Friday, 16 December 2011

Chances are...

So, walking to work this morning, I selected my "Keep It Down" playlist, and put it on shuffle, even though I sort of wanted to hear the first two songs most. (Background: it's a mix of 42 laid-back songs and is delightful.)

The first song to come on was "Alive" by Edwin, which was the first song on the playlist!!!

What are the freaking chances of that?

(1 in 42)

Ok, not crazy/out-there, but still impressive.

But wait!


The next song was "Angie" by the Rolling Stones. Which is the second song on my playlist.

Ooooo....


Now, people who are good with stats (anyone remember the Destiny Dice?) would say that it's STILL just 1 in 42, but the way I calculate it (hey, MIT, why don't you return my calls?), to play those two songs in that order, the chances are 1 in 1764.

That's pretty freaking awesome.

And then I thought, there's a better chance that maybe I didn't push "shuffle" after all (1 in 2) and perhaps my awe at life, the universe and everything is really because I'm not very bright and/or coordinated in the morning (1 in 2).

The next song came on, by Blue Rodeo.

Oh well, I thought. There goes the incredible what-are-the-odds moment, as the third song on my playlist is "Bad Timing" by Blue Rodeo (is anyone judging me yet?). Which means that there aren't crazy-huge odds. There are only toe fingers.

But wait! It wasn't "Bad Timing"! It was "Five Days in May"!

So, I stand by my 1 in 1764... which is a powerful square number, being 42 x 42... which makes me think there is some meaning to this life after all...

4 comments:

Patti said...

Uhm. I'm not a stats genius, but isn't the probability something more like 1 in 42x41/2 (821) or something since your shuffle would not repeat the same song for the second, thus there are only 41 independent songs... I'm probably wrong ;-)

Anonymous said...

I'm also not a stats genius, but I think Karen was closer. There are 2 possibilities: (a) the shuffle feature selects one of the 42 songs, plays it and returns it to the "pot" from which to choose the next song (leaving the remote possibility of hearing the same song over and over again); (b) the suffle feature selects one of the 42 songs, plays it and discards it, leaving 41 choices for the second song, and guaranteeing that you won't hear the first song again for quite some time.

A - Karen's analysis of 1 chance in 42 x 42 = 1764 is correct.

B - 1 chance in 42 x 41 = 1722 of hearing the songs in that particular order.

C - Or, not only did she NOT hit shuffle, but she also forgot what song #3 in her playlist really is.

- T.

Patti said...

I was thinking of this as more of a lottery question, like getting 2/42 numbers right. I've never had a playlist repeat a song (unless I stupidly put the same song in twice) so I think that's a valid assumption and the lottery analogy a valid one.

http://www.thedatasphere.com/getOdds.html gives me a similar result, for example.

Anonymous said...

OK, the chances of getting the 1st two songs, but NOT the 3rd song? Then, yes, my math is missing some stuff.

I don't think it's exactly like the lottery thing, though, because we have no information on the order of songs 4 through 42... several of them could have matched up.

- T.