Monday, September 14, 2009

People who are unintentional "spoilers"

I've noticed some interesting cross-player interactions in game win rates. If a player is good at a particular game, or games in general, you'd expect them their performance to be relatively consistent across opponents. Or, you might reasonably expect they do well against most opponents, but not against others, who beat them more often, even if that opponent isn't as good in general. That is, you might see a rock-paper-scissors kind of effect.

But, in at least two cases, I've observed a different phenomenon, where a particular player "S" has a substantial effect on the performance of player "P", without that performance coming at a cost or benefit in S's performance. Here's the two examples I've observed. All games include me as well, so it may be a three-way interaction.

I have a colleague T who we play a lot of Race for the Galaxy with. He is good at it. He has won 20 out of 46 plays, with an average number of players of 4. But, if you break it down further, there's another person "R" who basically is necessary for T's performance to be high:

T's win rate, games with R: 18/33
T's win rate, games without R: 2/13

Further, while R does better when T is not in the game, the effect on his own play is only part of the change in win rates:
R's win rate, games with T: 5/33
R's win rate, games without T: 6/16

In the other example, the effect seems to apply across all games. "E" does very well overall. In 327 games, he's won 94 games with an expected number of wins of 80, given the numbers of players. But, when A plays, E's performance suffers badly, but it doesn't really help A:

E's wins, without A: 87 wins, 69 expected (276 games)
E's wins, with A: 6 actual, 10 expected (51 games)

A's wins, without E: 22 wins, 23 expected (93 games)
A's wins, with E: 10 wins, 10 expected (51 games)

In both cases the help (R) or hindrance (A) seems mostly distribute wins to other players. Since I'm the only other constant player throughout the games:

My wins (E, not A): 65 (69 expected, over 283 games)
My wins (E & A): 17 (10 expected over 51 games)

My wins (T, not R): 6 (3 expected, 13 games)
My wins (T & R): 6 (8 expected, 33 games)

One more example, lest this all sound like sour grapes; the introduction of R or A helps or impedes the other players as well:

Games with T & !R: T wins 15%, neither I nor T wins 38%.
Games with T & R: T wins 55%, neither I nor T wins 27%.
So, R benefits T and impedes everyone else.

(Limiting to 4 player games with E & A so the percentages can be compared)
Games with E & !A: E wins 42%, neither I nor E win 40%
Games with E & A: E wins 0%, neither I nor E win 53%
So, A impedes E and benefits everyone else.

Further, I'm pretty confident in neither of these cases is the spoiler intentionally helping or hurting the other player. That is, R isn't trying to help T, and A isn't targeting E, it just happens that way.

There's lots of plausible mechanisms, psychological, in-game, and otherwise for what's going on here, for which I don't have any compelling data, but it's an interesting phenomenon, or perhaps simply an anomaly.


Sunday, September 13, 2009

Davis Mega Maze via GPS

The Davis Mega Maze is excellent. It is an elaborate multi-acre corn maze, with bridges. It's a great deal of fun. If you're in Massachusetts, it's a worthy excursion each year, with kids, or as just adults. This year it took us over 3 hours to solve the maze.

Except when the battery performance is awful, or the on-device storage is running low I love my Android phone. The apps are fewer than the iPhone, but except for games, I find the Android apps more useful (Gmail, Gtalk, SkyView, Zombie Run, Barcode, Twidroid, WeatherBug, Calendar, etc.). In particular, My Tracks is really cool.

Put them together, and what do you get? An amazingly cool digital memento of this year's solving of the maze:

View Mega Maze in a larger map
In addition to the GPS resolution not being quite good enough to distinguish two paths in the corn that are barely a meter apart, they change the maze with non-corn barriers slightly every day, so it won't quite help you solve it, and it didn't help us that much when we were in the maze (though it did, a little), but it's really cool.

Saturday, April 4, 2009

Google's architecture through the eyes of a 4-year-old

My 4-year-old daughter drew this picture of the Google architecture today (I told her how to spell the words):
Here's the backstory that lead to this picture...

I started working at Google when my daughter was two years old. I would come home from work and I would ask her "What did you do today?" and she'd answer. Before long, she'd start asking me, "What did you do today?" Frequently, in my first year at Google (and still today) the answer was "I wrote a MapReduce." Fast-forward two years, and now both she and my son (age 2) often race to the door when I arrive home to see who can be the first to ask "Daddy, Daddy, did you write a MapReduce?"

She is also fascinated by "how things work" and will regularly request at bedtime an explanation of how something works. "How does the light work?", "How does your stomach work?" etc. Not too surprising for the child of two engineers. As a brief diversion, I had another "I live in the future" moment the other night: My daughter asked at bedtime "How does your eye work?" I explained in as much detail as I could and she was intrigued, and asked "Can we see it?", so I put my eye close to hers and explained what she was seeing. She replied, "No, I mean the inside!". An idea dawned on me. I pulled out my G1, spoke the words "diagram of an eye" (Voice Search is awesome), and a few seconds later a beautiful diagram of an eye was on the screen. My daughter was satisfied, but didn't even blink at what had just happened, while I felt like I was in a remarkably banal Star Trek episode.

In any case, yesterday I arrived home, greeted by the chorus of "Did you write a MapReduce?" to which I replied "Yes, I wrote a MapReduce." She asked what it did, I explained that it organized some information about books in a Bigtable, which is a useful place to store large amounts of information. She declared, "At bedtime tonight, I want you to explain how a Bigtable works." At bedtime, she did in fact ask, and I did my best to explain it at a 4-year-old level and she seemed to absorb it alright. After she went to bed, in a combination of amusement and fatherly pride, I twittered about it.

This morning, I told her that some of my friends were very impressed that she wanted to know about Bigtable. So, she decided she would draw a picture. The picture shows, on the Bigtable side a table (notice the legs) with a bunch of boxes (bigtable cells) organized in rows and columns. On the MapReduce side, the box between "Map" and "Reduce" is the mapper, while the big swirly cloud connected to it is the shuffle phase, and then the nice neat lines connected to that is the reducer. I'd love to say the big scribble at the top is the "cloud" from cloud computing, but she informs me that's the ceiling.

(Actual details about various parts of Google's architecture are available at Google Research's site, including papers on Bigtable and MapReduce.)

Sunday, March 1, 2009

Mozy review: It doesn't work

I tried out the free version of Mozy in the fall of 2007, having heard good things about it. It quickly backed up over a gig of data and I decided to sign up. From here it went bad. I knew the full upload was going to take a while, but based on how it worked during the free period, it looked like it should take 4-8 weeks to back up my 100G of data. It slowed down dramatically, in two senses:
  • The raw upload rate got a lot slower
  • It would regularly get "stuck" and have to be manually killed and restarted, sort of defeating the purpose of the whole background thing.
Further, it would regularly (many hours a day) use 100% of CPU, rendering the machine unusable. Changing the set of things to be backed up would always kick it into this state, and would take hours and hours to finish, meaning there was no easy way I could tweak the backup set to just backup the most important stuff first.

So, I contacted support. They were very friendly and encouraged me to upgrade to the latest and greatest client, which I did. They extended my membership by one month for free. But, none of these upgrades worked. I asked that they cancel my account and they instead kept suggesting I try other things. I tried several of them and nothing worked. At this point, several gigs of data had been backed up, but my machine was still almost unusable while a backup was running. So,
I decided to try a test restore. I went to their web UI, which took tens of minutes to load, and in the end gave me a "No backups found" error or a generic "An error has occurred" message. I again contacted support, and they replied "well, it works for me", which was singularly unuseful. I asked again to cancel, and again got the "well, upgrade to the new version". I gave up. Nine months later, the 100% CPU problems were still occurring, though with less frequency,
and it finally "finished" the backup. I tried another test restore, and it still didn't work. I gave up and turned off Mozy.

(A couple other things worthy of note: This was all on a MacBook Pro, and I lived in two different places during this time, with very vanilla network configuration, using two different ISPs, so I'm doubtful the problems were particular to my situation)

Then, this past fall, I got auto-renewed. I sent an email making it clear I wanted my money refunded and my service canceled in no uncertain terms. I canceled and they refunded all but $5 of my renewal fee. So, in the end:
  • The software was slow to the point of being unusable.
  • The software had a detrimental effect on my usual use of my machine
  • The restore functionality never worked
  • Despite multiple requests, they refused to cancel my account in the first place
  • On cancellation, they didn't even refund the full charge

Sunday, February 8, 2009

Recent sci-fi reading

Over on Chris Shabsin's blog he posted his sci-fi reading list and I posted some comments (I've read just under half of his list, and I should harvest the remainder of). I thought I'd repeat some of those comments here and expand on them a bit.

Last year, I raved about Spin and thought Axis was pretty good, and this year I finally got around to reading some more Robert Charles Wilson. So far this year I've read Darwinia, Blind Lake, and The Harvest. None were as good as Spin, but all were good, and I especially liked Darwinia.

Other sci-fi authors I'd recommend:
  • Kurt Vonnegut (Cat's Cradle and Slaughterhouse Five, in particular, but the latter is barely sci-fi)
  • Stanislaw Lem (Cyberiad and The Futurological Congress were favorites when I was a teenager)
  • Timothy Zahn (almost everything)
  • Larry Niven (I remain impressed with how well most of his work has aged)
You can read my full comment on Chris' blog.

I'd also recommend or as good sites for social-networky tracking of reading lists, reviews, recommendations, and read books. I'm currently using goodreads for this. My "read" list is far from complete, and as I think of it, I backfill with authors or books, but it's more about current reading. I'd welcome comments here (or on goodreads) on my current to-read list or new suggestions for additions.

Thursday, January 1, 2009

2008 Games Summary

The larger half of my game collection
Well, after several years of gradual decline in game playing, the trend has finally reversed and I again played over 1 game/day average. Additionally, it was a good year for gaming: we moved and I now have a dedicated game room (pictured), my kids continue to want to play lots of games, and my daughter is now able to play some "real" games, and my colleagues have been totally bitten by the Race for the Galaxy bug. Overall, it's been a good gaming year.

Games Room
We said when we moved we'd make sure the new house had a room that could be the games room. Well, we moved, and we did (see photo) and I played a lot of games there. In the end I played 112 games at home, about 96 of them in the new house. Even better, the games room is front and center in the house, and I look forward to hosting more gaing sessions in 2009.

Gaming with Kids
My kids continue to turn in to excellent gamers. My 4-year-old is now playing games with meaningful choices and my 2-year-old's favorite way to delay bedtime is to ask "One more game?". Further, my 4-year-old was the person I played the most games with in 2008. In 2008, I played 63 games with her.

Gaming at Work
At the end of 2007 I started organizing gaming at lunch at work on Fridays. By mid-2008 we were regularly having two tables of gaming for the hour, and a waiting list for Race. We got a second copy of Race and expanded to Monday lunchtime gaming as well. In the end I played 59 games at lunch and another 29 at other work related events (retreats, after work, etc.) The majority of the work gaming has been Race, but with a solid sprinkling of Dominion, 6 nimmt!, For Sale, Pandemic, and the like.

Regular Gaming Group
I made 17 out of 24(?) sessions this year, and this remains my main source of variety in games and remains a great group to game with.

Overall Stats
  • 370 Games Played
    • 27% at home (family & guests)
    • 24% at work
    • 19% regular gaming group
    • 18% "events" (eg, Unity Games)
    • 12% other friends' homes
  • 168 different Titles
  • 140 days with at least one game played
  • 66 new-to-me games played
  • Gamed with 159 different people
  • 26 new games or expansions acquired
Top Games
  • 80 games of Race for the Galaxy
  • 22 games of Dominion
  • 11 games of Electronic Catchphrase
  • 8 games of Monkey Madness
  • 8 games of Pandemic
  • 6 games of 6 nimmt!
  • 6 games of Arbos
  • 5 games of Walk the Dogs
  • 5 games of Go Away Monster!
  • 5 games of Zack & Pack