More iTunes Math

markmcb writes "OmniNerd once again digs into the math behind iTunes. The 5-star ratings in iTunes are actually stored in a variable allowing values from 0 to 100, with 20 = 1-star, 40 = 2-star, etc. Known to few, if you set a rating to 30 (manually), it will show up as 1 1/2 stars in the program's GUI. Matt Schinckel provides interesting statistical evidence showing that not only do non-whole, non-half values (e.g., 47) not increase the amount a song will play, but neither do the half-star ratings (with the exception of .5 star)."

Comments

Future considerations, perhaps?

[CyricZ]

They could have just been leaving their options open for future expansion of the software. Indeed, it would be better for compatibility to already use the 0 to 100 range.

Suppose in the future they added support for giving a song a percentage ranking. It's quite easy to do with the system they're using now. Data from the new software could be used with the old, as the old software is already expecting and can cope with a value in the 0 to 100 range, even if it does so slightly differently than the future versions.

Re:So it's basically fixed point math.

[nathanh]

This story has everything to do with what this site stands for. It directly involves Apple, mathematics, software design, software analysis, software realiability, and so forth.

Indeed, this is a very interesting story that should appeal perfectly to the general Slashdot audience.

The hacker audience who is interested in such things has been dwindling both in numbers and as a percentage. Now the "general Slashdot audience" prefers to fawn over the latest consumer product from Apple, to complain about Microsoft, or to inexpertly argue their "Rights Online".

Articles about technology, impressive hacks, homebrew projects, science and mathematics would be extremely welcome. Unfortunately the editors are infatuated with content-free articles that are little more than advertisements for products like the PS3 and Xbox and iPod.