Spam prevention robots

I have created a blog, and post some group content on it.

And After a week, I have received a mail and said the blog is spam.

It seems that there is a spam-prevention robots doing the detect work.

I really want to know how they judge the spam blog.

Following is some info:

Blogger's spam-prevention robots have detected that your blog has characteristics of a spam blog. (What's a spam blog?) Since you're an actual person reading this, your blog is probably not a spam blog. Automated spam detection is inherently fuzzy, and we sincerely apologize for this false positive.

We received your unlock request on December 9, 2007. On behalf of the robots, we apologize for locking your non-spam blog. Please be patient while we take a look at your blog and verify that it is not spam.

Find out more about how Blogger is fighting spam blogs.