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Rocketman
02-10-2011, 12:33
A recent press release from Ohio State University.

http://researchnews.osu.edu/archive/seeslope.htm

A shortcoming that I see is that whenever I ask somebody coming towards me how steep is the trail ahead, they nearly always describe the uphills that I will face as "easy" and the "downhills" as hard. In practice, the "easy" stuff is almost always hard, and the "hard' stuff is easy. These authors don't even discuss this important factor of real trail experience.

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LOOKING AT A TOUGH HILL TO CLIMB? DEPENDS ON YOUR POINT OF VIEW

COLUMBUS, Ohio -- People tend to overestimate the steepness of slopes – and psychologists studying the phenomenon have made a discovery that refutes common ideas about how we perceive inclines in general.
For more than a decade, researchers thought that our judgment was biased by our fatigue or fear of falling, explained Dennis Shaffer (http://psych.mansfield.ohio-state.edu/shaffer.html), associate professor of psychology (http://psych.mansfield.ohio-state.edu/index.html) at Ohio State University’s Mansfield campus (http://mansfield.osu.edu/). We perceive climbing or descending hills as difficult or dangerous, so when we look at an incline, our view is clouded by the expected physical exertion or danger of traversing it.
http://researchnews.osu.edu/archive/dennisshaffer.jpg Dennis Shaffer For a study in the current issue (http://pss.sagepub.com/content/22/2) of the journal Psychological Science (http://pss.sagepub.com/), Shaffer and then-undergraduate student Mariagrace Flint uncovered a contradiction, when they compared how we perceive the angle of stairs versus escalators.
“We found that people tend to overestimate a slant even when they are looking at an escalator, and climbing or descending it would require practically no effort at all,” Shaffer said.
For the study, 200 passersby were asked to judge the angle of a set of stairs on the Mansfield campus, while another 200 were asked to judge the angle of an escalator in a Mansfield Sears store. In each case, 100 people viewed the angle from the top, and 100 from the bottom.

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The study adds to a growing body of evidence that body-based factors, such as climbing effort or perceived danger, do not have the strong influences on our perception of slant that researchers once thought.


On average, people consistently overestimated the slant by 18-19 degrees, regardless of whether they were looking at a set of stairs or an escalator, from the top or from the bottom. The actual slope of the steps was 25 degrees, and the slope of the escalator was 30 degrees, but people judged them to be an average of 44 degrees and 48 degrees, respectively.
“In fact, their overestimates were virtually identical,” Shaffer said.
The study adds to a growing body of evidence that body-based factors, such as climbing effort or perceived danger, do not have the strong influences on our perception of slant that researchers once thought.
At least, Shaffer added, we can take comfort that our misperceptions are consistent.
“The range of effort required for different activities – walking or running, riding a bike or a ski lift, driving or riding in a car, or riding an escalator – is large, and it depends on whether we’re feeling energized or fatigued,” he said.
“The constancy of slant perception shown here, like other perceptual constancies such as size, color, lightness, and orientation, guarantees that our perception of important features in the real world remains stable across large variations in viewing conditions.”
He suspects that our perception of slant is biased by a more basic misperception: the angle of our gaze. People, he says, tend to think they are looking downward at a sharper angle than they actually are.
“If people believe they are looking more downward towards the bottom of the hill, and the hill looks perpendicular to their line of sight from there, the hill could look steeper to them,” he said. “But this hasn’t been tested – we’re working on that next.”
Other research has already shown that people standing above a hill think the hill is less steep when they stand right at the edge, then more steep when they move back.
Shaffer is also studying a related effect: why, when viewing a hill from below, we overestimate slant more as we stand farther away – up to a distance of 50 meters, when our estimates level off.
Despite the apparent constancy of our misperceptions, Shaffer maintains that it’s possible for people to learn to judge slopes more accurately.
“I’ve had roofers take my class before, and they always seem to be accurate with their estimations,” he said.


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wornoutboots
02-10-2011, 12:45
I Never believe anything a passing hikers say's when it comes to distance, timing or trail toughness, it always proves to be different to me than what was predcited?? : )

TheChop
02-10-2011, 13:06
Estimating Trail Steepness?

Big ups?

Crap your pants.

Depends.

Odd Man Out
02-10-2011, 13:15
I don't think I needed a scientific study to know this. Ever drive down a road with a 10% incline? It looks like you are driving off a cliff. Now draw a 10% slope on a sheet of paper. It looks like no slope at all.

Pedaling Fool
02-10-2011, 13:16
I thought this was cool since I always wondered why they didn't measure inclines in simple degrees vice %'s. http://www.1728.com/gradient.htm

I thought this was interesting: "He suspects that our perception of slant is biased by a more basic misperception: the angle of our gaze. People, he says, tend to think they are looking downward at a sharper angle than they actually are.

“If people believe they are looking more downward towards the bottom of the hill, and the hill looks perpendicular to their line of sight from there, the hill could look steeper to them,” he said. “But this hasn’t been tested – we’re working on that next.”

It reminds me of cycling through Skyline Drive and the Blueridge Parkway. There are sections in which your eyes are telling you that you're going down hill, but you legs are telling you that you're going up hill.


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Majortrauma
02-10-2011, 13:39
This is one of most accurate and practical quotes EVER on this site...at least in my opinion.

I Never believe anything a passing hikers say's when it comes to distance, timing or trail toughness, it always proves to be different to me than what was predcited?? : )

On some of my section hikes I was wholly convinced upon finally reaching the destination that the hikers who just gave me "the scoop" were deliberately screwing with me and my kids. Now as a rule I don't ask people that question and especially in the presence of my kids.

sherrill
02-10-2011, 13:50
I stopped asking anything about the trail ahead when I came to the realization that there was nothing to be gained from it, at least for me. Doesn't change anything. You still have to hike it.

10-K
02-10-2011, 14:05
It's really simple.. No matter which way I'm going it's uphill.

Unless I go the wrong way, then it's downhill so when I figure it out I have to walk uphill to get back on track.

fredmugs
02-10-2011, 14:38
I Never believe anything a passing hikers say's when it comes to distance, timing or trail toughness, it always proves to be different to me than what was predcited?? : )

Especially if you're in NH. Last year in the Whites whenever someone gave us some trail intel we started asking where they were from. If it was NH we disregarded everything they said.

Pedaling Fool
02-10-2011, 14:45
If you're new to hiking never ask a thru-hiker how steep the upcoming trail is. One example of when an inexperienced person should never ask an experienced person for advice.:D

Cookerhiker
02-10-2011, 15:46
I agree, I would never ask a passing hiker what the stretch ahead was like, easy or hard, up or down, footing, etc.

I'd ask Lone Wolf.

Sickmont
02-10-2011, 15:48
I look forward to the challenge, so no, i'd never inquire either. However, if someone going the other way told me about a boatload of rattlers up the trail that, i think, would have to be considered. Just a little bit anyways.

Tenderheart
02-10-2011, 15:55
When I moved to my present address about six years ago, I laid out a six-mile-loop running route. As I ran the route daily for a few weeks, it became apparent that I was always going uphill, even though I arrived back at the same location, the end of my driveway. One day, I decided to run it backwards. The perceived flat sections were actually long sloping downhills, which I had not realized. Go figure!! And never ask an oncoming hiker for advice. He will lie, lie, lie.

litefoot 2000

Cookerhiker
02-10-2011, 15:59
When I lived in Western Maryland, I frequently cycled on the Great Allegheny Passage (http://www.atatrail.org) from Frostburg to the Big Savage Tunnel. The 6 miles to the tunnel ascended about 500' elevation - virtually nothing for a hiker/walker. But cycling, I definitely felt it! Good workout. And the ride back was the reward.

hikerboy57
02-10-2011, 16:00
I met a guy at the base of Mt Garfield with altimeter, reminding me evry 3 steps how much more we had to climb until I wanted to kill him. I prefer to walk until I'm done.Its a good idea to have some idea of the terrain you'll be tackling, so you plan the right amount of time(especially NH and ME.)But I prefer to simply hike/climb until I'm done. I find when I focus on "how much more?" i stop enjoying myself

4Bears
02-10-2011, 16:28
Whenever I'm hiking, I just figure if I am not going uphill, I soon will.

4shot
02-10-2011, 18:05
I stopped asking anything about the trail ahead when I came to the realization that there was nothing to be gained from it, at least for me. Doesn't change anything. You still have to hike it.

the evening and morning discussion centered on the upcoming day's hike. Every one studied and fretted over the guide book and the elevation profile and the name of every hill was mentioned. We were like football players reviewing the game plan. As time went on, those discussions stopped...as you said, whatever lay in front of you had to be walked and it made the hiking more pleasant (for me anyways).

Graywolf
02-10-2011, 18:59
I heard the best (and probably the most accurate) bit of hiker info. Upon leaving Three-Forks toward Hawk Mountain I found a GA AT hiking club out for some maintanence. Just to stoke up conversation, I asked, "How far to the next shelter?", (I had maps, I knew, just wanted to visit). The reply, "Oh, up the hill and to the left". "Ok, sir, thanks.."...And true to his words were.,

Up the hill and to the left.. I will never forget that.

Lemni Skate
02-10-2011, 19:42
As a math teacher this is not news to me. I've always known that we feel like a slope is much greater than it is when we're actually "a part of it."

I've always thought it was an odd phenomenon. Like someone said above. A slope on which we are burning out our brakes in a car is actually not much at all.

fiddlehead
02-10-2011, 19:56
My general rule of thumb is: 1,000 feet of elevation gain or loss per mile is a bit tough.
Anything less is fairly easy, anything steeper is something that I should pace myself for.
The steepest I ever saw was 3,000 feet per mile on a downhill in the Pyrenees.
The AT, probably the climb going up Lafayette.