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Is the iPod Shuffle Playing Favorites?

marksilverman writes "Steven Levy at Newsweek is reporting that his iPod Shuffle seems to favor certain songs. Is Apple receiving kickbacks to promote certain artists? Apple denies it, of course, and Levy had the good sense to ask a mathmatician and a cryptographer who explained that it's probably just humans finding patterns where there are none." Less neurotically, both CNet and PCWorld have discussions of the Shuffle's interior spaces.

61 of 524 comments (clear)

  1. Now that you mention it... by Anonymous Coward · · Score: 5, Funny

    I have heard YMCA an inordinate amount of times on my ipod shuffle. I wonder what that means.

    1. Re:Now that you mention it... by Anonymous Coward · · Score: 5, Funny

      Maybe you should download more than 1 song into it.

    2. Re:Now that you mention it... by imag0 · · Score: 4, Funny

      I have heard YMCA an inordinate amount of times on my ipod shuffle. I wonder what that means.

      Means you need to steal better music, of course ;)

    3. Re:Now that you mention it... by nihilistcanada · · Score: 5, Funny

      You should join the NAVY?

    4. Re:Now that you mention it... by MacGod · · Score: 5, Funny

      I have heard YMCA an inordinate amount of times on my ipod shuffle. I wonder what that means.

      Well, let's just say my response is likely to end with "not that there's anything wrong with that"

      --
      "Reality is merely an illusion, albeit a very persistent one " -Albert Einstein
    5. Re:Now that you mention it... by plover · · Score: 4, Funny

      Your iPod thinks it's a TiVo?

      --
      John
    6. Re:Now that you mention it... by NanoGator · · Score: 5, Funny

      "I have heard YMCA an inordinate amount of times on my ipod shuffle."

      That's no need to feel down.

      --
      "Derp de derp."
    7. Re:Now that you mention it... by Paul+Lamere · · Score: 4, Funny

      I only have one song on my iPod too. It's by Led Zeppelin. When I hit shuffle play the song remains the same.

  2. humans are wired to... by jxyama · · Score: 4, Interesting

    ...look for patterns, to at least internally provide an explanation. (whether it's true or accurate is irrelevant.) go to craps table - unless you are neurotic, everyone develops a pattern to how they roll the dice. no reasons, no explanations. we are just made to take emotional comfort in attributing some pattern, real or otherwise.

    1. Re:humans are wired to... by fafalone · · Score: 5, Interesting

      We actually talked about this in my statistics class today. The professor actually had a friend who could flip a coin and get it to land on whatever he wanted, virtually every time. Made alot of money hustling people with that. It is possible to develop patterns of manipulating 'random' events, through skill of hand (or programming skill), that to most people still look like they're obeying pure randomness, but are actually being subtly manipulated behind the scenes. There's no doubt in my mind it's a possibility that Apple is trying to walk that line.

    2. Re:humans are wired to... by Rei · · Score: 5, Interesting

      Or it could be an accident. For example, picture this code:

      const int song_id=random()%num_songs;

      At a first glance, that might look reasonable; however, once you start to get a lot of songs (and you start to approach RAND_MAX), it will skew your result in favor of low-ID songs.

      Who knows if anything is going on here, though.

      --
      Don't take a knife to a gunfight, or even a knife to a knife fight. Take a gun to a knife fight.
    3. Re:humans are wired to... by yali · · Score: 5, Interesting

      This page has more information about this phenomenon, called the clustering illusion. Another manifestation is streak scoring in sports, a.k.a. the hot hand in basketball. Players are often though to be "on a roll" when in fact their larger scoring pattern fits a random distribution around a mean.

    4. Re:humans are wired to... by wfberg · · Score: 5, Insightful

      This absolutely right. Also, using this method, inevitably some songs will occur multiple times in the playlist, since you're not keeping track of dupes (much like slashdot).

      If you need to randomize an array, the easiest way to do it is to assign each item a random number, and then sort the array using the random numbers as a key. That way every item occurs only once in the randomized list.

      You still need a decent pseudo random number generator of course, if you're using a pseudo random number generator that only produces 5 discrete values and repeats them over and over it doesn't help much.

      On the other hand, for an application like a playlist shuffle, you don't need a cryptographically secure RNG, just a PRNG (such as a Mersenne Twister), that uses the current time in milliseconds as a seed would do nicely.

      --
      SCO employee? Check out the bounty
    5. Re:humans are wired to... by Zorilla · · Score: 5, Interesting

      This is got to be a result of the random number generator. Winamp and XMMS are exactly the same in this regard. When my music collection got big enough, I usually just put the player into shuffle mode. It always seems to pick the same songs over and over. Of course, the results are slightly different in XMMS as compared to Winamp.

      Of course, I just opened Winamp to test this out and it knows I'm blabbing about it and it's playing music I have not heard in a while.

      --

      It would be cool if it didn't suck.
    6. Re:humans are wired to... by Basehart · · Score: 3, Funny

      OK, that does it. I'm going to buy an iPod Shuffle tomorrow.

    7. Re:humans are wired to... by displaced80 · · Score: 4, Interesting

      ... and this is exactly what iTunes and the iPod/iPod mini seem to do (no idea about the shuffle).

      Hit Play when shuffle's enabled, and it will shuffle the playlist before commencing playback. You're guaranteed not to get repeats until the playlist loops. The other benefit is that you can skip forward and back through the shuffled playlist normally. Mine often randomly picks 4 or 5 songs in a row that go well together, so I'm able to skip back and listen to those in that order when I like.

      --
      What's the frequency, Kenneth?
    8. Re:humans are wired to... by Motherfucking+Shit · · Score: 4, Interesting
      This page [skepdic.com] has more information about this phenomenon, called the clustering illusion.
      Thanks for that link. It's a good explanation of something one of my college professors said, which has stuck with me ever since: "A random number generator isn't truly random unless it can potentially generate the same number many times in a row." The idea being that if an RNG was programmed to avoid producing the same number repeatedly, it wasn't really generating random output.

      The "clustering illusion" (I never knew there was a name for it) has some interesting applications in real life. Dice in a casino is probably the most obvious example, but things get more interesting as the field gets lower; like, say, 1 and 0. This example applies decently to MMORPGs, where things like whether or not you strike your foe, or whether or not you gain in a skill, are based on your skill times some sort of random number. I was a hardcore addict of Ultima Online for a few years, and one of the common complaints was "I have a skill level of X, but I failed to land a hit on my opponent Y times in a row, something is wrong!"

      I guess the next time my UO addiction recurs, I'll have a valid explanation for that phenomenon.

      (Would have posted this about 3 hours ago, but Slashdot went down, or something, and I lost my original comment. Had to rewrite from memory.)
      --
      "BSD: Free as in speech. Linux: Free as in beer. Windows 10: Free as in herpes." --Man On Pink Corner in #52607549.
  3. If... by Walker2323 · · Score: 5, Funny

    If i Hear Fiona APPLE one more time, I'll kill myself.

  4. Well... by Anonymous Coward · · Score: 5, Funny

    Levy had the good sense to ask a mathmatician and a cryptographer who explained that it's probably just humans finding patterns where there are none.

    Didn't stop him from submitting it to Slashdot though. No facts? Great, put it on the front page!

    1. Re:Well... by JPriest · · Score: 5, Insightful

      I think the point of the story is not just to report "news" but open up the topic for discussion. I am sure making the front page will cause at least a few more people to investigate the claim, or at the least monitor the behavior more closely of their shuffle.

      --
      Saying Java is nice because it works on all OS's is like saying that anal sex is nice because it works on all genders.
    2. Re:Well... by AvantLegion · · Score: 5, Funny
      Didn't stop him from submitting it to Slashdot though. No facts? Great, put it on the front page!

      Hey, shut up! It's a new post and it's NOT a dupe. Let's not push our luck, OK?

  5. enough! by kajoob · · Score: 5, Insightful

    From the article:


    I explained this phenomenon to Temple University prof John Allen Paulos, an expert in applying mathematical theory to everyday life. His conclusion: it's entirely possible that nothing at all is amiss with the shuffle function


    The slashdot article??


    Is the iPod Shuffle Playing Favorites?



    and



    Apple denies it, of course



    Enough with the inflammatory headlines!

    --
    Quidquid latine dictum sit, altum viditur
  6. Bullshit. by mooniejohnson · · Score: 4, Insightful
    What paranoid bullshit. That would mean that they'd be releasing firmware updates every couple of weeks to update the list of "preferred" artists, and then it would have to scan through your tags and make a neat little catalog so it knows who to play. Doesn't that seem rather pointless? Besides, if it plays the artists, haven't you already paid for them? Who would buy into kickbacks for more people to listen to their songs? Just tune in a radio station! They play repeats all the time! Honestly, some people.

    This post brought to you by Teenage Angst and Caffeine!

    --

    Elmo knows where you live!

    1. Re:Bullshit. by smartsaga · · Score: 4, Insightful

      I guess all you need is a little bit that indicates whether the song is "favored" or not to be played more than the others... So no need to update firmware every few weeks because the songs would already have a value that determines the level in which they should be favored in the "not-so-random" shuffle playback.

      I know I am being simplistic but that is the way I would do it.

      Your shuffle are belong to us... get it?

      Have a good one.

      --
      ===== "Every head is a different world so don't invade mine you FREAK!" smartSAGA said
  7. Dude, I've seen this article before. by ABeowulfCluster · · Score: 5, Funny

    I think slashdot favours certain articles and repeats them over and over again.

  8. Ipod - The little white box of prophecy by bildungsroman_yorick · · Score: 5, Funny

    Clearly we need to lock an ipod in a room with the same scientists who discovered revolutionary psychic patterns in that little black box a couple of weeks back on slashdot.

    Perhaps Ipod will predict when Hewy Lewis and the news will make a mainstream comeback?

  9. Nail on the head! by MrPerfekt · · Score: 5, Funny

    You're absolutely right!@ There's an array inside the iPod shuffle of about 150 artists that will take precedence over all other artists and will play songs by those artists 3 times more than all others because because Apple recieved $100,000 per to make it happen.

    Those of you that think that sounds completely plausable, please step to the left. Everyone else please step to the right.

    Everyone standing on the left, please drink the magic juice we're distributing because you've been selected to come with us to the great beyond where you will experience another plane of being.

    Everyone on the right, enjoy the rest of your life because you enjoy logic and reason.

    --
    I just wasted your mod points! HA!
    1. Re:Nail on the head! by Ghostgate · · Score: 5, Funny

      Hmm. At first, I was headed over to the right. But your offer of magic juice on the left intrigues me.

    2. Re:Nail on the head! by prockcore · · Score: 4, Insightful

      Those of you that think that sounds completely plausable, please step to the left.

      Look up the word "payola" if you think that record execs wouldn't do this.

      It doesn't need to be in the shuffle. It could be part of the AutoFill in iTunes.

      Do I think it's really happening? Not really. Do I think it's plausible? Yeah... experience with radio tells me that record companies would do this if Apple let them.. and who is Apple to turn down money?

    3. Re:Nail on the head! by The+One+and+Only · · Score: 4, Funny

      Do you wish to subscribe to the magic juice newsletter?

      --
      In Repressive Burma, it's not just your connection that dies. slashdot.org/comments.pl?sid=314547&cid=20819199
  10. Obligatory random != pseudo random by MasterC · · Score: 5, Informative

    Computers can't generate true random numbers (ok, at least I don't know of any current methods) but only pseudo random numbers. There's a precise mathematical description that gets you from one number to the next.

    Who knows, maybe Apple uses the meta data for a song to determine the random order (anyone hack it yet and finding the algo?) and some people just get "lucky" like prof John Allen Paulos explained in the article. You might happen to flip 6 heads in a row (despite being a 1 in 64 chance of it happening) and you might get 6 songs from an artist in a row.

    Sounds to me that it's a conspiracy theory at best.

    --
    :wq
    1. Re:Obligatory random != pseudo random by James_G · · Score: 4, Informative
      Computers can't generate true random numbers (ok, at least I don't know of any current methods) but only pseudo random numbers

      Intel has been including hardware RNGs in their chipsets for a while now. Apparently, this is a truly quantum random number generator, although that could be so much marketing material. A quick Google doesn't turn up any obvious pages disputing this, although I didn't look too hard. Wikipedia has more info.

    2. Re:Obligatory random != pseudo random by Percy_Blakeney · · Score: 3, Interesting

      I just can't resist adding one of my favorite computer science quotes from von Neumann:

      Anyone who considers arithmetical methods of producing random digits is, of course, in a state of sin.

    3. Re:Obligatory random != pseudo random by SpeedBump0619 · · Score: 5, Informative

      Computers can't generate true random numbers...

      Right, but wrong.

      A pure computational method for generating randomness has not been found...and I'd guess it can't be done.

      However, there are a vast number of randomly timed things that happen in a computer. Your mouse movements have some level of randomness, the time between key strokes on your keyboard, etc.

      There are ways to harness events which contain levels of randomness and use them to generate truly random numbers. I highly doubt that the ipod firmware really does this...since there are plenty of "random enough" algorithms for such a purpose.

      I'll just bet you really wanted to know that too.

    4. Re:Obligatory random != pseudo random by agurkan · · Score: 3, Informative

      No. There is no law of physics that determine when a radioactive decay occurs. Actually everything we know indicates a law cannot be formulated to determine that point in time, since it is not a well posed question. In other words, there is no way for us to determine this point in time, because it is not an observable (in the quantum mechanical sense).

      --
      ato
  11. anti-spoken word by Noksagt · · Score: 4, Informative

    If you have any audiobook or spoken word that have proper metadata, they will never be selected in shuffle mode. While this can be handy for not falling onto a 20 minute chapter of a book randomly, it also makes it a bit more difficult to create cut-ups, or experiment with random spoken words when you want to: you must retag the tracks.

    This is also useful to take long tracks out of random selection. A friend retagged Pink Floyd's 23 minute long 'Echos' as a book after getting pissed off that his Shuffle always seemed to select it.

    1. Re:anti-spoken word by igrp · · Score: 4, Interesting
      Or, alternatively, he could do what I do: use iTunes' smart playlist feature.

      That way, you have a lot more control over what songs get selected and - to tell you the truth - it's a lot more flexible than the autofill feature (it's sort of like discovering perl for the first time -- yeah, it's a lot more clumsy than just whipping up a simple shell script but it's also so much more powerful).

      Basically, what I have a bunch of custom smart playlists. The first randomly selects songs that are :

      • longer than 1:20
      • not comedy, spoken word or audio books (I enjoy listening to George Carlin's rants as much as the next guy but I really don't need to listen to them when I'm out running)
      • not longer than 8:00 (this excludes all jam songs etc.)
      • hasn't been played in three days (to keep things fresh)
      • are not named intro, interlude or skit (for obvious reasons), plus some very custom stuff.
      Then I have a second smart playlist select some my favorite songs that I haven't listened to in a while (5 days).

      I use the 1st playlist to fill my Shuffle up to 75% capacity. The second playlist gets to use the remaining 25%.

      You know, I used to think of all these software jukeboxes as bloatware. And whilst iTunes is undoubtedly quite demanding ressource-wise, I really believe it's well worth it. It's powerful and fun to use at the same time.

  12. Terrible Summary... by IKnwThePiecesFt · · Score: 5, Insightful

    The summary suggest that Apple may be playing favorites, citing an article that concludes pretty definitely that they are not...

  13. Reminds me of another discussion... by MyDixieWrecked · · Score: 4, Interesting

    On macslash.org, there was an Ask MacSlash about iTunes somehow figuring out what songs sounded good together using some crazy sonic algorithm. The guy was asking if it was plausible that iTunes analyzed the songs in the playlist to spit out the best mix possible.

    The basic consensus in the discussion was either "dude, your entire playlist is songs you like, of course it's gonna be a good mix.," or, the option mentioned above about humans looking for patterns.

    Although, throughout my history of having large (over 1000 song) playlists, I've found that no matter what mp3 player I used (hardware, software, or otherwise), there always seemed to be certain bands or artists that would get play more often. I've had weeks at a time where I'd hear Snoop Dogg's Lodi Dodi, Iron Maiden's Quest for Fire or In Flames' Clayman nearly every time I picked up my iPod

    --



    ...spike
    Ewwwwww, coconut...
  14. It's the nonpareil effect by Jeremi · · Score: 5, Informative
    I think what people are seeing is an example of the "nonpareil effect", named after the tasty little candies. The candies were typically colored either red or green, mixed together, and then stored in glass jars.


    When looking at the candies through the side of the glass jar, the first thing you notice is that the distribution of red and green candies doesn't look evenly distributed at all. Instead, there are lots of areas where many red candies are adjacent, and lots of areas where many green candies are adjacent.


    For a long time, many people thought there must be some kind of static electrical effect present that was causing candies of the same color to tend to stick together. Eventually, however, some statisticians did the math and found that there was no such effect at play -- in a completely random system, such "blobs" of like colors are inevitable. Indeed, a jar of candy with no such blobs would be a bit suspect -- what are the chances of the red and green candies always pairing up so that no groupings occur?


    To put it another way: it's all in your heads, guys.

    --


    I don't care if it's 90,000 hectares. That lake was not my doing.
  15. Slow news night? by bonch · · Score: 4, Insightful

    Seriously. There have got to be better submissions in the queue than, "I think my iPod shuffle is preferring certain songs over others. It's a conspiracy!" Come on.

  16. Obligatory Familly Guy Quote.... by aprilsound · · Score: 4, Funny

    "And Tonight at 6, can bees think?
    A new study reveals that, no they cannot."

  17. Dilbert by GyroGecko · · Score: 5, Funny

    Reminds me of a Dilbert comic:

    Accounting Troll: "Over here we have our random number generator"

    Number Generator Troll: "Nine Nine Nine Nine Nine Nine"

    Dilbert: "Are you sure that's random?"

    Accounting Troll: "That's the problem with randomness: you can never be sure"

  18. Make your own by Orinthe · · Score: 3, Funny

    With a little bit of Logic and Reason, you could make your own music.

    Then, you can offer apple $100,000.00 and see if they'll add you to their magic artist array!

    Of course, you might have to pay out to the other artists on it, too, since you'd be decreasing their play frequency by 2/3 of a percent...

    --
    SELECT quote.text AS sig FROM quote NATURAL JOIN attribute WHERE attribute.description = 'witty';
    0 rows returned
  19. A Modest Proposal by hamsterspeed · · Score: 3, Funny

    If i Hear Fiona APPLE one more time, I'll kill myself.

    Perhaps you could remove it from your iPod Shuffle loadout?

    --
    pants
  20. Re:Probably... by simon_c_heath · · Score: 4, Insightful

    Not at all - as was explained in TFA, these are the sorts of patterns you would expect to see with a normal RNG. People may actually be happier with a more complicated shuffle algorithm for shuffling which which ensured that, for example, songs on the same album did not occur too close together. AFAIK, a song will not repeat until all the songs in the device have been played through. However, when people re-shuffle the order this property is lost, so another desirable property might be to keep the last playing time of each song across shuffles and adjusting the order appropriately. If this is done, however, over time the order will be more and more constrained by what has gone before so after all that it is probably better, and definitely simpler, to just shuffle randomly without trying to do anything more complicated...

  21. [meta/ot] Us, the editors by trs9000 · · Score: 4, Insightful

    So, I know its us the loyal readership that is supposed to do the editing essentially (which makes me think we should have a moderation-style system for voting on which stories in the queue should go live (editors, you reading this?!!) but hey!) but when our favorite web tool has spell-checking built in, and you can search up to 32 words at a time.... I mean you might as well just cut and paste.

    What's really interesting, that even though this is a geek site, we can't even get mathematician right. Even more silly is if you check the link above from google, you'll see that the first two results (of 3) are also from right here at the dot.

    All I'm saying is: if it's power to the nerd masses, let's do it. Many posts so far are already complaining about the story. Not to mention it's from MSNBC. Not to mention I've already read it, because it's from almost four weeks ago.

    I realize I am off-topic and complaining, but I wanted to see if we couldn't get a discussion going about a smarter, more democratic way to elect submissions to go live.

  22. shuffling is not as easy as it sounds by martin-boundary · · Score: 4, Interesting
    Instead of asking some random mathematician, the journalist should have asked and expert in shuffling. It's entirely possible that Apple's engineers believe they are producing random orderings without actually doing so. For example, Persi Diaconis showed that you need 7 riffle shuffles to randomize a pack of cards. Other possibilities include the fact that the simplest random number generators such as rand() are utter shit.

    So before dismissing thousands of people, I'd entertain the idea that Apple's engineers simply stuffed up. It wouldn't be the first bug that slips through QA testing.

  23. Random order versus random selection? by mc6809e · · Score: 4, Interesting

    This reminds me of the birthday paradox:

    "The birthday paradox states that if there are 23 people in a room then there is a slightly more than 50:50 chance that at least two of them will have the same birthday. For 60 or more people, the probability is greater than 99%. This is not a paradox in the sense of it leading to a logical contradiction; it is a paradox in the sense that it is a mathematical truth that contradicts common intuition. Most people estimate that the chance is much lower than 50:50."

    Applied here, suppose you have 365 songs. How many random selections must be played before you have about a 50:50 chance of hearing a repeat? Just 23 songs.

    What most people want is not random selection, but random order.

  24. Re:Probably... by mccalli · · Score: 4, Informative
    I'm the author of StartupFrills, a now-ancient Mac utility to do various things at boot time. Amongst other things, it shows a random startup screen.

    I noticed that screens towards the top end of the scale seemed to show up more than screens towards the bottom (ie. if you had twenty images, images one to ten would should up more than eleven to twenty). I did some sort of multipass algorithm to stop this happening - I forget exactly what I did now and the source is lost, but I definitely had to change things to make it acceptable.

    Cheers,
    Ian

  25. my iPod shuffle tends to play more from 2 bands. by very · · Score: 3, Funny

    I noticed that too.
    I have a 1GB iPod shuffle, currently it contains roughly 100 songs.

    My iPod shuffle "prefers" playing BAD RELIGION and SLAYER.
    I don't know how or why.

    Maybe you guys can help me figure this out.

    here's the breakdown:

    100 tracks (roughly)
    40 BAD RELIGION's song
    40 SLAYER's song
    20 of other bands

    THIS IS REALLY FRUSTRATING that the iPod shuffle prefers playing SLAYER and BAD RELIGION.

    HELP!!!!!!!

    (***casm mode ends)

  26. Slashdot Shuffle by prurientknave · · Score: 5, Funny

    Maybe the editors have a *go with me on this*

    Slashdot Shuffle (TM) system for the articles they post.

    It would explain the dupes and the lack of quality control with one theory. :-D

    I keed, I keed

  27. Re:From TFA: Apple's profit margin by Ohreally_factor · · Score: 4, Insightful

    Think of it this way:

    By supporting Apple, you're also supporting R & D for much of the entire personal computing industry.

    --
    It's not offtopic, dumbass. It's orthogonal.
  28. Shuffling and randomness by shadowmatter · · Score: 5, Interesting

    First, there is the possibility that Apple screwed up the shuffling algorithm -- although not entirely likely. If you ask an introductory programmer to write some code to shuffle an array, you'll most likely get something like this:

    for i in range(array_length):
    j = random() % array_length
    temp = array[i]
    array[i] = array[j]
    array[j] = temp

    This code does NOT produce all permutations with equal probability! Instead, you must use the following code:

    for i in range(array_length):
    j = i + (random() % (array_length - i))
    temp = array[i]
    array[i] = array[j]
    array[j] = temp
    }

    This was cribbed from c2 -- see the full article text here for a more informative discussion.

    Second, I see a lot of people saying "I have a 20GB iPod -- and I swear sometimes it just NEVER plays this one song." Okay, let's assume that a 20GB iPod holds 5000 mp3 files. What's the probability that you play 5000 songs in shuffle mode, and never hear a particular song?

    It's the probability that 5000 times in a row, you hear some other song -- that is, one of the 4999 other songs. Calculating, we get:

    (4999/5000)^5000 = 0.3678.

    So we have a 36% probability of this happening -- which is not a negligible amount! This will further be compounded by two things: First, you have no way of recalling exactly it has been since you heard a particular song -- if your favorite song was played 1000 songs earlier, it probably feels like 2000. If it feels like 2000, it's probably 4000. Because it's a favorite song, your mind will exaggerate the amount. It's like if you crave nicotine, it can feel like days since you've had a cigarette when it's only been hours. Second, you probably have a lot of songs you would call a "favorite" -- with each having a 36% chance of not being played over the course of 5000 plays, your mind will probably register that at least one of them is "feeling neglected."

    Probability is a strange and beautiful thing. Don't expect your average audiophile to understand it. (And I'm not claiming to understand it either, beyond a very cursory level.)

    - shadowmatter

    1. Re:Shuffling and randomness by shadowmatter · · Score: 4, Interesting


      It's the probability that 5000 times in a row, you hear some other song -- that is, one of the 4999 other songs. Calculating, we get:

      (4999/5000)^5000 = 0.3678.


      Almost forgot -- I thought this number looked familiar. Note that as your number of songs approaches infinity, this number approaches 1/e (approx 0.3678, as seen above). Furthermore, this bound is being approached from below:

      (1/2)^2 = 0.25
      (2/3)^3 = 0.296
      (3/4)^4 = 0.316 ...

      So even if you keep ripping or downloading more songs, you're not going to decrease the chance of this phenomenon. Note how likely it is to occur regardless of how many songs you have -- which explains why everyone has probably "experienced" it.

      See, probability really is beautiful ;)

      - shadowmatter

  29. Unscientific by Temporal · · Score: 4, Insightful

    This is not a problem of a bad shuffle algorithm. The problem here is thousands of years old. It is human nature. People see patterns where there are none. People generate theories based on these non-existent patterns. This is how people concluded that the sun orbits the Earth: "Oh, look, the sun looks like it is orbiting the Earth! Therefore it must be!"

    The problem is, if you just put together a playlist with a bunch of artists and play it, it is entirely likely that someone will be played three times in the first hour. And in this guy's case, that someone was Steely Dan. So what does that prove?

    About 500 years ago, we invented something called the "scientific method". Although it is taught to most people in both science and history classes, few seem to understand it.

    The scientific method says that you cannot use past observations to make a conclusion. You must develop a specific test to prove or disprove your hypothesis. You must show before you perform the test that the outcome of the test is relevant to your hypothesis. You can then perform the test and use the results to back your conclusion.

    The scientific method could very easily be applied here. What this guy needs to do is start with the prediction that Steely Dan or whoever will be played three times in the first hour. He must use statistics to compute the probability of this happenning in a purely random shuffle, and should show that the chances are less than 1% (this is a pretty straight-forward use of standard statistical methods). Then he should run the experiment and see what happens.

    My guess? Steely Dan will not play three times in the first hour.

    Without a proper scientific experiment proving this guy's theory, there is no story here.

  30. Statistics can tell you a lot about yourself .... by Gopal.V · · Score: 5, Interesting

    > You're absolutely right!@ There's an array inside the iPod shuffle of about 150 artists that will take precedence over all other artists.

    Back in late 2001, I wrote a simple program which learns which songs I press "Next(b)" before it completes. Finally after 8 weeks, I realized that I listen to
    • Eminem and other rap in the morning
    • Pop music later into the afternoon
    • Rock was for the 5-7 pm slots
    • After 10 , it was usually playing Enigma and instrumentals
    Was quite different on a weekend with no music on saturdays and often slow Elvis songs on sunday afternoons ... I would really love a portable player that understands this and plays accordingly (mpg321 + bash + grep works, but only when I start it properly).
  31. Ob. Simpsons by Zorilla · · Score: 4, Funny

    Yvan eth nioj, baby!

    --

    It would be cool if it didn't suck.
  32. Nice. by Gannoc · · Score: 4, Funny

    Is Apple receiving kickbacks to promote certain artists? Apple denies it, of course.

    Did marksilverman, a slashdot poster, kill a puppy to get an erection? marksilverman denies it, OF COURSE.

  33. Re:I beg to differ! by Glonoinha · · Score: 3, Informative

    Actually I am guessing you hit the nail on the head.

    I was once brought in to fix an application that randomly picked people to pee in a bottle, and a few dozen people complained that they got picked a lot more than other people (out of about 300.) Well it seems that the 'programmer' that coded the app used two digit precision on all math calls (the coder was generally assigned to fiscal apps, two decimal places in money = two decimal places in his head.)

    For those not reading between the lines, a random number returns a real number somewhere between 0 and 1, this real number is then multiplied by the maximum number in your expected range to come up with a random number between 0 and your top number (300 in this instance) but since he was using 2 digits of precision (ie, two digits after the decimal place) all the random function returned was .01, .02, .03, .04, ... .98, .99 and there are only a hundred of those, so there were only 100 possible choices spread across the 300 people on the list, and those 100 choices were coming up a LOT (no surprise there.)

    I figure it has something to do with the random number generator in the baby-iPod.

    --
    Glonoinha the MebiByte Slayer
  34. Re:I beg to differ! by flargleblarg · · Score: 3, Funny

    I was once brought in to fix an application that randomly picked people to pee in a bottle, and...

    Hey, can I get a copy of that code?