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Re: Road Types (USA) – comprehensive overhaul of drivable ro

Sun Mar 30, 2014 1:17 am

Indeed, separate issues, but related.

While the pruning thing seems like a bug, it could in fact be a larger form of the preferring that occurs in shorter trips, and that 'preferring' gets so strong and so oversimplified on long trips that it turns into 'pruning.'

You yourself gave an example that I forget the details of, but in New Orleans, you were like 'this route was never considered until I turned such and such a road into a major highway.' It was a short distance trip. The fact that it was 'never considered' suggests 'pruning' to me.

I really do think it's 'pruning' non-major highway options even on short trips, too, is my point. The ONLY time it even uses non-major highway options is IF there is traffic on the major highways to avoid. Otherwise it doesn't just 'prefer' them, it sticks to them like glue and 'prunes' other options out of the picture, even options that would possibly be faster. And especially in areas with lots of major highways (thanks to sketch's standard which has them scattered all over the place, sometimes every 200 feet), the more impossible it becomes to get suggested a route that doesn't focus on them like moths to a flame.

This is just a suspicion, I can't prove it (except for 'detour avoidance' which is actually designed to ignore the faster route if it qualifies as a 'detour').

But I keep going back to how sketch said "I never had that route suggested until I made it a major highway." When I hear that, I don't hear "let's have more major highways so there's more routes" (which may in fact be true and is certainly sketch's approach to the problem), what I hear is "the only routes it ever gives are major highways." Which makes me wish they could be used more scarcely (for 'other freeway/expressway' and not for primary arterials). Which they could, if not for the long-distance bug that seems to require them. This is why I link the 'pruning' and 'preferring' as basically two sides of the same issue.

You keep saying my experience must be different. So let's focus on my experience, then. I use Waze on the route to work every morning, and on the way home every evening. (And everywhere else I go, but that's the most common, repeated trip.) This is the livemap link from home to work:

https://www.waze.com/livemap?zoom=16&la ... =-82.40321

The only two routes I ever get are taking North Church all the way to (near) University Ridge and come in from the east side, or taking N Church to Academy and then getting off Academy at Camperdown and coming in from the west side.

That's it. That's the only routes I ever get offered. Either going or coming. Ever. Once, one time only, I was offered the Interstate instead, then to N Church.

Now, granted, I haven't experimented all that much about going off 'the beaten path' and trying to find shortcuts. After all, that's what I supposedly have Waze for, to tell me about them so I don't have to find them myself, if/when they are faster. But generally speaking, especially going in to work, N Church street tends to have a good amount of traffic, especially between E Park and E McGee. But the only way it ever routes me around that traffic....is to take a different major highway. =/ Not once has it ever offered me any other solution to avoid that N Church St traffic; it's always to take Academy instead. Never anything else. Ever. Ever ever ever ever ever ever ever ever.

Granted I've only been working there since the week before Christmas, but in all that time, taking this commute 10 times a week, you'd think I might have gotten more than just those 3 variations of the trip (one of which was only once). =/ Not to mention that accident that occurred on Wade Hampton one time and added 20 minutes to the commute home because Waze didn't realize that my doing 2MPH average might mean I should get routed around the traffic jam. =/ (I wound up getting UR's from someone who had obviously gotten routed around the traffic jam after it had already cleared up and they were wondering why Waze was telling them to get off Wade Hampton. -eyeroll-)

I would challenge anyone to find a time of day where this commute does not stick like glue to either N Church (a major highway) or Academy (a major highway.) =/ Because I've yet to find one, regardless of what traffic's like. Essentially traffic has to come to next to a standstill in order for the penalty to be severe enough for it to start looking at the minors/primaries in the area. And since that doesn't happen without an accident or something like it, it pretty much always follows the "better to use these roads than the backroads" philosophy, pretty much permanently.

So that's my experience. The only main reason I can think of why my experience is so much different is because there isn't a strong amount of Wazers in this area. Which makes me wonder why a standard that doesn't fit for areas of low usage would be a good standard to apply nation-wide. =/

Re: Road Types (USA) – comprehensive overhaul of drivable ro

Sun Mar 30, 2014 1:51 am

bgodette wrote:
Thortok2000 wrote:But my point is made: 99% of the time, it's going to stick to the major highways like glue, and only if there is a SEVERE (subjective term) amount of traffic on the major highways will it consider other options.

Basically, if a non-major highway is the faster route with ZERO traffic on both that route or the major highway, it will STILL choose the major highway....because it's a major highway. It's only if the major highway is actually experiencing traffic that it doesn't use the major highway.
Except that's not the experience here, for routes that are quicker using non-MH/Freeway it will happily give them to you. Those instances are few and far between simply because anything that's used for serious connectivity is generally already NFC'd as an arterial or expy or interstate.

As I said in an earlier post, this is less of a problem when the road is a major highway because it's a primary arterial and it actually DOES get/deserve that amount of traffic. The bigger problem is typing it as a primary arterial when it isn't. Or in other words, typing it as a major highway just because it's got a US number.

The point I made to sketch in the other thread is that the DOT or whoever does the numbered highways looked at the map and filled in holes where roads needed to be, and the people that do the functional specification maps looked at how much traffic the roads do and/or can actually take. Obviously the people doing the functional specification know it's a US highway, if they say it doesn't actually warrant being a primary arterial, then I'd assume they have a reason for it. Giving it primary arterial treatment in Waze anyway is the problem.

And as I said before, if it's required to fix the long distance routing bug, so be it. But it's to fix a bug, not because a hybrid FC system is better than a pure FC system for any other reason.

So, going back to THIS point, yes, the times where a non-primary arterial road would actually be a faster trip than a road marked as a primary arterial are pretty few and far between, because the FC did a pretty good job of labeling the roads correctly. So the issue of "but this road over here is faster, and I got stuck on the major highway anyway" specifically applies only in cases where that road is a major highway ONLY because it's a US highway, and the FC has labeled it as not a primary arterial. Which isn't all the time, but isn't that rare either.

bgodette wrote:
Thortok2000 wrote:Experience says otherwise. In fact, so does the wiki! The entire reason we set at-grade connectors to have the same type as the roads they're connecting is because of penalties in changing type. Same with the instructions on what type to use for roundabouts depending on what roads they connect. If there wasn't a routing penalty for changing types, we wouldn't have to do that, would we?

The wiki is wrong if it says that. There are no penalties for changing type except for Private/PLot to anything else. Most of the type rules for connectors and roundabouts are mostly about aesthetics and not anything to do with how routing works, and most of them were written before anyone knew anything about the actual data model being used. Most of what we know now is only known because some editors developed ways to actually test the assumptions we thought were true or believed because someone heard from someone else who heard from yet another person who interpreted what was said in passing in an email and it's gone through 4-5 language translations.

Why do so many of the discussions on here turn into "The wiki says this" with a response of "The wiki is wrong"?

The only way I have to prove anything is anecdotal experience and wiki. If the wiki is wrong, then fix it...that's why it's a wiki, so people can fix it and keep it up to date. Why I get 'the wiki is wrong' so much, I don't know. >.<

In any event, here's at grade connectors: https://wiki.waze.com/wiki/At_grade_connector#Road_type

And roundabouts, which goes into much detail about the routing penalty: https://wiki.waze.com/wiki/Roundabout#Road_type

Re: Road Types (USA) – comprehensive overhaul of drivable ro

Sun Mar 30, 2014 7:34 am

sketch wrote:What you're telling me is that upgrading the roads to meet this standard actually fixed the routing.

Yes, Waze could "fix" the routing system by allowing long routes over minor highways. (Fat chance.) Or, we could fix the Waze map to provide Major Highways for long routes, which is what we're trying to do.

This directly relates to what I said earlier: Upgrading the roads to fix routing is not what I hear, I hear 'it won't give it as a route unless it's a major highway.'

So, basically, the pruning problem that I consider a bug.

As far as the examples given in my area, I'd have to double check but the only spot I know of that is not based off of FC is Academy between College and N Church. That spot is labeled major only because it is a US highway. There's a few others around but for the most part the FC matches the numbered highway system fairly well. Interestingly enough, though, that section makes up one of the two standard routes I'm given on my commute. =P I often wonder what routing would do if that section was correctly labeled as minor, per the FC.

And perhaps I'm not being clear but routing on (or not on) major highways when they match the FC standard really isn't a problem. It's specifically when it gives preference to major highways that are US highways classified below primary arterial in the FC, it's giving preference to a road that doesn't support as much traffic and you're more likely to be able to find a faster way that doesn't include that major highway.

In the case of lack of data, though, it's going to prefer that major highway much more than it would if it was a minor highway instead. Minor highways and below are more often included in low-data areas when major highways are not present, I guess is the point I've been trying to make. When the major is a major because it's a primary arterial, that's not a problem as it's probably faster than the back roads. When it's a major because it's a US route, AND there's a lack of data for the back roads, then it's going to incorrectly prefer the US route, rather than consider back roads. Does that make sense? =P

Also, I never check the 'alternate routes'. Why would I? I want the fastest. Usually cause I'm running late to work or eager to get home, lol.

And in all the time I've been using Waze since I started in October, only ONCE has it actually changed the route after I already started driving (not counting when I drive off the route and recalculate of course.) Granted my drives are usually no longer than 40 minutes to an hour, and most are in the 20 minute and under range.

I was so surprised that I missed the new turn and it stuck me back on the original route anyway before I could even see where it was trying to lead me. =P

In any event, I think the preference to major highways is mostly coincidental correlation. Because of the lack of data around here, especially for side roads, the major roads get like 99% of the routing, and are simply calculated as faster. It generally IS faster to take the main road, I suppose.

My main problem probably lies with the fact that there's not enough Waze data to detect traffic sooner/faster and actually cause detours and rerouting. This is why I get stuck in traffic on major highways rather than avoiding it on back roads. Just like with that accident on Wade Hampton once, I was pretty much the Wazer that reported that data by sitting in the traffic jam, just in time for it to clear up so the Wazer behind me reported UR's for 'unexplained' detours off Wade Hampton and back on again, avoiding traffic that was no longer there. That's the kind of thing we put up with around here because there isn't as much data. =(
Last edited by Thortok2000 on Sun Mar 30, 2014 7:39 am, edited 1 time in total.

Re: Road Types (USA) – comprehensive overhaul of drivable ro

Sun Mar 30, 2014 7:42 am

I'm all for fixing it now, I just grimace at the method. It's like repaving the entire hundred mile highway to fix a handful of potholes.

If it was hybrid only where it had to be in order to fix bugs, and pure FC everywhere else, I'd be much happier. =P But I agree that's overly complicated, which is why I just sit and wish the bug would get fixed. =/

Re: Road Types (USA) – comprehensive overhaul of drivable ro

Sun Mar 30, 2014 7:57 am

A pure FC system would improve routing just as much as a hybrid system (better, in fact), if it weren't for the pruning problem.

That's really everything I've been trying to say wrapped up into one sentence. =P

If it's not clear, I've got nothing against your standard, I already agreed it was best back in that other thread. I'm just moaning and complaining that the standard is necessary over a pure-FC based one like Andy's because of less than optimal routing patterns and conditions that are beyond our control as editors. =/ I also wish there was an additional road type so that the FC could be mapped exactly instead of 'converted.'

Re: Road Types (USA) – comprehensive overhaul of drivable ro

Sun Mar 30, 2014 4:29 pm

Here's the key sentences on the roundabout page, you seem to have missed it (that's understandable, it's only the 2nd and 3rd sentences of the section):

To minimize inefficient routing, it is important to be careful with the road type assigned to the Roundabout itself. Any routing penalty going from connected roads to the roundabout must be kept to a minimum, but it should not be too "attractive" where routing through it is encouraged when unnecessary.

If these sentences are incorrect, they should be edited. They basically imply what I have been saying: Higher class roads are 'attractive' to the routing and it will go out of its way to use them, whereas changing from a higher type to a lower type receives a 'penalty' and is avoided except in cases where traffic on the higher type overcomes that penalty.

Re: Road Types (USA) – comprehensive overhaul of drivable ro

Sun Mar 30, 2014 4:38 pm

It would be nice if some testing was done on the minimum distance before pruning occurs. Because I really do feel like it does actually occur on shorter distance trips; maybe not every time, but fairly often. I just keep going back to your statement of that route in New Orleans that was never suggested until you made it a major highway. It was pruned. And it was a short distance trip.

Re: Road Types (USA) – comprehensive overhaul of drivable ro

Sun Mar 30, 2014 5:09 pm

How can I get in on being a routing test user?

Re: Road Types (USA) – comprehensive overhaul of drivable ro

Fri Jul 08, 2016 12:31 am

In the Highways section, what do folks think about adding a paragraph something like this:

In urban areas, "Highway" designations may be used to provide additional levels of granularity for road sizing. This depends on the state or city's categorization of the roads, using the terminology described in the sections below.

I suggest this because I was surprised to see roads in Boston labeled as "highways", and the current text repeatedly uses language referring to long-distance highways, which is a use not actually relevant here, but when looking at the MA GIS information, the classification is correct, they define roads within the city as principal and minor arterials, matching up with the designations. I'm open to other ideas/suggestions as well but think I can't be the only one who has been confused by this and could use a little clarification.


Re: Road Types (USA) – comprehensive overhaul of drivable ro

Fri Jul 08, 2016 11:21 pm

Thanks sketch. My problem with the section you quote is that it just isn't enough. No one in Boston would call Newbury St a highway, but that's what we (correctly, according to these standards) call it. It doesn't meet any part of the described "dictionary definition" of a highway either. This is the case with a ton of roads in Boston, which is what brought this up for me.
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