iSpy | How we turn "Fuzzy" location data into good iSpy games

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How we turn "Fuzzy" location data into good iSpy games

Its been an exciting month watching the number of games and players grow. While I'm normally against making changes to the live system, it's very clear for the data-bat(tm) Greg is beating over the head with, that some games are pretending to be in places their not. Turns out the culprit is the iPhone's GPS accuracy, or lack there of. The quality of the location data is important to the game playability. The last thing we want is for players running around trying to solve games that do not exist. So far the only person this has happened to is Mulvaney (but thats ok, he has enough points already =] ).

Bad accuracy is not bad data, but it can be

Now, I'm not one for posting big blog updates, but this one seems to be more in my camp then Greg's. During our beta we had a lot of good examples of good and bad games, but not a lot of games having bad or inaccurate data. For example, we have games that are "bad" like game 9370 that to my best guess was created on a moving train. (Yes, this game is inactive, something we hope to enable for all players soon.) While we have had a few "bad accuracy" games 8850, 8814 (Go thedroog!!!) that seem just a little off, cause I doubt they are building the Walmarts on the freeway now, are they? So, we have been racking our brains trying to figure this out. (Well, I have been just waving Greg off saying "bad data in, bad data out...") With all the new games everyone has been creating we have started to see some interesting patterns.

Controlling how fuzziness effects difficulty

While we are all created equal, it seems our (i)phones, or more like our reception, is not. I'm not totally sure of all of the issues, but it seem some people take a bit longer to get their position then others. To give you an idea, the average player's gps accuracy is off by about 17~47 meters after only running the app a short while. Since the goal is to find the object in question, this is fine. Well better then fine, it was too good, back at the start we had to develop a means to "fuzzy" the location of the object, make it harder to find, this is where we get difficulty from. We decided to make "fuzzy" rings that the object would be hidden in. So these ranks of difficulty 1 - 5 became the backbone of the game system. "1" being a game less them 0.03 miles in radius, "2" 0.06 miles, "3" 0.105 miles, "4" 0.20 miles, and "5" 0.311 miles. Before you ask "How did you choose those numbers?", I will just cut you off and say [business-term]. If you don't buy that reason, talk to Greg. Back to my point, it seems that several players have started to get a bit farther off then 47 meters. O' say 5000+ meters!!! but these are clearly connection issues... right, RIGHT... Wrong, maybe?

Bad accuracy should not effect playability

It seems that between real GPS, cell tower triangulation, and IKnowWhereYourIPAddressIs(tm) madness some things get "confused". We have seen good games get created, that were very far away from their reported positions. Most of them are under 500 meters away, but many range between 47 meters and 500 meters. So as of Tuesday(5th), we are going to help fuzzy the fuzzyness. If a game is to "fuzzy" for the difficulty you selected, we will bump it up till it works. Unless your like game 9370, games created where accuracy is over 500 meters will get bumped right out of the system. So if you pull out your phone and try to make a quick game (before your GPS has enough time to accurately pinpoint you) you're a lot more likely to make a good game. For those of you that are "HEY, I WANTED THAT GAME TO BE A DIFFICULTY 1 !!!!one", just wait a bit, the longer the app is running the better your position data is.

...Anyway, grnb77 you just happened to make your game right as I was sneaking in code to test for games with REALLY bad accuracy. So you have the first official game to be ejected by the system for being "bad", thanks, gratz, and great timing!!!

The picture looks to be something in Japanese, if anyone wants to translate this post or that text in that picture please add it to the comments.

Thanks to grnb77 for his game and also to anyone that wishes to translate.

-Ian "Your Friendly Data Overlord" M.

By: Ian M. on Jan 06, 2010