Re: [OSM-talk] Why quality is more important than routing speed
I don't share your pessimism. I've mapped maxspeed=* quite a bit. Compared to name=*, it's no harder to map, and it is of increasing importance. I think we'll get far more than 8% of road names tagged in the long-term future, and I think the same of maxspeed=*. Well ... maybe not - since at least in my country, most roads have no speed limits posted on them (so basically, the national default limits, like max. 50 in city, etc ... apply) Having 8% of roads tagged with speed limits may be the most you'll ever have for some areas (cities tend to have more speed limit signs on the roads, many country roads have none ...) Martin ___ talk mailing list talk@openstreetmap.org http://lists.openstreetmap.org/listinfo/talk
Re: [OSM-talk] Why quality is more important than routing speed
I wasn't whining, nor was I suggesting that the project has no potential. In fact, I think there are lots of good answers to the question how do you use speed limit tags when only 8% of the roads are tagged with them? But I don't think think longer-term is one of them. On Mon, Jul 5, 2010 at 5:24 AM, Lambertus o...@na1400.info wrote: Did it prevent me from mapping when I discovered back in 2007 that the map was almost blank? Did I think that the project had no potential, could not become anywhere near suitable for routing? No, on the contrary. And look at where we're now, only three years later! Reasoning in half empty instead of half full won't lead us anywhere. Stop whining, be constructive. 2007On 2010-07-05 01:44, Anthony wrote: On Sun, Jul 4, 2010 at 6:33 PM, Roy Wallace waldo000...@gmail.com mailto:waldo000...@gmail.com wrote: On Sun, Jul 4, 2010 at 10:34 PM, Anthony o...@inbox.org mailto:o...@inbox.org wrote: How do you use speed limit tags when only 5% of the roads are tagged with them? Think longer-term. Okay. How do you use speed limit tags when only 8% of the roads are tagged with them? ___ talk mailing list talk@openstreetmap.org http://lists.openstreetmap.org/listinfo/talk ___ talk mailing list talk@openstreetmap.org http://lists.openstreetmap.org/listinfo/talk ___ talk mailing list talk@openstreetmap.org http://lists.openstreetmap.org/listinfo/talk
Re: [OSM-talk] Why quality is more important than routing speed
On Mon, Jul 5, 2010 at 6:13 AM, M∡rtin Koppenhoefer dieterdre...@gmail.comwrote: 2010/7/5 Anthony o...@inbox.org: Okay. How do you use speed limit tags when only 8% of the roads are tagged with them? Actually it doesn't matter at all, how many percents of the planet are tagged with a certain tag, it is sufficient that the tags are present in the area you are interested in ;-). Quite true. But to use an anecdote, I've recently returned from road trip where I was relying heavily on Android's navigation software, and I've found that Google tends to greatly overestimate the actual speed of the less traveled roads I decided to travel on. I'm not sure if it's because they don't have the speed limits for these roads at all and are using an overly high estimate, because they're not adequately factoring in traffic lights, or something else. I'd say this is a great opportunity for OSM, actually. The ability for me to easily correct silly routes (and get instant gratification on those corrections) is something I'm looking forward to. ___ talk mailing list talk@openstreetmap.org http://lists.openstreetmap.org/listinfo/talk
Re: [OSM-talk] Why quality is more important than routing speed
On Mon, 2010-07-05 at 00:42 +, John F. Eldredge wrote: However, you can't be certain, without personally checking the street in question, whether the street really has no speed limit signs, or whether the person who added the street to the map simply failed to add the speed limit tag. This could be said about any tagging. A road might be one-way but the mapper might have forgotten to add the oneway tag, or it might be bus only or only accessable at certain times of the day, and the mapper simply failed to add the tag.. this doesnt excuse you as the driver in control of the vehicle from following the relevant laws on-the-ground. Anyone who trusts their GPS's speed-guidance above and beyond the posted speed limit signs, has no-one to blame but themselves. I see the maxspeed tag being useful as a guide to your speed limit, and also useful in calculating accurate ETAs, but I dont think it should be depended upon as a certainty. If the GPS says the speed limit is 80 and there are 40km/hr roadworks in-place, its the drivers responsibility to follow the posted limit, not the limit being suggested by their GPS. David ___ talk mailing list talk@openstreetmap.org http://lists.openstreetmap.org/listinfo/talk
Re: [OSM-talk] Why quality is more important than routing speed
On Mon, Jul 5, 2010 at 9:44 AM, Anthony o...@inbox.org wrote: How do you use speed limit tags when only 5% of the roads are tagged with them? Think longer-term. Okay. How do you use speed limit tags when only 8% of the roads are tagged with them? I don't share your pessimism. I've mapped maxspeed=* quite a bit. Compared to name=*, it's no harder to map, and it is of increasing importance. I think we'll get far more than 8% of road names tagged in the long-term future, and I think the same of maxspeed=*. ___ talk mailing list talk@openstreetmap.org http://lists.openstreetmap.org/listinfo/talk
Re: [OSM-talk] Why quality is more important than routing speed
On 5 July 2010 10:45, john whelan jwhelan0...@gmail.com wrote: Generally speaking you could bot an area with the default speed limit then just tag the higher speed roads. You don't need to bot anything, you can easily do this sort of thing in JOSM... The bigger problem is how do you stop some teenager from changing the sped limit on the map. How do you limit/prevent other sorts of abuse? Why would this tag be any more or less prone to abuse? Mind you wouldn't attacking the device limiting speed be quicker/more efficient, since I'm assuming the speed limit information in the device won't be updated in real time etc... ___ talk mailing list talk@openstreetmap.org http://lists.openstreetmap.org/listinfo/talk
Re: [OSM-talk] Why quality is more important than routing speed
Did it prevent me from mapping when I discovered back in 2007 that the map was almost blank? Did I think that the project had no potential, could not become anywhere near suitable for routing? No, on the contrary. And look at where we're now, only three years later! Reasoning in half empty instead of half full won't lead us anywhere. Stop whining, be constructive. 2007On 2010-07-05 01:44, Anthony wrote: On Sun, Jul 4, 2010 at 6:33 PM, Roy Wallace waldo000...@gmail.com mailto:waldo000...@gmail.com wrote: On Sun, Jul 4, 2010 at 10:34 PM, Anthony o...@inbox.org mailto:o...@inbox.org wrote: How do you use speed limit tags when only 5% of the roads are tagged with them? Think longer-term. Okay. How do you use speed limit tags when only 8% of the roads are tagged with them? ___ talk mailing list talk@openstreetmap.org http://lists.openstreetmap.org/listinfo/talk ___ talk mailing list talk@openstreetmap.org http://lists.openstreetmap.org/listinfo/talk
Re: [OSM-talk] Why quality is more important than routing speed
2010/7/5 Anthony o...@inbox.org: Okay. How do you use speed limit tags when only 8% of the roads are tagged with them? Actually it doesn't matter at all, how many percents of the planet are tagged with a certain tag, it is sufficient that the tags are present in the area you are interested in ;-). Btw. I recommend to add source:maxspeed as well (sign, country:urban, country:rural, etc.) and tag all roads with maxspeed (and then mark implicit maxspeeds with source like suggested in the wiki). cheers, Martin ___ talk mailing list talk@openstreetmap.org http://lists.openstreetmap.org/listinfo/talk
Re: [OSM-talk] Why quality is more important than routing speed
John F. Eldredge wrote: Recently, I have been using Potlatch, with the Yahoo aerial-photos background, to clean up some errors in data that originated with the TIGER import. According to the Potlatch documentation on the wiki, if I drag a node belonging to one way onto a node belonging to another way, the nodes in that segment of the second way should turn blue to show that the ways will be joined. In practice, however, this doesn't always happen If the wiki says that then the wiki is wrong. :) Potlatch doesn't automatically make joins if you drag an existing node onto another way. (Drawing a way is another matter.) You can do one of two things: - Select the top-most way, and shift-click the intersection. A node will be inserted in all the ways at that point. - Drag the node onto the way you want to join it to. Press J (for Join). cheers Richard -- View this message in context: http://gis.638310.n2.nabble.com/Why-quality-is-more-important-than-routing-speed-tp5252052p5255616.html Sent from the General Discussion mailing list archive at Nabble.com. ___ talk mailing list talk@openstreetmap.org http://lists.openstreetmap.org/listinfo/talk
Re: [OSM-talk] Why quality is more important than routing speed
Nic, Nic Roets wrote: There is a lot of talk around better algorithms (e.g. contraction hierarchies), distributed routing, stress tests etc. So I'm going to put in into perspective with a few calculations. For a 40km journey, Gosmore takes 50ms*. It's all a question of user experience. Of course if I want to plan a route it is not a big deal if I have to wait 50ms or even a few seconds. However if you have a fast service you can switch over to a more interactive way of route planning (think Google's UI where you grab a via point and drag it and get a new route instantly, even while dragging; or where it computes a number of routes for you initially instead of just one). This is also an aspect of quality, and allows the user to find a better route. Quality is not just how many tags you support, although in a rich environment like OSM it is of course desirable to use as much information from the data as possible. Bye Frederik -- Frederik Ramm ## eMail frede...@remote.org ## N49°00'09 E008°23'33 ___ talk mailing list talk@openstreetmap.org http://lists.openstreetmap.org/listinfo/talk
Re: [OSM-talk] Why quality is more important than routing speed
On Sun, Jul 4, 2010 at 2:20 AM, Frederik Ramm frede...@remote.org wrote: Nic, Nic Roets wrote: There is a lot of talk around better algorithms (e.g. contraction hierarchies), distributed routing, stress tests etc. So I'm going to put in into perspective with a few calculations. For a 40km journey, Gosmore takes 50ms*. It's all a question of user experience. Of course if I want to plan a route it is not a big deal if I have to wait 50ms or even a few seconds. However if you have a fast service you can switch over to a more interactive way of route planning (think Google's UI where you grab a via point and drag it and get a new route instantly, even while dragging; or where it computes a number of routes for you initially instead of just one). This is also an aspect of quality, and allows the user to find a better route. That's a great point. Being able to quickly recalculate a route, when going off course (intentionally or unintentionally), or when traffic conditions change, is very important. On the other hand, I'm sure it's possible to cache some extra detail when creating the route which should make this relatively simple. If nothing else, finding a shortest (*) path when you've already got a relatively short (*) path calculated, is much quicker than finding a shortest path from scratch. Really I think the biggest cost factor contributing to quality is going to be keeping up to date with things like traffic, construction, etc. I don't foresee OSM being very useful on that front, especially up-to-the-minute traffic conditions. (*) With short defined however desired, not necessarily in kilometers. Quality is not just how many tags you support, although in a rich environment like OSM it is of course desirable to use as much information from the data as possible. The problem with that is that once you get past the most popular tags you're going to have very spotty coverage. How do you use speed limit tags when only 5% of the roads are tagged with them? Based on the title of this thread I thought Nic was actually going to say pretty much the opposite of what he said: that using high quality OSM data is more important than trying to squeeze a few minutes of time savings using less well-maintained OSM ways. ___ talk mailing list talk@openstreetmap.org http://lists.openstreetmap.org/listinfo/talk
Re: [OSM-talk] Why quality is more important than routing speed
On Sun, Jul 4, 2010 at 10:34 PM, Anthony o...@inbox.org wrote: How do you use speed limit tags when only 5% of the roads are tagged with them? Think longer-term. ___ talk mailing list talk@openstreetmap.org http://lists.openstreetmap.org/listinfo/talk
Re: [OSM-talk] Why quality is more important than routing speed
Frederik Ramm wrote: Nic, Nic Roets wrote: There is a lot of talk around better algorithms (e.g. contraction hierarchies), distributed routing, stress tests etc. So I'm going to put in into perspective with a few calculations. For a 40km journey, Gosmore takes 50ms*. It's all a question of user experience. Of course if I want to plan a route it is not a big deal if I have to wait 50ms or even a few seconds. ... Quality is not just how many tags you support, although in a rich environment like OSM it is of course desirable to use as much information from the data as possible. That is an interesting line of argument and gets at the (usual) question of how much end user support we want to provide. I.e. do we want to build a routing service for anyone to use, or do we want to include routing on the main page as an important debugging tool to ensure high quality routing data for others to build upon. I can't answer that question and I don't know who could, but I suspect that (initially) focusing on integrating a router with the aim to use it as a debugging tool would be less contentious. In that setting, the question of how many tags you can support (and how frequent you can update the data) very much becomes the main question. So as long as OSMF can afford the resources to run it (and it appears as if it is at least in the correct order of magnitude) going for the option that is (more or less) available now and supports a large variety of relevant OSM tagging seems like a reasonable solution. Then improve things iteratively where there is demand. If the load does turn out to be too large, then one can try and reduce it by e.g. hideing it off the bottom of the screen as was done with the search box, or by e.g. only offering it to logged in users as it is only meant as a support for editing data. Kai -- View this message in context: http://gis.638310.n2.nabble.com/Why-quality-is-more-important-than-routing-speed-tp5252052p5254398.html Sent from the General Discussion mailing list archive at Nabble.com. ___ talk mailing list talk@openstreetmap.org http://lists.openstreetmap.org/listinfo/talk
Re: [OSM-talk] Why quality is more important than routing speed
Speaking of using routing as a verification tool reminds me of a Potlatch question. Recently, I have been using Potlatch, with the Yahoo aerial-photos background, to clean up some errors in data that originated with the TIGER import. According to the Potlatch documentation on the wiki, if I drag a node belonging to one way onto a node belonging to another way, the nodes in that segment of the second way should turn blue to show that the ways will be joined. In practice, however, this doesn't always happen, and I sometimes appear to end up with overlapping, but not joined, ways. What can I do to force the ways to be joined? -- John F. Eldredge -- j...@jfeldredge.com Reserve your right to think, for even to think wrongly is better than not to think at all. -- Hypatia of Alexandria -Original Message- From: Kai Krueger kakrue...@gmail.com Sender: talk-boun...@openstreetmap.org Date: Sun, 4 Jul 2010 15:46:49 To: talk@openstreetmap.org Subject: Re: [OSM-talk] Why quality is more important than routing speed Frederik Ramm wrote: Nic, Nic Roets wrote: There is a lot of talk around better algorithms (e.g. contraction hierarchies), distributed routing, stress tests etc. So I'm going to put in into perspective with a few calculations. For a 40km journey, Gosmore takes 50ms*. It's all a question of user experience. Of course if I want to plan a route it is not a big deal if I have to wait 50ms or even a few seconds. ... Quality is not just how many tags you support, although in a rich environment like OSM it is of course desirable to use as much information from the data as possible. That is an interesting line of argument and gets at the (usual) question of how much end user support we want to provide. I.e. do we want to build a routing service for anyone to use, or do we want to include routing on the main page as an important debugging tool to ensure high quality routing data for others to build upon. I can't answer that question and I don't know who could, but I suspect that (initially) focusing on integrating a router with the aim to use it as a debugging tool would be less contentious. In that setting, the question of how many tags you can support (and how frequent you can update the data) very much becomes the main question. So as long as OSMF can afford the resources to run it (and it appears as if it is at least in the correct order of magnitude) going for the option that is (more or less) available now and supports a large variety of relevant OSM tagging seems like a reasonable solution. Then improve things iteratively where there is demand. If the load does turn out to be too large, then one can try and reduce it by e.g. hideing it off the bottom of the screen as was done with the search box, or by e.g. only offering it to logged in users as it is only meant as a support for editing data. Kai -- View this message in context: http://gis.638310.n2.nabble.com/Why-quality-is-more-important-than-routing-speed-tp5252052p5254398.html Sent from the General Discussion mailing list archive at Nabble.com. ___ talk mailing list talk@openstreetmap.org http://lists.openstreetmap.org/listinfo/talk ___ talk mailing list talk@openstreetmap.org http://lists.openstreetmap.org/listinfo/talk
Re: [OSM-talk] Why quality is more important than routing speed
Hi, Kai Krueger wrote: That is an interesting line of argument and gets at the (usual) question of how much end user support we want to provide. I.e. do we want to build a routing service for anyone to use, or do we want to include routing on the main page as an important debugging tool to ensure high quality routing data for others to build upon. Correct - almost. If we want to have routing as a debugging tool then it shold probably *not* be prominently placed on the main page but instead somewhere else where it is easily accessible to mappers but out of the way of the passing visitor. (Also, having a really high-speed routing option can do a lot for debugging, e.g. you can automatically calculate matrices like Andy did for the US, and update them continuously.) Bye Frederik -- Frederik Ramm ## eMail frede...@remote.org ## N49°00'09 E008°23'33 ___ talk mailing list talk@openstreetmap.org http://lists.openstreetmap.org/listinfo/talk
Re: [OSM-talk] Why quality is more important than routing speed
On Sun, 2010-07-04 at 19:44 -0400, Anthony wrote: On Sun, Jul 4, 2010 at 6:33 PM, Roy Wallace waldo000...@gmail.com wrote: On Sun, Jul 4, 2010 at 10:34 PM, Anthony o...@inbox.org wrote: How do you use speed limit tags when only 5% of the roads are tagged with them? Think longer-term. Okay. How do you use speed limit tags when only 8% of the roads are tagged with them? Well, legally in Australia anyway, any road not sign-posted with a limit, has an implied limit of 50. It would be nice to have a layer like noname, which shows ways without speed limit defined, to fix the data for exactly this reason. David ___ talk mailing list talk@openstreetmap.org http://lists.openstreetmap.org/listinfo/talk
Re: [OSM-talk] Why quality is more important than routing speed
However, you can't be certain, without personally checking the street in question, whether the street really has no speed limit signs, or whether the person who added the street to the map simply failed to add the speed limit tag. -- John F. Eldredge -- j...@jfeldredge.com Reserve your right to think, for even to think wrongly is better than not to think at all. -- Hypatia of Alexandria -Original Message- From: David Murn da...@incanberra.com.au Sender: talk-boun...@openstreetmap.org Date: Mon, 05 Jul 2010 10:06:55 To: Talk Openstreetmaptalk@openstreetmap.org Subject: Re: [OSM-talk] Why quality is more important than routing speed On Sun, 2010-07-04 at 19:44 -0400, Anthony wrote: On Sun, Jul 4, 2010 at 6:33 PM, Roy Wallace waldo000...@gmail.com wrote: On Sun, Jul 4, 2010 at 10:34 PM, Anthony o...@inbox.org wrote: How do you use speed limit tags when only 5% of the roads are tagged with them? Think longer-term. Okay. How do you use speed limit tags when only 8% of the roads are tagged with them? Well, legally in Australia anyway, any road not sign-posted with a limit, has an implied limit of 50. It would be nice to have a layer like noname, which shows ways without speed limit defined, to fix the data for exactly this reason. David ___ talk mailing list talk@openstreetmap.org http://lists.openstreetmap.org/listinfo/talk ___ talk mailing list talk@openstreetmap.org http://lists.openstreetmap.org/listinfo/talk
Re: [OSM-talk] Why quality is more important than routing speed
Generally speaking you could bot an area with the default speed limit then just tag the higher speed roads. The bigger problem is how do you stop some teenager from changing the sped limit on the map. www.carsguide.com.au/site/news-and-reviews/car-news/gps_speed_limiters_in_action Cheerio John On 4 July 2010 19:44, Anthony o...@inbox.org wrote: On Sun, Jul 4, 2010 at 6:33 PM, Roy Wallace waldo000...@gmail.com wrote: On Sun, Jul 4, 2010 at 10:34 PM, Anthony o...@inbox.org wrote: How do you use speed limit tags when only 5% of the roads are tagged with them? Think longer-term. Okay. How do you use speed limit tags when only 8% of the roads are tagged with them? ___ talk mailing list talk@openstreetmap.org http://lists.openstreetmap.org/listinfo/talk ___ talk mailing list talk@openstreetmap.org http://lists.openstreetmap.org/listinfo/talk
[OSM-talk] Why quality is more important than routing speed
There is a lot of talk around better algorithms (e.g. contraction hierarchies), distributed routing, stress tests etc. So I'm going to put in into perspective with a few calculations. For a 40km journey, Gosmore takes 50ms*. So let's say Errol costs around $10,000 and you want to pay it off in 2 years by selling routes. Over the two years it can calculate roughly 12 billion 40km routes. That's 0.0001 cents per route. So you can make a profit by selling 2 year subscriptions at 1c each. Compare that with how expensive cars are per km. An algorithm that is 10 times faster does not change the economics. By contrast, let's say you add support for just a few more tags. Perhaps routing the driver around congested intersections. He sees that the product is saving him time and fuel. Then he will pay when you increase your price with a few dollars. *: I admit that the core algorithm is quite bad but it does make up for it by being able to do everything in RAM and reducing cache misses. ___ talk mailing list talk@openstreetmap.org http://lists.openstreetmap.org/listinfo/talk
