The Shape of Code

I was at the Microsoft Gaming data hackathon today. Gaming is very big business and companies rarely publish detailed game data. Through contacts one of the organizers was able to obtain two gaming datasets, both containing just under 300M of compressed of data.

Illyriad supplied a random snapshot of anonymised data on 50,000 users and Mediatonic supplied three months of player data.

Being a Microsoft event there were lots of C# developers, with data analysis people being thin on the ground. While there were plenty of gamers present I could not find any that knew the games for which we had data (domain experts are always in short supply at hackathons).

I happened to pick the Illyriad data to investigate first and stayed with it. The team sitting next to us worked on the Mediatonic data and while I got to hear about this data and kicked a few ideas around with them, I did not look at it.

The first thing to do with any dataset is to become familiar with what data it actually contains and the relationships between different items. I was working with two people new to data science who wanted to make the common beginner mistake of talking about interesting things we could do; it took a while for my message of “no point of talking about what we could do with the data until we know what data we have” to have any effect. Of course it is always worth listening to what a domain expert is interested in before looking at the data, as a source of ideas to keep in mind; it is not worth keeping in mind ideas from non-domain experts.

Quick Illyriad game overview: Players start with a settlement and construct/upgrade buildings until they have a legendary city. These buildings can generate resources such as food and iron; towns/cities can be conquered and colonized… you get the picture.

My initial investigation of the data did not uncover any of the obvious simple patterns, but did manage to find a way of connecting some pairs of players in a transaction relationship (the data for each player included a transaction list which gave one of 255 numeric locations and the transaction amount; I reasoned that the location/amount pair was likely to be unique).

The data is a snapshot in time, which appeared to rule out questions involving changes over time. Finally, I realized that time data was present in the form of the order in which each player created buildings in their village/town/city.

Buildings are the mechanism through which players create resources. What does the data have to say about gamers preferential building construction order? Do different players with different playing strategies use different building construction orders?

A search of the Illyriad website located various beginners’ guides containing various strategy suggestions, depending on player references for action.

Combining the order of the first 20 different buildings, created by all 50,000 players, into an aggregate preference building order we get:

Library
Storehouse
Lumberjack
Clay Pit
Farmyard
Marketplace
Quarry
Iron Mine
Barracks
Consulate
Mage Tower
Paddock
Common Ground
Brewery
Tavern
Spearmaker
Tannery
Book Binder
Flourmill
Architects` Office

A couple of technical points: its impractical to get an exact preference order for more than about 10 players and a Monti Carlo approach is used by RankAggreg and building multiple instance of the same kind of building were treated as a single instance (some form of weighting might be used to handle this behavior):

The order of the top three ranked buildings is very stable, but some of the buildings in lower ranks could switch places with adjacent buildings with little impact on ranking error.

Do better players use different building orders than poor players? The data does not include player ability data as such; it included game ranking (a high ranking might be achieved quickly by a strong player or slowly over a longer period by a weaker player) and various other rankings (some of which could be called sociability).

Does the preference for buildings change as a players’ village becomes a town becomes a city? At over 200 minutes of cpu time per run I have not yet had the time to find out. Here is the R code for you to try out some ideas:

library("plyr")
library("RankAggreg")
 
get_build_order=function(df)
{
# Remove duplicates for now
dup=duplicated(df$building_id)
 
# Ensure there are at least 20
build_order=c(df$building_id[!dup], -1:-20)
return(build_order[1:20])
}
 
# town_id,building_id,build_order_for_town
#1826159E-976D-4743-8AEB-0001281794C2,7,1
build=read.csv("~/illyriad/town_buildings.csv", as.is=TRUE)
 
build_order=daply(build, .(town_id), get_build_order)
 
build_rank=RankAggreg(build_order, 20)

What did other teams discover in the data? My informal walk around on Saturday evening found everybody struggling to find anything interesting to talk about (I missed the presentation on Sunday afternoon, perhaps a nights sleep turned things around for people, we will have to check other blogs for news).

If I was to make one suggestion to the organizers of the next gaming data hackathon (I hope there is one), it would be to arrange to have some domain experts (i.e., people very familiar with playing the games) present.

ps. Thanks to Richard for organizing chicken for the attendee who only eats pizza when truly starving.

Update

Usage statistics for the game DDNET.