A CITY MOVE ALGORITHM REVIEW
This post is a thought exercise that's based on casual observation, hunches, and good programming techniques. This thread is NOT any sort of complaint thread, as the city moves are working delightfully well; rather it proposes a possible scenario that's consistent with recent observations.
You are very much invited to offer observations that will allow us to refine and/or validate our understanding of the City Move Algorithm.
GOLDMINES
A Goldmine indicates that a city sector on your local World Map:
- Has never been occupied
- Had a deleted city
- Had an archived city
AUTODELETE CITIES
I've never seen a Goldmine that only lasted a few hours, so I'm assuming that InnoGames maintains a list of Autodelete Cities, sorted by distance from the world map center. Eligibility for the autodelete list MIGHT be:
- Diamonds have never been purchased nor earned
- The city is still in chapter 1
- The owner has not logged in for at least a
month week
SWAPPABLE CITIES
Perhaps the same list includes ALL Inactive Cities, but the larger cities will be swapped with an Isolated City (more below) rather than Autodeleted, or else archived, and eventually deleted.
(Edit) Note that an Isolation Metric needs to be calculated for a Swappable City as well, to avoid swapping an Isolated City to an even worse location.
If the owner of a Swapped City starts playing again, they won't know most of their neighbors, and they'll probably see a few Goldmines, but they'll soon be recognized as an Isolated City that's eligible for relocation.
ARCHIVED CITIES
When you search for a player by name, you'll occasionally get a city that returns you to your OWN map when you click on the World Map icon in their city, so there are apparently archived cities that no longer have a World Map location, perhaps for several months.
NEW USERS
Throughout the week, New Users seem to replace the Autodelete Cities and Goldmines that are the nearest to the center of the World Map.
RECENT LOGONS
https://us.forum.elvenar.com/index.php?threads/city-movement.28895/post-252898
indicates that:
- Position on the map
- Matching Boosts
- Recent logons
Are the only criteria for "active", which is a weak metric for Trading Activity.
ISOLATED ACTIVE CITIES
An "Isolated" criteria could be very simple. Innogames likely prunes the Notification Logs every week, by date, and if they then count the remaining (recent) Notifications (Visits + Trades) that are NOT from the player's own Fellowship, they'll have a pretty solid Isolation Metric.
They could then sort the consequent list by the Isolation Metric (few to many Neighborhood Notifications). They'd also need to ensure that the City Type (which is determined by the Relic Tile that's immediately above the city) would be easy to identify.
- When there is no active Tournament (around Sunday midnight in Germany), start down the Isolated City list.
- Find the Inactive City nearest the center of the World Map, that's of the same type.
- If it's an Autodelete City, replace it and leave a Goldmine
- If it's a Swappable City, do so.
Does this model match what you're seeing?