"Lure Mechanics"

#PokemonGO: Howdy folks of my favourite sub!About a week ago I saw a couple of posts (post 1 & post 2) which suggested that the types of pokemon that appear near a lured pokestop are based on the position of the player when the lure is attached to the pokestop. According to this hypothesis:The game approximates the biome in which you are standing when you drop the lureThe lure attracts pokemon corresponding to the biomeI've recently been doing a lot of tests around Uppsala, Sweden (where I live), which have resulted in my analysing which pokemon appear from lures at various 3-stops (three pokestops in close vicinity) around town. While I haven't fully written up that analysis, and while I didn't track pokemon from individual lures (I summed the pokemon lured in one hour from all three), I still had a qualitative sense of it not being the case that biome in which you stand affects the pokemon that spawn from lures.In order to test if it was so, I conducted an experiment in town here. There is a square known these days as "Pokemon Square" which has three pokestops reachable from it and which are all effectively permanently lured. I got there early one day so I could start lures at the same time and lure all three pokestops four times each and observe which pokemon appeared as a function of where I stood.The square looks like this; there's a pokestop in the middle and one to the north in a town street and one to the south on a bridge. The bridge is certainly water biome because the wild spawns there are things like Magikarp, Psyduck, Poliwag and even the occasional Dratini. The street and square are the more regular city spawns with stuff like Pidgey, Rattata, Spearow and every now and then something a bit more interesting like a Venonat or Caterpie (yes, Uppsala has boring pokemon). It's also important to note that there are many Drowzees in town although these are mostly concentrated on the far side of the river among the university buildings.So here's what I did - I sat at the square and lured all three stops twice (lures 1 & 4). For lures 2 & 3 I walked over to the bridge, stood in the water biome and lured two of the stops (the Bridge and the Square) - I couldn't lure the Street all the way from the Bridge. So lures 2 & 3 were lured from the water biome for two of the stops and from the square for the street pokestop.As a result I now had 12 sets of 10 pokemon lured from the stops around the square. According to the above hypothesis:The lures I placed when standing on the bridge should attract water pokemonThe lures I placed when sitting at the square should attract different pokemonHere are the results.As you can see, the hypothesis was disproved. Standing on the bridge does not guarantee a water biome spawn. Of all the lures I placed, one did turn out to be a water lure, and it was one on the bridge, and it did occur when I placed it from standing on the bridge. However, reviewing the results will clarify that not all lures on the bridge are water biome and not all lures placed while standing on the bridge are water biome.When it comes to actually making sense of the results, I tried to group the lures into categories.Based on these "types" there doesn't seem to be any correlation between where you stand and which stop you lure.If I were to form a hypothesis on how lures work, and how they interact with biomes in particular, based on this test as well as previous testing in town, I would suggest something like this:When you place a lure on a pokestop, the game considers which biomes are nearby.Each biome represents a set of pokemon that spawn with various frequencies from a lure of that type.The game then randomly (weighted by proximity / abundance) allocates the lure a biome type that is either 100% one biome (like the water one in my test) or (more rarely) a mixture (not necessarily 50%-50%) of two or more biomes.If the player position in any way affects the biome type of the lure, then this would be because by changing your position you alter the likelihood of a specific biome type being selected, and not from any direct effect. In other words, if you stand in one place and see mostly one kind of lure spawn and if you stand in another place and see mostly a different kind, then this would suggest that the game calculates the lure biome type created based on player position and not on the position of the pokestop itself. This would require further testing to illustrate however.So in my example, the types that could spawn were either the "Drowzee Type", which I guess corresponds to the very large areas on the other side of the river, as well as a few minor places on the same side, where university buildings are common and Drowzees are ubiquitous; "City Type", which is the kind of spawns you'd expect walking through town catching them wild; "River Type", which is clearly the water biome; and the "Unknown Type", which I think may be caused by the Cathedral on the other side of the river.Sorry for the "negative" result, but I figured data of any kind might help shed some light on the lure mechanics.To be constructive, I would suggest identifying the different "types" of lures that are created at various stops. If you could then map out the frequency with which they spawn at various place throughout town, I hypothesise that you would see increasing frequency of a certain type when you are in a more homogenous area - so somewhere that is dead center of town will see many City Type lures and few or no River Types. Somewhere that is surrounded by a large body of water will see many Water Type lures and few City Types, etc.By learning which pokestops reliably provide which lure type, you could work out how to make the most out of your lures!Cheers!TL:DR - my data suggests that player position does not directly determine the type of lure created (e.g. water, park, city, etc.) but may indirectly affect it based on nearby biome abundance via /r/TheSilphRoad http://ift.tt/2cssWzt