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Posted: Mon Nov 17, 2008 7:48 pm Post subject: Underwhelmed by IQ routes
Am I alone here?
I find the concept of IQ routes to be a fantastic one, and it is something that I was really looking forward to on my new 740.
Still very happy with the product, but I must say that IQ routes has got to be joking in the majority of its advice. It just does not add anywhere near enough time on to a journey for rush hour traffic which is the job it is supposed to be doing.
Try this for me; plan a journey ahead of time on a road you know to be horrible at rush hour and OK at mid-day. See how long IQ routes adds for the rush hour. If it's anything like the roads around here, it seems to add about 1 minute per mile for roads that are bad at peak times vs other times of the day. If you are lucky. This is really unfortunate as it never loads it enough to re-route you around the bad bits (if indeed it can).
This afternoon, the timing was bang on for the first 157 miles of our 160 mile journey, but we hit home at 5.15. It routed us through town and claimed that the last 3 miles of the journey in rush hour traffic would take 9 minutes. They took 23 minutes. My personal estimate was 'it'll be another 20 mins from here'. Shame I was closer, despite not having access to the millions of miles of data that TomTom have.
Can anyone shed light on IQ routes for me? Great idea, but seems deeply flawed to me at present....
Joined: Feb 01, 2006 Posts: 2543 Location: Rainham, Kent. England.
Posted: Mon Nov 17, 2008 8:21 pm Post subject:
Most of the software has problems with giving the correct speed limits on roads, which should be fairly straightforward, let alone getting IQ routes right. It is also impossible for IQ to know when there is an accident, breakdown or the driver decides to take a break. Accurate mapping is my priority, not too fussed about all the 'bling', although 3D maps are pretty good.
Most ETA's on my iGO assume you are travelling non stop at or near the speed limit, so initial ETA can be a bit out . The one advantage of course, is it will update itself according to how good/bad the journey is. _________________ Formerly known as Lost_Property
And NO that's NOT me in the Avatar.
I realise it can't know about accidents etc but then it's not supposed to. What it IS supposed to do is know what the average speed is at a particular time of day. And it is in that where it disappoints. If a particular road is ALWAYS awful at 5.15pm then IQ routes should know and in my (admitedly limited) experience so far it just doesn't seem to...
Joined: Feb 01, 2006 Posts: 2543 Location: Rainham, Kent. England.
Posted: Mon Nov 17, 2008 10:13 pm Post subject:
Quote:
If a particular road is ALWAYS awful at 5.15pm then IQ routes should know and in my (admitedly limited) experience so far it just doesn't seem to...
The idea is good for those travelling regularly at peak times but I think it will be a long time before the system becomes acceptable. Even then I think it would need a monitor on virtually every lamp post to beam data to a control centre which in turn would send a signal to our devices.
Take for example where I mentioned the speed of roads,there are a number in north Kent completely wrong. If I set up to warn when speeding I often either get a warning 10 mph under the speed, and it goes on on and warning me, or even worse, not getting a warning when I am 10 mph over.
Close to me there is the A278 link road between the A2 and M2. It used to be 70mph, and iGO thinks it still is, but is now 50, however, there is a stretch in the middle section where iGO thinks it's 30, as a result I get no overspeed warning for the 50 section unless I exceed 70 and suddenly I get the overspeed warning in the 'silly' section even if I'm only doing 35-40. Add to this devices with IQ, the amount of traffic can vary quite a lot and sometimes it gets very busy, at almost any time of the day, at other times you'd never know it was 'rush hour'. Then there's Hempstead Valley Shopping centre which attracts a lot of traffic on Saturdays, then again the times can vary. I'm not sure any IQ device will ever work that out, I can't and I've been shopping there for about 30 years. just when we think it's the best time to go we'll hit traffic.
Bring back paper maps, all is forgiven. _________________ Formerly known as Lost_Property
And NO that's NOT me in the Avatar.
Joined: Jun 20, 2005 Posts: 1096 Location: Solihull, UK
Posted: Mon Nov 17, 2008 10:50 pm Post subject:
I notice that IQ routes always quotes the date it's basing the route on, but never the day of the week. It makes me wonder whether they've noticed the fact that November 17th was a Saturday last year, but a Monday this time around, and hence the traffic situations will be very different.
I'm prepared to be convinced otherwise, but it does concern me.
Joined: Mar 15, 2006 Posts: 3219 Location: Windlesham, Surrey
Posted: Mon Nov 17, 2008 10:57 pm Post subject:
If you prepare a route and select specific date and time the selection screen shows the day as well as the date. _________________ Anita
TomTom VIA 135 - App 12.075
UK map 1125.12264
Samsung Galaxy S21
FWIW, IQ routes is now smarter on my run around town in the morning. It used to take me around the congested centre of town, but now suggests the "rat-run" that I'd always taken anyway. So at some small level, it is an improvement.
Lost Property - You and I seem to have different a different understanding of how IQ routes works; I believe I have it right, but I'm quite happy to be put straight.
I was under the impression that IQ routes is nothing to do with traffic monitoring systems of any kind. That's HD traffic.
IQ routes alters the speed weighting allocated to roads based purely on historical evidence of TomTom users. Every time you connect to 'home', it downloads all your journeys along with the time you did it in. 'Normal' routing just looks at the length of a road and its speed limit which is why you get routed along a 1 mile road with 6 sets of lights because it has a 40mph limit rather than being routed along the same length 30mph road with no lights which you know from local knowledge is always quicker. IQ routes should give you that local knowledge at a map level as it should pick up all the journeys that have taken longer than the road's speed limit suggests.
On top of this IQ routes 'map', you then have the HD traffic information.
My beef is that on certain A road routes in city centres, neither HD traffic NOR IQ routes seems to take account of daily heavy traffic at peak times and still attempts to route you down the 'fastest' route according to the speed limit rather than based on the local historical knowledge that IQ routes is (if I understand it correctly) supposed to give.
Seriously, they could gain 90% more accurate information by looking at my work journeys for just 1 week.
It adds 9 whole minutes for rush hour, driving from the A1 via the A14 to Cambridge.
I don't need to tell you that the A14 adds at least a 20 minute delay. And as for Cambridge - Cambridge has no sensible road system, it's basically a village, only 50 times bigger. The final 3 miles takes me 20 minutes.
So basically, A journey that takes me 1:20 is reported by my TomTom as going to take 49 minutes. Which is a joke. Because there is no way, short of nuclear haulocaust, that the journey is going to take anything less than 1:10 in rush hour.
Posted: Wed Nov 19, 2008 4:13 pm Post subject: Re: Underwhelmed by IQ routes
Gary_W wrote:
I find the concept of IQ routes to be a fantastic one, and it is something that I was really looking forward to on my new 740.
I agree, but I was thinking about this this morning.
The granulatiry of IQ Routes data is 5 minutes, so:
12 * 24 * 7 = 2016 values for any stretch of road to cover an entire week.
Arbitrarily assuming that you need 5 measurements to get a reliable average, means that you need 10080 measurements to have reliable data for any stretch of road.
Now, according to the CIA (https://www.cia.gov/library/publications/the-world-factbook/geos/uk.html), there are ~ 400 000 km of roads in the UK.
Therefore, to calculate data for the whole of the uk, to a granularity of 1km, you need approx 4 billion meaurements, and more realistically 40 billion down to 100m.
And all of that, is assuming that your measurements are evenly distributed across roads and time slots, which of course is not true, motorways during the day will have tons of data, cul-de-sacs will have practially none. Also, take into account, that people probably don't really use their satnav for regular journeys, such as commuting, and you're gonna find that there's a lot of roads for which there is actually little or no data.
That is a hell of a lot of data needed to get accurate information! IQ Routes *is* a *very* nice idea, but from a practial point of view, it is not going to be perfect, especially across less travelled routes.
Seriously, they could gain 90% more accurate information by looking at my work journeys for just 1 week.
I do hope that you have the option to send them data anonymously is enabled on your device then! The best way to improve this stuff is to enable the logging.
I do hope that you have the option to send them data anonymously is enabled on your device then! The best way to improve this stuff is to enable the logging.
Yeah, definitely a good tip. As I said above, most people don't use their sat nav for regular journeys, but I make a point of not just submitting the data, but at using my sat nav for regular journeys, which should add to the data for the routes I travel the most. I would expect LIVE users to do that a lot more, since HDT and IQR ought to provide at least some motivation to use it for every journey, at least once the data starts to improve (although in my case, I doubt the routes are covered by HDT)
It is a shame that IQ routes isn't a 'Live' service, in that results were uploaded instantly and pushed out to all end users. At the moment, if I'm correct, new IQ routes information gets updated with each new map release.
I don't know how many people know of Dash Navigation but their service works much like this. It's like IQ routes and HD traffic mashed into one realtime service.
It is a shame that IQ routes isn't a 'Live' service, in that results were uploaded instantly and pushed out to all end users.
Well, in a sense it is. Accurate arrival times (theoretically at least) consists of 2 parts IQR and HDT. IQR contains the normal expected travel times, and this is supplemented by HDT which provides real-time information on temporary variations in road speeds relative to IQR.
In theory, if both were complete and accurate, this would be a great system. It would seem apparent that both are currently lacking in completeness.
EDIT - To address your point specifically, fundamentally, the only benefit of pushing out a permanent IQR correction live is that it would reduce the amount of data that has to be sent over HDT (since if the IQR is wrong, then - again theoretically - HDT would report the variation every time - correcting the IQR would remove that) - ultimately, this is a software engineering problem of efficient use of data bandwidth.
If the system worked perfectly and transparently, then to you the end user it wouldn't matter as, the net result would be that for any given stretch of road, the TT would know that the current speed is xx MPH, regardless of whether that data came from IQR or HDT.
EDIT2 - Just realised that permanent IQR corrections would be better for more accurate pre-planning, but once the IQR data is accurate/complete, I wouldn't expect too many significant variations, save for traffic affected by new roads/layouts, for which you would need a new map anyway - okay okay, new speed humps and other minor changes might affect speeds too - I suppose you could justify live IQR corrections, but I wouldn't expect there'd be many such changes, and aside from the pre-planning, HDT could - if it was detailed enough - cover that in the intervening period.
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