A Real Life Off-by-One Error

I just did it and it didn't jump out for me at all. Odd

It works. It is actually my secret technique when solving "find five differences".

I don't understand how this works. If I cross my eyes, the images become extremely blurry. I can't even tell if they are precisely overlapping or not, let alone see if one of the holds is out of place.

Am I the only one?

I tried this, and while I didn't have any difficulty establishing a stereoscopic view it didn't jump out for me at all. I perceived the blue line floating on top of the problem handhold, but the handhold seemed to be on the same plane as all the others. Knowing it was the problem one, I could use the stereoscopic view to see it, but without already knowing I don't think it would be apparent.

This is odd to me since I've successfully used stereoscopy in the past to find small differences. For some reason, with this image, rather than causing a change in perceived z-level, my eyes fight for dominance and my left ends up winning.

Good idea. I just tried that on the first image of the whole route (after zooming in a bit) and the misplaced hold looks like it's floating in space away from the wall.

Not an off-by-one error—at least not in spirit. Interesting nonetheless.

Literally it was an off-by-one error. Literally, literal meaning.

Even if the out of place hold were used, would you then conclude it to be causal? I still wouldn't rule out coincidence. Many discoveries happen as a result of investigating spurious patterns.

Also the author rules out psychology, but I wouldn't, especially since there were multiple confirmed errors in the route preparation, which I expect could reduce one's trust in the fairness of the competition. In the moment, I might start to wonder, "If one hold was out of place, why not more? Is anyone even checking this?" even if untrue / unlikely.

It may not be a fencepost error, but I think it's still off by one.

People are misunderstanding the meaning of an off-by-one error. Suppose the plan states that hold A and hold B need to be 11 holes apart. In the true spirit of the off-by-one error, this can be interpreted in 3 ways:

- either as 11 empty holes between the holds; - as 11 holes, start counting 1 just above hold A; - or as 11 holes, start counting with hold A as number 1.

Another real-life example, is a plumber who tells the construction worker that the distance between the holes for hot and cold water needs to be 15 cm. This was meant to be measured center to center, but the constructor worker interpreted it as the distance from the right side of the first hole to the left side of the second. The result can still be admired in our house, 10 years later.

They run the whole 15 meter up in about 5-10 seconds (quite amazing to watch: https://m.youtube.com/watch?v=8O4g8JmWn9E ). At that speed, a small disturbance from the path they internalized means that they need to switch back to thinking which will take them out of their flow.

So it seems like the error discovered by the article author should not have conferred any advantage to the climber on the left.

They might not use the hold by physically touching it, but they might still use it as a visual indicator of where the other holds are in relation. These competitors are used to the same layout for many years. If there is a slight misrepresentation it can surely put them off.

The climbers had complained about an issue with the belay ropes on the right side that they also fixed.

A few of the climbers had said that the automatic belay ropes on the right hand lane did not feel right, so the cherry picker was replacing those and not the hold that I had noticed being out of place. The climbers had noticed something wasn’t quite right, but hadn’t said anything about the out of place hold.

It was probably just two separate problems.

The same wall config is only for the speed competition. There has been debate about changing it though, cause like you said they become muscle memory and hyper-optimized.

There are other forms of competition:

- bouldering: how many of 4 short boulder problems can you finish

- lead: how high can you get on a longer, higher route (pictured on the right of the image in the article)

In these ones the problems are switched up every competition.

I don't watch this event but, coming from other sports, I think there's more to this than sheer muscle memory. Humans are not machines. Sometimes you compete with ongoing or lingering injuries. Conditioning changes even for the most disciplined of athletes. All of these mean that a different approach might be warranted for each event depending on your "set-up".

Not to mention other variables outside of the human body. Perhaps the type of rope could matter in your performance. The age of the holds could matter too; even when the governing body standardizes on a replacement period for holds, I'm sure competitors would have strong opinions about the difference between a hold at the start of its service life versus one about to be replaced.

Also, the one thing I love seeing in physical contests is how competitors eke out the last bit of performance advantage with sheer willpower. Muscle memory takes care of the actions but performance and willpower is a conscious effort.

In short, no, I don't think competitors can literally turn off their conscious brain and just let muscle memory take over. If a field has jargon, there's a hell lot to geek over it.

Seems bizarre to keep the same wall config for all of time. The sport becomes about muscle memory more than anything else.

Plenty of other sport are pretty much the same each time, particularly track and field.

as a ... competitor

Are you?

Once an activity has become a “competitive sport” it has a way of prioritising “measurable” over meaningful or enjoyable. When you develop a critical eye for this aspect of sport, the Olympics stop being enjoyable and become an utter horror of human maladjustment, a horrid parody of what it alleges to stand for.

People use "real life" and "not in a computer" interchangeably

Unless we live in a simulation.

Some can be imaginary no? Or do you think everything is real life? In which case what’s the meaning of “real life”?

Real life v.s. IEEE-754 life

The number on your yearly "birthday" is not the number of birthdays you had (you only have one birthday) but the number of years you survived since your birth.

So the day of your fifth birthday is the first day of your sixth year alive.

Jewish law sometimes counts from 1 instead of 0 for birthdays, so a newborn is not 0 years old, they are in their 1st year. (But it's written as "when they are 1", so you have to know which counting method is being used.)

Korea has a system similar to this. You start at age 1 and get one year older each New Year's Day. https://www.90daykorean.com/korean-age-all-about-age-in-kore...

A few seconds in an image editor could do it too

Mistakes happen: https://apnews.com/article/ncaa-portland-3point-line-d78742b...

You wouldn't say "these instructions should be deleted because branch prediction and speculative execution in recent years have made it so that total cycle count is the same without them"

This is a very different statement than the original, and furthermore the original might actually trigger performance issues e.g. while the operation might not be used anymore it can have side effects (like triggering a prefetch) which end up affecting downstream code.

In the benchmark analogy, that piece would be a line of code that can be optimized away by the compiler. It could still matter if the code (course) is recompiled (rerouted) for a different architecture (climber).

My analogy is that "The bug is in the error-handling portion of the common fast-path speed traversal of the climb."

The fast path that the speed climbers commonly use doesn't involve the slower path involving the buggy portion.

But if the climber can't get up/further using the fast path then the climber may be forced to take the slower path.

Since the slower path is standardized, the climber knows how much effort/time is needed on the slower path.

Except on the righthand side, the climber's typical effort along the slower "buggy" path is different from the typical slower path and will result in an even slower time aka the execution time in the error-handling path is larger than usual...

"these instructions should be deleted because branch prediction and speculative execution in recent years have made it so that total cycle count is the same without them"

Then a new CPU architecture becomes popular, and spiders start winning every speed climbing event

The grips are placed on a grid. It was supposed to be at, say, (43,55) but actually placed at (42,55).

The fourth hold from the top in the right hand lane was off by one with respect to its counterpart in the left hand lane.

There's a misconception that a quadrennial sports festival. Actually, they're a quadrennial festival for people who never cared about the sport before to explain how it should be fixed.

How about a route pool like an esports map pool?

It would be terrible from an athlete perspective

You could also simply take two photos and overlay them. The difference would be obvious immediately to the human eye.

It is Crater Lake, from a second visit this summer.

This is indeed what is argued in the article.

Sometimes climber, but not a speed climber: it would be vanishingly unlikely for a hold that far left of the button to end up on a more efficient route. Closer to the middle of the route, maybe, but it'd be a sharp jog to the right to hit the button from having any appendage on that hold.

I had a similar experience in getting a Math BS after finishing an Econ BA (which, for my school, was notoriously short and was not seen as sufficient to prepare you for economics graduate work).

The deal with my Math dept head was I had to make it my primary major (no true doubles at my weird undergrad, had to have an "additional"). It was a deal I was happy to make if it meant skipping an intro-to-proofs course after having taken the masters level series in most the of the fields they offered!

If you're curious about those, they're all photos of the various sporting events that happen in the village here. All the effects you see are captured in camera through movements or otherwise.

Where was the off by one error? I read the article and didn't find any mention of it.

When the Japanese delegation protested – could they accept a botched surrender document?

For some reason I find this a bit humorous. My dudes, you do not have much leverage.