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Moof
Trad climber
A cube at my soul sucking job in Oregon
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"YUR GUNA DIE!!!"
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Chiloe
Trad climber
Lee, NH
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Because it is easier to do so, I will violate some statistical principles here.
And in that same spirit ...
IF there is, randomly, 1 chance in 100 that something will fail, or a probablity of .99 on any given trial that it won't,
THEN the probability of two trials (two falls, climbs, space shuttle launches or whatever) without failure is just .99 x .99 = .98 or 98%, which might still sound high.
BUT it gets worse if you look farther ahead. Although the probability of no failure on any one climb would (in this fake example) remain the same, .99, the probability of making 100 climbs with no failure is .99 to the 100th power, only 37%. And for 1,000 trials, the likelihood of no failure gets closer to zero.
On your 1,000th climb, if you've had no failures so far and failures are a random event, the probability should (contrary to a superstition called "the law of averages") be same as it ever was, 99% for success. But looked at over a career, the theoretical odds against random failure aren't so good.
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happiegrrrl
Trad climber
New York, NY
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I think this is an excellent candidate for a Supertopic/ArseeDotCom Blind Taste Test. Simply post the same original post over there and compare results.
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GOclimb
Trad climber
Boston, MA
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Happiegirl, I agree, that'd be fun!
Everything is situational.
I've belayed off this:
and I've belayed off this:
I've also belayed where the only anchor was my fat ass wedged in a crevasse, and I guarantee, it wasn't going anywhere!
Here's one I didn't want to belay off!
GO
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Nick
climber
portland, Oregon
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Can a Gnome troll? I don't think all of your lobes are functioning. Go back to your search for the wood fairies. Damn you and your fair weather too. I once belayed off a knotted runner jammed in a crack, bomber. No worries, gnomes don't fall they roll.
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Matt
Trad climber
places you shouldn't talk about in polite company
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G-Gnome-
I once had a partner get a little uneasy when I took a couple of small cams from him, upon his arival at the belay after following a pitch, and I added them to the anchor before I took him off belay. He asked me what I'd just belayed him on and I kinda smirked while I told him it was a slammer yellow alien, sunk several inches into a perfect placement- not goin anywhere.
The truth was that I was wedged in behind a sort of flaring corner and had a kneebar that would have made it really easy to hold him if he'd fallen, based on the angle of the feature and the direction of pull he'd have given me. I would have never had to weight the piece if he'd fallen, I'd only have been more wedged in there. Still, the process of deciding I was OK w/ that was a pretty interesting moment in my climbing career. I really believe the abundance of modern gear makes us all have to be far less creative and far less bold.
Better climbers have belayed with less, it's all situational, and I felt good enough about my anchor to trust our lives to it, but I would have happily taken something more if was available. Like I said, my partner was a little bit uneasy, but I think that was just because we were 10 or 11 pitches up on the DNB, and folks have been known to rip off that rig...
=/
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Mighty Hiker
Social climber
Vancouver, B.C.
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Perhaps some stannardtistical methods should be applied to the problem? As has been said of politics, there are lies, damned lies, and stannardtistics.
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Ksolem
Trad climber
LA, Ca
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G Gnome, would that be the red Camalot you borrowed from me..?
Perhaps I should have told you where that thing has been. Oh well. What you didn't know didn't hurt you..
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G_Gnome
Boulder climber
Sick Midget Land
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Topic Author's Reply - Feb 6, 2007 - 07:30pm PT
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Nah Kris, I used yours to hold the rope where I knew I wouldn't fall while leading. Do you honestly think I would trust any of your gear?
And for the record, I have belayed by sitting down on a ledge and putting my heels on a bump and wrapping the rope around my waist. Many times! I also held a factor 1.5 fall off a single size 7 stopper. That's when I learned to protect against the idiot factor cause that person never should have fallen there.
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jstan
climber
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I have been properly chastised and much appreciate it. Now I don't have a good calculation with confidence limits for two reasons:
1. My computer is making mistakes!
2. I am too lazy to take G Gnome's calculation to 200 lives and then do it many times. I did it for 70 lives, 100 lives and 200 lives. I did look at other per event rates. You die a lot if you get very far from one in a million.
If you assume random statistics, a per event failure rate of 1e-6, a thirty year life in each day of which there are two events in which the anchor must not fail, G Gnome has a chance of not cratering in thirty years somewhere between 95% and I would guess 98%. That using his one in a million value for a single event.
You can't make statistics sound decisive which is why Werner's "when your number is up" feels so uncomfortably close to the truth. I created Stannardistics(Anders, I will get even for this come the next Facelift.) in hopes of making it sound worthwhile always to back yourself up. To live a long life your per event failure rate has to be way below anything you could measure or sense. Never pass up a chance to stack your factors.
If you can sit to belay, you are crazy to pass up the chance.
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keep looking up
Trad climber
ocean west
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while observing from another location in JT Saturday afternon;
I reminded a newbie, "safety first" when he, 180 lb)was going to rappel from a single nut...to the ground;
he could easily walked off the route in minutes....he reconsidered and then beefed up the anchor....
just doing a good deed for the day
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Gnat
climber
Smell A
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It is pure folly to try to apply statistics to the unique circumstances of climbers and climbing anchors. The variables are too great to simplify. And in simplifying them, the resulting assumptions are highly like to so far off as to be completely wrong (as will the conclusions).
It is all situational.
Nice stir of the pot G-gnome.
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Mighty Hiker
Social climber
Vancouver, B.C.
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John: Agreed. A sitting belay is almost always stronger and more stable than standing, and is sometimes sufficient unto itself. (The Squamish variant is to wrap your legs around and sit above a tree.) But it's always worth having a backup. And if there's any chance at all of relying on the anchors, two or three are better than one.
That said, sometimes there isn't much choice.
My apologies for the dreadful pun.
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Tarbuster
climber
right here, right now
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G Gnome wrote:
"I was hip belaying in the gym the other night and they made me leave. Cowards. Just because they never learned good skills is no reason to penalize those of us who did.
And of course I was drunk."
Hmmm...somethings missing in this reportage Jan...were you also nekkid? 'Cuz I could see them tossing you out of the joint for hip belaying, while drunk and nekkid. That's right, go on Gnomer, come clean on this one for us; you'll feel better.
End thread drift, back to snappy stats and such.
You heard it here.
-Tarbaby.
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jstan
climber
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Getting long winded but if Rgold is right (always a good assumption) there is something really important here.
If people are being taught there is a standard way of doing things and if you do it that way you have nothing to fear, a lot of damage is being done. Here Gnat's post hits the mark. Liability considerations in the commercial instruction environment impel a policy decision that there be only one output from the instruction. There is only one approach approved(by the insurance company). This has no @ relationship to the real world. Are we being shoehorned into serious and painful errors simply because it benefits some one financially? I will leave it at that.
Chiloe also hit the mark. If you plan on doing something a lot - you better be doing it very very well.
And no Anders. People who pick up trash together don't need to apologize. Besides, you were right.
Cheers,
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k-man
Gym climber
SCruz
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I could have been pulled off except for the size of the feet I was standing on.
OK I'll bite. How big are your feet?
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Crimpergirl
Social climber
St. Looney
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And whose feet were you standing on?
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Anastasia
Trad climber
Mammoth Lakes, CA
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Only a cam? How sad, there is no fun without a proper pair of nuts.
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justthemaid
climber
Los Angeles
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I recommend you bring up a canary in a cage next time. I f the canary keels over dead the cam placement is clearly unsafe.
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