recognize P600 meter peaks in other countries as the equivalent of the P2k list in the US. My observation is that if you include the US P600 meter (1969ft) peaks with the P2k list, then you have included the error range peaks in the total peaks with a few exceptions. I also like to have lists with an absolute value. Hiking Club lists have no error range peaks included. If you hike all the peaks on the list, you have completed the list with no questions asked. I think we can develop a complete list of US P2k peaks by limiting our discussion to which error range peaks should be included. Of course the individual ranking of the peaks within the list may vary by the method used to evaluate the prominence. Then there is the issue as to which peaks are included in the P4k and P3k lists also.... Dennis Poulin
                          To: prominence@yahoogroups.com
                          From: ericjnoel@...
                          Date: Tue, 1 Nov 2011 13:09:39 -0700
                          Subject: Re: [prominence] Prominence




























                          Have you ever been asked to guess an adult's age? If so, you might have come up with a number and then guessed something a bit lower because guessing too high has a certain negative insulting implication to it that does not occur if you guess too low. That is to say, there are social/psychological aspects that make an outcome on one side of the "best estimate" less desirable than one on the other side.



                          To me, that is the aspect that Greg mentioned which seems to resonate with some folks but has no value to others. Some people prefer the most mathematically valid estimate, which is fine, but others would prefer to tread cautiously and err on the downside in terms of counts or list inclusion (via dirty prom).



                          Using Petter's handy example, let us suppose that his "true" P600m peak count is 303. Is it better to use a mean best guess estimate of 304 and overstate his count his by 1 or is it better to estimate just the 300 clean and undercount by 3? I'm sure that many would prefer the more accurate estimate of 304. In that position, I'd be partial to the 300 count myself because I would rather lose credit for something accomplished in those 3 error range peaks tagged than to take credit for something not accomplished in the 1 that isn't a P600 in this example. The latter outcome is preferable even if less accurate. People of a certain sensibility just have that preference to be conservative in their estimates. To each (webmaster) his own I guess. Ideally, I want my peak counts in clean prom and my list completion cutoffs in dirty prom with all peak rivalries included. That's just what Greg does currently and because of that approach users can be pretty confident

                          than neither peak counts nor list completions are overstated to confer a false positive as would happen much more often if one uses mean prom.



                          -Eric



                          --- On Tue, 11/1/11, Adam Helman <helman@...> wrote:



                          From: Adam Helman <helman@...>

                          Subject: [prominence] Prominence

                          To: prominence@yahoogroups.com

                          Date: Tuesday, November 1, 2011, 11:55 AM







                          I think the MAIN reason why "clean" prominence is so widespread in published lists



                          is because of historical precedent : it was only much later I demonstrated that a



                          list based on interpolated prominence is more accurate, i.e., correctly placing 75% of



                          "gray-zone" peaks as either "on" or "off" a given list of specified cutoff value.



                          I should post my PROOF of that claim at some point.... in the meantime please



                          just have faith in it!!



                          (Stated differently, there was INITIALLY no reason to discredit clean prominence. Now there IS.)



                          *************************************************************************



                          I agree with Petter that it's disconcerting to compare two prominence lists and find



                          that the ORDER differs of ranked peaks - and it's generally because map contour intervals



                          are not identical for all summits and their key saddles (else there would be an IDENTICAL



                          shift "up" or "down" of values for clean and interpolated tables - the ORDERING being uneffected).



                          I also think of my P600m count (actually, P2000 foot count) as the sum of



                          the clean count plus exactly one-half the gray-zone count. THAT way, in a statistical sense



                          of long-term averaging, the final count should be closer to my unknowable "true" count



                          than just using clean values.



                          Adam Helman



                          ----- Original Message -----



                          From: Petter Bjorstad



                          To: prominence@yahoogroups.com



                          Sent: Tuesday, November 01, 2011 11:41 AM



                          Subject: Re: [prominence] Re: Prominence



                          Hi Greg,



                          Thanks for a very clear and concise reply.



                          Let me first give you and Peakbagger a BIG hand for all the good work,



                          in particular, also recent updates that certainly shows that Peakbagger



                          follows important trends as technology facilitates more advances.



                          I keep an eye on pages like http://peakbook.org , it is a pretty "modern"



                          design with pictures, trip reports, lists, multi-language support etc..



                          It currently falls behind on the degree of coverage and having a much less



                          international user base. Again, your work is greatly appreciated!!



                          The fact that you give lower/upper contours where spot elevations are missing,



                          ie. of almost all key saddles, is also "WAY TO GO".



                          In fact, I find the information about prominences of peaks to be more comprehensive



                          and reliable on Peakbagger than on any other Internet site.



                          I discovered your clean prominence practice when I noted that the number of peaks



                          climbed on some of my lists deviated from your lists. As there will be multiple



                          lists around, I also obviously agree that it would have been "best" but possibly not



                          so easily achieved, if lists used a consistent definition. There are TWO issues,



                          the ORDER of the peaks in a list, and how to establish the correct CUTOFF.



                          One may in fact argue, that the order is perhaps even more important than the cut.



                          Now, as accuracy improves, the order that follows from an interpolated based list is



                          going to be MORE correct (ie. in need for fewer interchanges), than a list based



                          on "clean" prominence. For the majority of peaks this is not a question of making the



                          list or not, but to establish the best possible (given the available data) order.



                          The cutoff zone of a list can always be arranged in such a way that one sees which peaks



                          fall below the clean treshold, but remain on the list within the zone of uncertainty.



                          When it the comes to stating say, how many P600 have you climbed? Then I prefer to



                          report all P600 above the interpolated cutoff. Say I have climbed 300 P600 based on



                          clean, then an additional 10 within "optimistic" of which 4 are within "interpolated".



                          I will then state that I have climbed 304 P600 peaks. This figure is likely to be more



                          correct than either 300 or 310.



                          Best regards,



                          Petter



                          ----------------------------------------------------------



                          No virus found in this message.



                          Checked by AVG - www.avg.com



                          Version: 10.0.1411 / Virus Database: 2092/3989 - Release Date: 11/01/11



                          [Non-text portions of this message have been removed]



                          [Non-text portions of this message have been removed]


















                          [Non-text portions of this message have been removed]
                        Your message has been successfully submitted and would be delivered to recipients shortly.