Are passenger and mail volume reciprocal?

[T/C]

Does the "Passenger level" refer to both the outgoing and incoming volume of passengers? That would seem intuitive. How about "Mail level"? That seems less intuitive.

I'm trying to answer this question myself by watching the dynamics of my game in progress. My best guess is that passenger level is reciprocal, but mail level is not. Is that right?

-TC

[T/C]

I see this question has attracted no responses, so maybe I need to explain my question better. Basically, I'd just like to know if arrivals = departures.


When I design my transportation systems, it seems important to know the ratio between arrivals and departures at a station. If Arrivals>Departures, then it should be okay to deliver only full trains to that station. The people getting off will make plenty of room for the people who want to get on. If Arrivals<Departures, however, then full trains will just cause an endless buildup of waiting departures, and I need to fine-tune the system to ensure that there is sufficient unused capacity in arriving trains.

I usually assume that, in the long-term, Arrivals=Departures. After all, that makes sense in the real world. Except for emigration and immigration, everyone who leaves home eventually comes back, resulting in an equal number of departures and arrivals at both their home and destination station. However, when I build this assumption into my schedules, it is not obviously correct. There are instances where I get surprisingly large imbalances. These imbalances often seem to happen at the outskirts of town. For instance, after a few years of waiting, my central station may collect only a few passengers destined for an out-of-the-way bus stop, but in that same time period, that bus stop may become crowded with hundreds of people waiting to leave.

On the other hand, there are times when the Arrivals=Departures assumption seems to be validated. Sometimes, a station I'm clearing at 1:1 will become terribly overcrowded, but I'll be able to track the overcrowding to some specific problem (e.g. a traffic jam, a train full of passengers en route who were vaporized at a depot, etc.).

My best guess is that in Simutrans, "Passenger level" refers to the departure rate; there are game mechanics which ensure that the arrival rate = departure rate in the long term, but not the short term; and something about those mechanics makes funny things happen at locations with small passenger levels. Are these guesses correct? Are these things documented anywhere, or the subject of earlier discussions? If other players don't find it important to know this, why not?


Also, there is the question of mail. First of all, mail doesn't follow the same logic as passengers in the real world. For any given location, the amount of mail sent and the amount received can be far different. That seems to be true in Simutrans as well. In one of my games, I made a special study of a city neighborhood that included a garbage dump. In every year for a decade, it sent about 10x as much mail as it received.

My best guess is that in Simutrans, "Mail level" refers to mail departures, and mail arrivals are roughly equal for all buildings everywhere. Thus, buildings with above-average mail levels are departure constrained while buildings with below-average mail levels are arrival constrained. Are these guesses correct?


-TC

[Combuijs]

Passengers are fully reciprocal, e.g. when a passengers is generated to go from A to B, there will be another one who goes from B to A. However, when the passenger is generated he goes to one of the stations in his catching-area (most times this there is only one station). If that station is overcrowded, he won't travel and is added to the unhappy passengers.

For mail this is more or less the same, albeit that attractions generate more mail than they receive.

[prissi]

First the arriving and returning passengers is only true for trips outside of the town, or heading to factories or attractions. The same is true for mail, however attractions generate 8x more mails than they recieve. Furthermore in some versions mail did start its jouney even if the final stops did not accept mail, which resulted in oneway delivery.