Pre- and Post-Filters

Chris Anderson's Long Tail blog considers blogs, search engines recommendation technologies and even top-ten lists to be "filters" that help us navigate the new marketplace, "where distribution is cheap and shelf space is plentiful." In the past, Anderson says, producers and retailers served as filters because they had to make careful decisions about what to manufacture and stock on store shelves. Now, though, the role of filter has shifted to the consumer.

Anderson divides filters into two types: Pre-filters, where manufacturers and content creators still have their say, and post-filters, where the consumer rules.

"Rather than predicting taste," Anderson says, "post-filters such as Google measure it. Rather than lumping consumer into pre-determined demographic and psychographic categories, post-filters such as Amazon's custom recommendations treat them like individuals who reveal their likes and dislikes through their behavior. Rather than keeping things off the market, post-filters such as MP3 blogs create a market for things that are already available by stimulating demand for them."

Both pre- and post-filters are hugely important in today's marketplace. But which will become more important in the future? Will post-filters end up being the primary drivers of markets, or will pre-filters reclaim their role as tastemakers?