Reading the descriptions of minibus and share taxi on Wikipedia, I get the impression that these are different names for the same thing. In fact, even some of the same regional names appear in both articles.
The terminology used in my region translates literally to “microbus” which might mean I should map the respective access restrictions using minibus, but if they are synonyms, share_taxi might be better, since it’s much more common in the data.
Edit: my questions were already mostly answered in the articles about route=minibus and route=share_taxi relations, it just took me a while to find them.
As with a lot of public transport, daily language sometimes blurs the distinction between type of vehicle and type of service, which doesn’t help us in coming up with standard tagging.
While there does seem to be a lot of overlap here, I think shared taxis tend to be smaller vehicles in at least some countries - either a standard car or a relatively small van-like vehicle (the article mentions capacity for at least 12 passengers as typical for a minibus).
E.g. a “taxi colectivo” in Chile is a car. It is like a bus in running a fixed route and accepting passengers who are not connected to each other, but the vehicle is physically like a taxi. As far as I remember (it’s been a while) fares are higher than for a minibus running a similar route, but lower than a non-shared taxi.
What is the access situation you are mapping, e.g. is it a way reserved for a specific category of public service vehicle?
Public transit “minibus” service was intended for mostly fixed routes and schedules, more regulated, closer to city buses but more often can hail_and_ride freely outside specific stops. share_taxi= are more flexible, less regulated, as a passenger-shared taxi; or it’s a taxi car vehicle running a “minibus” service, as mentioned by others.
The confusion comes from the case of mini-bus vehicles being used for share_taxi= services. The number of share_taxi= is simply from this being more common. The next tier up in most countries is usually a mini-bus vehicle running a standard bus service, with no other difference from midi-bus and standard full-sized buses.
The psv tag includes both minibus and share_taxi, so whenever there are specific permissions for this “microbus” type we have here (which includes slightly larger vehicles that may be called “midibuses” elsewhere), I have to decide whether to modify the access restrictions/permissions set by psv, or drop psv and map permissions of its children tags separately (bus, taxi, and the “microbus” equivalent). If minibus and share_taxi are synonyms, it might make sense to just recommend using only one of those two tags instead of suggesting they are different things.
So, fundamentally, minibus and share_taxi are defined differently in OSM compared to Wikipedia, where “minibus” is a specific category of vehicle types and “share taxi” is a mode of transport (a transport system) which may include a wider range of different vehicles, from smaller than minibuses to larger, heavy buses, and is often run by private operators. Over at Key:access, minibus is defined as “a light bus acting as a public service vehicle” and share_taxi as “a light bus acting as demand responsive transit” which Wikipedia defines as “a form of shared private or quasi-public transport”, and at Key:psv it says that minibus “excludes private use minibuses” but seems to imply that share_taxi is a type of public, not private transport (that may need some clarification that share_taxi should not be used for legal restrictions on private operators). While Wikipedia says that share taxis operate on “semi-fixed routes”, on DRT it says that “vehicles alter their routes each journey based on particular transport demand without using a fixed route or timetabled journeys”, so while in the OSM wiki these concepts (share taxi and DRT) are aligned, in Wikipedia they are clearly distinct. Is that correct?
Does this diagram used in Wikipedia for DRT apply to OSM?
In my region of Germany we either have buses running to a fixed schedule along a fixed route or shared taxis that only run when there’s no bus or train on that route within the next half hour +/-
This service is delivered by taxi companies using their taxi cars but organized by the same entity that organizes the bus service. It needs to be called at least 30min prior to departure and only stops at bus stops and runs routes similar to the buses. If no taxi is called for a given time no taxi will run.
This is different from what I would understand a minibus to be
That’s rather a on-demand public transport, not a shared taxi: you can only use “existing” bus lines, isn’t it? Using taxis doesn’t change the nature of the relation.
Interesting. It is distinct from bus as it only runs when called, but also distinct from Wikipedia’s “shared taxi” concept as it has fixed routes and specific stops.
The services I’m seeing here are publicly regulated and run along fixed routes with a fixed departure timetable, so I guess they are closer to what minibus might mean in OSM. In some cities there are designated stops for them, in other cities there aren’t (or there are very few) and then the small buses can be hailed from and stop at any point along the route. In some cities, these services can use the full bus infrastructure, while in others they may not be allowed in dedicated busways, only in regular bus lanes (and almost always this type of restriction/permission is closely related to restrictions on regular taxis). There are other shared private van services one can hire that offer the flexibility of a taxi (anytime, often flexible routes) but they have no special traffic right (can’t stop at bus stops, can’t use public bus lanes or dedicated busways) and so are very similar to rideshare.
Some bus routes are on-demand (meaning you first need to call the transport organisation or use an app) but otherwise function like any other regular bus route but there also exist on-demand services with flexible routing.
There’s a problem with what “public” and “private” means. share_taxi= can be a “public service” operated “privately”. I don’t see much wrong with using it for private-use though.
I believe share_taxi= is currently being used for some DRT by some. This isn’t very bad either. It could be either “semi-fixed”, or fully flexible. What the semi-fixed means is not “fixed” by authority, but by convention. “Semi-regular" may be a better term. DRT should be possible to have de facto semi-regular routings if there’s enough demand too?
Fundamentally, I do find minibus= flawed. The proposer/author forgot there’s Private Light Bus alongside the “green minibus” Public Light Bus Scheduled Service ( share_taxi= “red minibus” is non-Scheduled) in Hong Kong. There are signs restricting or designating their parking/stopping. Limiting minibus= to the latter is unintuitive and non-hierarchical. (Off-topic: The problems seems inherited from bus= )
Ideally, minibus= might be used for the physical vehicle class. route=minibus could then be used for the functional service distinct from route=bus . Legal restrictions about the service can use minibus:conditional= / minibus:*= / etc. This shows the problem with using minibus= for both access= and public_transport from the special case of HK having Light Bus as both specific classes and services.
