An interesting observation was put to me in a discussion thread on the Thesis support forum:
[…] when you submit a post with multiple categories, you are creating "duplicate content" which the search engines frown upon.
For example: Let’s use your post "What you can learn from the FT," you have it in your Business, Communication, Mainstream Media, Online Media, Trends categories.
Even though it is the same words on the page, the search engines look at it as duplicate content, and penalize for it. The severity of the penalty is hotly debated, but never the less, you are penalized.
Solution is to only post to your blog with one category, not several.
My response:
I’ve had discussions before over the years re duplicate content on a site, usually referencing cross-posting, ie, duplicating the same content on different sites. I don’t do that with one large-ish exception: the podcast I co-present twice weekly gets posted on the podcast blog and on mine as well as my co-presenter’s. So that’s three places, twice a week.
Then there’s content syndication where some of my content is re-published with my permission by people like WebProNews, BlogBurst and Newstex. (We won’t mention content scrapers who steal your content and post it, too, thus increasing the duplication of your content.)
Now all of that relates to content being duplicated elsewhere, whereas what you’re talking about is the same content on a single site but appearing under multiple categories.
Some people say the differentiation doesn’t matter, it’s all a problem for the blogger with search engines notably Google. Others have entirely different views, saying multiple category assignment is no issue at all.
My own view is that I assign categories to posts that I think will make it easier for people to find that content when they search for it. I see this as common practice even among highly influential blogs. You see the same situation with multiple tags, a slightly different animal than categories.
I’ve yet to see a clearly definitive statement by someone I trust and see others paying attention to that says, categorically, that posting in multiple categories is a fast track to hell!
There’s certainly no consistent opinion that I can find, one way or the other. The closest post I could find is one from March 2007 by Darren Rowse that addresses posting in multiple places rather than posting in multiple categories in the same place.
Incidentally, I find it a bit ironic that, try as I might, I couldn’t think of more than just one category under which to file this post.
So what do you think? Is posting in multiple categories a bad thing?
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I only know WordPress blogs well, but I doubt it’s an issue with any of the major platforms. A catagory listing is only a link to the actual blog post.
The post has a unique URL such as the that for this post: http://www.nevillehobson.com/2009/03/11/is-posting-in-multiple-categories-a-bad-thing/
A category listing is only a link to that URL, it’s not a separate instance of the post. So it’s no different than another site posting a link to your post. In reality it may actually help the SEO of the post because it’s a link pointing to the page. Google discounts links from the same site, but links never hurt unless they are from questionable sites.
IMO,
Chris Kieff
Hobson: Is posting in multiple categories a bad thing?: An interesting observation was put to me in a dis.. http://tinyurl.com/batrfm
@ckieff I see your comment, Chris, thanks. Posted. http://bit.ly/K7Fmh
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I’m running my blogs for my readers and visitors, not for search engines.
In particular on my photoblog a picture will almost certainly fall into several categories. For example a distillery can fall into both the “distillery” and the “Bowmore” category, simply because of what it is (a distillery, of which there are several on the island) and where it is (Bowmore, one of the villages). If I could only use one category then either the person wanting to see all the distilleries would miss it (if I had only given it the category Bowmore) or the person wanting to see all pictures of Bowmore would miss (if I had only given it the category of distilleries).
Therefore I’m staying firmly on the side of the visitor and accept that I might (the emphasis I think is on might) miss on a handful of visitors or a rank or two in the search engines. Those who are really looking for it will find it anyway and my “job” is to make their experience great.
That was my thought, too, Chris: the post is a single entity, as it were, that can be linked to by multiple means. Very different to multiple copies of the same content distributed in different locations.
That’s a good point, Armin, re images. It’s not just about text content.
I think you will like this, from Jakob Nielsen:
“Most weblog software provides a way to categorize postings so users can easily get a list of all postings on a certain topic. Do use categorization, but avoid the common mistake of tagging a posting with almost all of your categories. Be selective. Decide on a few places where a posting most belongs.
“Categories must be sufficiently detailed to lead users to a thoroughly winnowed list of postings. At the same time, they shouldn’t be so detailed that users face a category menu that’s overly long and difficult to scan. Ten to twenty categories are appropriate for structuring many topics.
“On the main page for each category, highlight that category’s evergreens as well as a time line of its most recent postings. ” Weblog Usability: The Top Ten Design Mistakes http://www.useit.com/alertbox/weblogs.html
Thing is, it works for humans so it should work for Google. And if it doesn’t work for Google, then Google isn’t working for humans.