How the Netflix Prize Was Won
Wired News (09/22/09) Van Buskirk, Eliot

The secret to the success of BellKor’s Pragmatic Chaos and The Ensemble, first- and second-place winners of the Netflix Prize, was teamwork. The Netflix Prize offered $1 million to the team that could improve its movie recommendation algorithm by 10 percent. Both of the winning teams combined the strengths of several smaller teams that had worked independently before being absorbed by a larger group.

“In combination, these teams could get better and better and better,” says Netflix’s Neil Hunt. BellKor’s Pragmatic Chaos and The Ensemble independently combined their members’ algorithms to design more complex ones that represented everyone’s input.

Rather than appointing a few team leaders that did most of the designing, the teams say they worked communally and thus increased their strength–even if some of the ideas seemed unrelated to the initial problem.

One of the algorithms BellKor’s Pragmatic Chaos used tracked the number of movies a Netflix viewer rated in one day. People who rate a large number of movies at once have most likely seen them a while ago, which affects their judgment. Although this data would not have contributed to the team’s success alone, when combined with other algorithms it increased the group’s performance.

The Big Chaos team, which was incorporated into BellKor’s Pragmatic Chaos, found that users rate movies more negatively or positively depending on the day. By providing an algorithm that took this seemingly irrelevant data into account, Big Chaos helped the winning team succeed. “One of the big lessons was developing diverse models that captured distinct effects, even if they’re very small effects,” says The Ensemble’s Joe Sill.


September 9: dish envy

Sudden, intense longing and regret derived from watching a particularly appetizing dish being delivered to a nearby table, and realizing that one has made an inferior menu selection.

Hank was eagerly anticipating his scallops when the waiter brought the stuffed pork chops to the man at the table next to him. Unable to avert his gaze, Hank began to feel the anguish of dish envy.


 I get this every time I eat in a restaurant.  I’m a poor visualizer and my food is never what I expect.  But everyone else’s is more than I imagined.  I suppose that’s meaningful in some insightful way that I will never understand.  Grass is always greener and all that, perhaps.


September 5: nerd-person

The voice someone uses when explaining something technical or generally nerdy.

I always switch to the nerd-person when discussing the finer points of ewok economics

Order a nerd-person mug — or a mug with any definition — on

This made me laugh this morning.  It instantly reminded me of my friend Mark, the programmer guy, who explains technical things to me until my eyes glaze over, thinking I will understand.  I’m sure I DO get information out of it, but ohmyfuckinggod.   Speaking in the nerd-person, for sure.

So,  if you noticed that I haven’t been around much, it’s because I have my head down and am working 70+ hours a week.  It’s killin’ me.  The powers that be (at my work) are on a rampage to cut costs and casting aspersions upon at least half of the people in the office.  It is very tense,  jobs are going to be lost, mine included.  So much for 20 years of loyalty.  It’s not worth much, apparently.   I think the boss doesn’t think females should do IT because we’re not analytical enough.   Or maybe it’s just me.  I’m not articulate under the best of circumstances and when I get railed at by male authority figures I go into DeerInHeadights mode.  Not a good survival tactic.

An example of how I’ve lost my marbles:   A couple of months ago I had decided it was time to upgrade the blackberries for staff while we still had some budget.  The new iPhones were coming out and everyone was excited,  but realistically, their battery life sucks.  We were standardized on blackberries and everyone already knows how to use them so that’s what my plans were, new blackberries.   But the big boss, that male authority figure, never talks to me and he likes gadgets, so I thought I would engage him with a little debate and get some input from him about whether we should get blackberries or iPhones.  We went back and forth and I argued for the iPhones just for fun.   He wanted me to present a business case for them (why did I start this? yes, I am insane) which was more or less impossible because it’s a fairly bad idea.  He threw all of this in my face during our “meeting” about my job telling me I was not analytical and we should not run IT based on my “feelings”.   Could I explain any of what I just wrote here to him?  No.  DeerInHeadlights mode.  I sat there and took it for 90 minutes.  I didn’t cry, which was apparently a big disappointment for him.   He kept saying things like “Don’t take it personally, but are you even equipped to do your job? I’m going to get someone in here to see if you can really do your job.”  Sweet jeebus, I BUILT that job.  We had 3 un-networked PCs when I started there.

A lot of what is going on seems to be office politics, and the rest is the boss being on a diet and having hunger rage.  It’s scary having your future in hands like that and not being able to do much about it.   There’s more to it, of course, and the bottom line is always money, but it’s certainly been painful for the last few weeks.  I’ve now got a repetitive stress injury in my mouse arm called ulnar nerve compression (I think) and the fix is to not use it until it’s better.  That’s not really an option, of course.  But I haven’t been going online for fun.  😦 I miss you guys.

Anyway, Bob’s got me on his health insurance so if I do get canned there will be that.  I don’t have a degree and no current credentials, my bad for being complacent and learning things on my own.  It’s a tough job market out there and I don’t suppose I can compete.   Look, I’ve already given up before I’ve started!

I guess I can always go wash dishes somewhere.    Feh.