Not everyone who reads blogs comments on posts or writes their own blogs.  That should not surprise anyone.  In fact, according to Jackob Nielsen's Participation Inequity: Encouraging More Users to Contribute post from last October, only about 5% of Internet users blog. (Hat tip: Suw Charman)

Nielsen explains that "In most online communities, 90% of users are lurkers who never contribute, 9% of users contribute a little, and 1% of users account for almost all the action." Regardless of the accurateness of such figures, low participation negatively affects any community since the feedback produced by the contributors is likely not representative of all those who use the community. 

For instance, how relevant are user reviews on Amazon when say 12 people review a book that millions bought?  How about the search engines?  If they use links as a major metric of measuring relevance, how good are their result pages since a very small subset of web surfers create links through web pages and blogs?

A recent example of participation inequality side effects is when a Utah school voucher bill was debated on the legislative wiki Politicopia.  Utah State Representative Steve Urquhart — and voucher bill sponsor — launched the wiki earlier this year.  With great fanfare from publications like the Wall Street Journal's sister site Opinion Journal, many observers were excited to see how the debate unfolded around the school voucher bill; it faced an uphill battle since similar bills failed during the last several years.  In fact, activity on school voucher bill page on Politicopia is what many consider the reason for its passage.

Citizens upset that the school voucher bill succeeded — diverting state money from some of the lowest funded schools in the country — successfully collected enough signatures to have a referendum during a special statewide election in November to potentially overrule the legislature and reject the bill.

Although a group of Utah citizens did participate in the school voucher bill debate on Politicopia, the zeal and excitement surrounding the community was misinformed since participants were a small minority of Utahns.  They simply did not accurately represent their fellow citizens.

So, what can one do about participation inequality?  Nielsen says nothing; the best you can do is to increase opportunities and lower barriers to participation.  A lurker rate of 80% is better than 90%.  He gives a few suggestions on how to encourage greater participation.

I would also like to suggest reading Forrester Research's Social Technographics study; in it Charlene Li argues that sites should gradually train people to participate in simpler ways before inviting them to interact in a more complex fashion.  For example, why would a site's audience create and upload videos if its members aren't even willing to post text comments?

UPDATE: (The individual post pages on the blog that the following links point to sometimes appear as "404 Not Found" pages.  If this happens, visit the blog's home page at Suw Charman has some interesting thoughts about on-line participation levels at the Conversation Hub group blog for the Supernova 2007 Conference.  Also at Conversation Hub, Renee Hopkins Callahan argues that "it's considered essential to *frame* a specific challenge around which you want the participants to create ideas. Such an approach will also help keep participation levels up in any kind of social network."