Sunday, February 22, 2009

0% Probability

Something cool happened, and the likelihood of it happening was close to zero percent.

On Thursday I attended a Facebook Developer Garage in Palo Alto, which is an event that Facebook puts on to bring its application developer community together. The subject of this particular dev garage was Feeds and Social Distribution, and members of the Facebook Platform team gave developers a sneak preview of where Facebook is headed with the News Feed, and advice on how to create more user-engaging Feed stories. I blogged on the event for Inside Facebook - You can read it here.

Being a Facebook-sponsored event, there was of course a Facebook Event created for the dev garage. I RSVPed "Attending" about a week before the event. A day later, I received a Facebook message from Mike, who was a complete stranger to me at the time.
He wrote: "hi, mind if i ask u a question? have you been to one of these events before? just wondering what it's like and if i should make the trip from SF to go! :)"

I wrote back: "This is my first garage too, so I can't say. Sorry I can't be more helpful!"
That was that.

On the day of the dev garage, doors opened at 6:30 pm, but I got there at 6:00 pm, to find that there was already a long line. The rather unlikely situation was that by a random stroke of luck/timing/coincidence, I was standing in line right behind Mike. According to my rudimentary calculation, the probability of this occurring was:

P = P(Mike messaging Jessica) x P(M & J standing next to each other in line)

There were 622 confirmed guests. Suppose Mike browsed only the first page of results for confirmed guests. There are 10 results per page, and assuming he messaged only one person, P(M messaging J) = 1/10. Say on the day of the actual event, only 50 percent of the confirmed guests show up - 311, then P(M & J standing next to each other in line) = 2/311. That equals:

P = (1/10)(2/311) = 1/1555 = 0.000643

Improbable, huh? Thanks Mike for being my buddy during the event; for explaining some of the more technical concepts to me; and for giving me iPhone tips for beginners. Consider OpenTable (where Mike works) before making your next online restaurant reservation!

10 comments:

james said...

hahaha... let's be a bit more critical here.

what about P(M msg J|J is female)*P(M stands next to J|M is stalker)? arguably quite high. hahahaha....

jkjk. i'm sure the stars are aligning.

the restaurants on open table honestly are a bit out of anyone's budget who doesn't make >$90K. imo. that, or you are a foodie or very irresponsible with money.

james said...

ps, good job with the P(standing next to each other) calculation. i thought it looked off, but verified it, and you were indeed correct!!!

Jessica Lee (Jelly) said...

Thanks for verifying my calculation, and I see you busted out the conditional probabilities. I actually was going to pass my calculation by you first...

As always, I like the way you think, but - trust me - this was a very natural coincidence.

Hm, I'm in the process of learning more about OpenTable. I'll keep your opinion in mind, or perhaps if Mike is reading this thread, he can comment?

Michelle said...

haha jelly, you are hilarious!! i love it :) yeah, i agree with this james person, but i would have to add the condition that J is a cute female. and it's also very possible that M arrived super early, hid out in the bushes, waited til he saw you arrive, and then slipped in line right then.

does the bay area not have restaurant week? i thought that's when most ppl use opentable. i like it, but sometimes, not enough restaurants are on there!

Jessica Lee (Jelly) said...

Hello Michelle! I've always appreciated your imagination. I don't think restaurant week is big in the Bay Area.

Unknown said...

jelly- i just started looking at your blog. i love your posts, inspiration and cute at the same time :)

tshaw said...

my professor is the venture capitalist (or one of them) that invested in open table...he always talks about it in class

mdroz8 said...

hello all--it's mike here :) i'm very entertained at your blog, jessica. thanks!!! i also loved your calculation, but ok, i'll admit, i messages like 2-3 people, but one person was an old coworker of mine, and i'm not stalking you, so the probability is still pretty damn low :)

as for the >90K opentable comment, we're gonna try to change that a bit by offering special deals to entice people to come in and eat quality food for less. i work at opentable and i've even cut back eating at our restaruants. :)

opentable is huge with restaurant week in the bay! i ate at ruth's chris the other day for a great price and got a great 4 course meal for like 35 bucks.

love the blog jessica! and it was fun chatting with u at the conference indeed!

Mickey Sheu said...

This post made my inner nerd smile.

Haha, who am I kidding? This post made me (a nerd) smile =D

Jessica Lee (Jelly) said...

Success! ;) Thanks for stopping by, Mickey.