1.Time efficient approach to rating

Start by copy pasting the route in to another map applications to get a quick overview of where there are deviations. Focus on investigating these deviations, especially if they are ranking high on the “potential error list”. But be aware of situations where the difference is just from a different preference of route, some map applications just seem to prefer certain type of roads etc. If you do not recognize what is an obvious preference difference, you can end up doing a lot of unnecessary investigation where there is no real issue. Sometimes adding 1-2 extra stops can get around this issue and then compare like for like routes with less “normal” deviations.

Approach rating efficiently by evaluating the route and identifying the high-risk areas. Start by looking at these for an MNE. What are high risk areas?

Route Start, first 2 steps
Route End, last 2 steps
U-turns
Junctions and road signs
Roundabouts
City areas of the routing rather than rural areas.

Obviously, you should not rule out anything but spending time on these, instead of tracking the routing along a major road, especially rural ones, where perhaps two other map applications agree with the routing, is simply more effective way of evaluating the route.

High-risk areas need to be evaluated on a street view basis.
Most of the other areas, especially driving along a rural road, are most of the time fine on a satellite view in combination with other map applications.
The difference in being time effective and looking at every inch of the way is knowing where to start to look. The high-risk areas can be anywhere along the route as will show in examples to follow.
2.Misalignments

Misalignments are considered MNEs when the misalignment is more than 50 meters from blue route line to the ’present day’ ground truth. It is very common for the blue route line to be misaligned along long stretches of the route. It is very important to scan thoroughly even the sections that follow major roads without turns. Often the misalignment is less than 50 meters, in which case it should be rated as a minor issue, but the misalignment distance should always be measured. If it is more than 50 meters, a comment and the coordinates are required. This is one type of misalignment. See the Guidelines section 4.1.1. for the definitions of the other types.

3.Access Restricted

Below is an example where the route passes through a restricted access area. There are gates at points shown by the red arrows, which prevent an average driver to pass through. Since this is not

 

the start nor destination point of the route, it is marked as an MNE – Access Restricted, see 4.3.Access Restricted

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4.Turn restriction

Turn restrictions are always indicated with traffic signs. Therefore any turns that can’t be confirmed by painted arrows/turn channels on satellite images, should be checked on street view, see 4.7.

Turn Restriction

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5.Cars not allowed

Many times the suggested route uses pedestrian/bicycle roads. Any suspicious sections should be checked on street view, as often the pedestrian areas seem wide enough for a car. For example in the screenshots below the pedestrian zones might seem like streets for cars on satellite image but street view images clearly have signs that indicate that these roads are only allowed for

pedestrians or cyclists, see 4.4.Cars Not Allowed

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6.Against traffic

As you can see the below the blue line route instructs the user to go against the flow of traffic on the roundabout which is a MNE, see 4.1.1.2. Roundabouts and Traffic Circles

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.In the below example the route begins on a one way road but the route instructs the user to go the wrong way on this road. This is against traffic and so should be rated as a MNE.

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At the top of the road we can see that there is road markings indicating that traffic is not allowed down this road as the route direction suggests.

 

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7.Physically Impossible – Road does not exist

Below is an example where user is instructed to go over a barrier and onto a pedestrian walkway. This is thus an MNE – Physically Impossible on this route.

 

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In this below example the route goes on a pedestrian path and over a divider where it’s not possible to drive. Again this is a physical impossibility and should be rated as a MNE.

 

8.Walking Instructions are neglected

Some routes include a pedestrian part, which is indicated it in the instructions, so the route is rated normally. You’ll need to check the steps to see if they mention Prepare to Park or any other instruction related to Walking. Mainly in the cases where route takes user to where cars are not allowed.

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9.Comments

Whenever an MNE is discovered, the analyst is requested to leave a comment that includes the Step ID and brief explanation of the MNE, and links to any supporting evidence. Examples of good comments are provided in the table below.

MNE

Comment

Major Road Misalignment

At Step N, 60.111111,24.222222, the route misses a roundabout larger than 50 m in diameter. [link to resource]

At Step N, 60.111111,24.222222, the route misses a turn channel that measures more than 100 m from the beginning to the end of the turn channel divider. [link to resource]

At Step N, 60.111111,24.222222, the route misses a turn channel, because there exists a point along the center of the turn channel lane, from which the distance to the closest point on the blue line is more than 50 m. [link to resource]

Physically

Impossible

At Step N, 60.111111,24.222222, the route uses a road that does not exist in the real world. [link to resource]

At Step N, 60.111111,24.222222, the user is requested to make a manoeuvre which is no more possible because the road network has changed, as can be verified from more recent satellite images [link to resource].

Access Restricted

At Step N, 60.111111,24.222222, the route travels through an area restricted only to residents, as can be verified from street level images [link to resource]. Because the route does not start or end within the restricted area, this is an MNE.

Cars Not Allowed

At Step N, 60.111111,24.222222, cars are not allowed to use the pedestrian only walkway indicated by the traffic sign visible in the street level images [link to resource].

Against Traffic

At Step N, 60.111111,24.222222, the route goes against traffic as there is a traffic sign forbidding driving this way, see the street imagery [link to resource].

Illegal U-Turn

At Step N, 60.111111,24.222222, it is illegal to make a U-turn on a motorway. [link to resource]

At Step N, 60.111111,24.222222, there is a traffic sign, which prohibits U-turns, as can be verified from street imagery [link to resource].

Turn Restriction

At Step N, 60.111111,24.222222, it is not allowed to turn left between 6 – 18 hours any day of the week, as indicated by the traffic sign visible in the street level images [link to resource]. Since the user will reach this step during the time of restriction, this is an MNE.

Other

At Step N, 60.111111,24.222222, [provide a detailed explanation what is wrong with the route]. [link to resource]

 

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