Perseus blog study estimates 31.6 million hosted weblogs

Perseus Development Corporation surveyed ten thousand weblogs on twenty leading weblog hosting services. They conclude 31.6 million weblogs have been created on these top hosted services including 10 million weblogs created in the first three months of 2005.

The numbers

Perseus published some subscriber number estimates as of March 31, 2005 from the major services.

  • 8 million Blogger accounts use Blog*Spot hosting.
  • 6.6 million LiveJournal accounts.
    • 51,900 LiveJournal accounts with syndicated feeds (a free feature).
  • 4.5 million MSN Spaces accounts.
  • 211,500 Bolt accounts blogging.
  • Over 564,000 MySpace accounts blogging.

This survey has a confidence interval of 0.98% for a 95% confidence level.

Interesting numbers. Perseus has a blog survey weblog to respond to questions.

How do you extrapolate a sample of ten thousand to numbers as large as 8 million with such a small confidence interval? There must be more to the study than has been published. I have seen the MSN Spaces and LiveJournal numbers before but the Blog*Spot estimate is new to me.