First some thank yous. I’ve tried to quote everyone who wanted to be quoted, and to all those who gave me info anonymously, you know who you are and thanks.
The iTunes charts are very important for the Music Industry, but the podcast charts are a Sudoku puzzle wrapped in Rubik’s Cube. Although knowing the formula (or its approximation) wont help you usurp Ricky Gervais or Chris Moyles but it my help you; optimize, maximize and …err caramelize.
My attempts over the last few weeks to reverse engineer the algorithm have exposed 5 areas that I feel are the most important in a successful podcast. The data I have used is a mixture of empirical facts, cold hard statistics (lovingly donated by the some of the top podcasters) and gut feelings on how I’d create a ranking algorithm (having spent years working on ranking systems in a vain attempt to topple AltaVista, Yahoo! and Google, in that order).
I’ve also collected plenty of anecdotal evidence to back up my clams and help me hypotheses about the exact “mix of ether and witchcraft” Apple use.
Subscriptions & Downloads
Everyone I spoke to agreed the most important element in climbing up the charts in iTunes are subscription. However this is where the consensus ended, some place almost all their faith in subscriptions others plumbed for a weighting between subscriptions and downloads.
My personal view is it more likely to be a weighting, I’ve heard suggestion of 60:40 to 80:20 in favor of subscriptions. This means for every subscription, you have to get between 60-80 downloads to match it. I like this model because it awards consistent podcasts and those with a large subscribed base.
My evidence for this can been seen for yourself, you’ll notice an increase in chart position for podcasts that have just released a new show. With popular podcasts this might only translate into a place or two, and for podcasts in the top 10 the effect may not even be visible, but if you look towards the bottom of the cart you notice a lot more movement.
Of course this has it issues, and has lead to the Gervais Effect (I just made that up) this is where a podcast, such as Ricky Gervais’, has a massive subscribed base and a 5 minute podcast every 6 weeks is enough to keep him in the top 10.
Plays
During the investigation I heard a rumour that “plays” we used as a metric. I am 99.99999% sure this in not true, for a start people would know if Apple were eves dropping on your listening habits plus it would require Apple to download every podcast and analyze it to determine it uniqueness (and for iTunes to also do this). I don’t want to get too technical but, rest assured Apple don’t track you listening habits (unless you use the Genius feature.)
Reviews & Editorial
This is the most contentious area. Nobody was willing to speak, “on the record ” but I did dig up some great nuggets of information. Apple (as you would expect) likes to keep a tight control on all aspects of their business, iTunes is no exception and neither are the charts. Apple has a full veto over any and all podcasts but also can apply some of it own weighing, both positively and negatively. This is most noticeable with the BBC podcasts. They regularly defy the normal downloads rules and post higher chart entries than “independent” podcasts.
While reviews on their own won’t get you higher in the charts they will get you in “New and Notable” and possible as a “Featured” podcast. I am reliably informed if you make it as a ”Featured” podcast you’ll be contacted by Apple and if they like you, maybe even buy you lunch.
Video vs Audio
This only comes into play in the combined charts. A simple glance at that chart will tell you, its about a 50:50 split. But there is further evidence Apple prefer to push video over audio.
The iTunes Clepsydra
1. Subscriptions and Downloads (possibly reviews and ratings).
2. Read off your rank and compare with other Podcasts to determined chart position. Apple favored Podcasts (BBC et al.) might have a different scale, thus artificially inflating their position.
3. Old subscriptions and downloads “drip” away, this method favors regular podcasts with large subscription base.
4. Archived download data, possibly used to determine ”Featured” and “New and Notable” podcasts.
Improvements
Working for bands, I would often bump up against the UK Chart Company Rules [PDF] a vast and seemingly random collection for things you can and can’t do when releasing a single. Things like track length, price etc.
Having researched the iTunes chart I can now see why these rules are necessary. Is it fair that The Onion at < 1 minute (but daily) be ranked along side something like Answer Me This, weekly and 30x longer? How about Ricky Gervais, intermittent and only ever adverts or recycled material. Compare this to Stephen Fry, again intermittent but superbly produced and always original.
One thing is clear Apple needs better filtering, to enable user to find new stuff. It should publish downloads stats and allow podcast producers to access analytics on their shows. Finally a podcast that has not been updated in the last 3 months should not feature in the top 100, this would churn the chart and allow fresh content to reach new audiences.
Apple has a wealth original content (some of it much better than the latest teen drama form ABC) that it largely ignores, it could better market it and help monetize content, but that my friends is a topic for another blog post.
Thanks to Scott and Matt from the Guardian for you invaluable insights.