With many marketers placing more weight on the SEO aspect of Internet marketing, I’ve decided it would be nice to do some SEO case studies. I am working on building a niche site for a follow-along SEO study as well.

For this study, I looked at the results of various keywords and analyzed the Google PageRank (PR) of each result, looking to find any correlation between where a site ranks in Google and the PageRank the site has.

Analyzing Google SERP Rank vs. Google PageRank

Many marketers explain that building a long-term income stream is more plausible with SEO than PPC, PPV, or any other paid traffic source. While the jury is still out on that one, building authority (or seemingly authority) sites usually have a lot of potential to hold high SERP (search engine results page) ranks for a long period of time when done correctly.

In my experience, the number of people focusing on and discussing PageRank has been trending down for the past 2 years, and this study may hold a little information as to why people are less worried about what their site PR is.

The Study

I looked at 20 different keywords, broad search results ranging from 5 million 3.5 billion.

I analyzed 2 different groups: 10 keywords with less than 100 million results, and 10 keywords with more than 100 million results.

I analyzed the top 10 results for each keyword for a total of 200 pages.

I included WikiPedia, Amazon, Google News, and Google Images in the results if they did occupy a specific rank spot.

I did not include local results, although they do in fact occupy various SERP spots.

The Keywords

Here are the keywords and corresponding results. Thanks to @gcarivey and @layeredseo for their keyword suggestions.

Under 100M (Low Group):

  • identity management: 5M
  • coffee cup: 13M
  • leather boots: 15M
  • chandelier: 19M
  • mortgage rates: 25M
  • mountain bike: 30M
  • curtains: 38M
  • green tea: 80M
  • sports car: 83M
  • fireplace: 85M

Over 100M (High Group):

  • nutrition: 195M
  • weight loss: 210M
  • Justin Bieber: 215M
  • tea: 300M
  • coffee: 350M
  • quotes: 410M
  • computers: 450M
  • iPad: 540M
  • Charlie Sheen: 585M
  • TV: 3.5B

Overall PageRank range for both groups was from 0-9, each broad group having at least once site PR9.

PageRank Findings

  • Average PR High Group: 5.2
  • Average PR Low Group: 3.8
  • Average WikiPedia PR: 5.9
  • 16% (17 pages from Low Group, 15 pages from High Group) were PR0
  • 22% of PR0 were Google News pages
  • 13% of PR0 were Google Images

Additional Findings

  • 75% of keywords (15/20) had a WikiPedia result
  • 4% of all results were YouTube
  • 9% of all results were either YouTube, Google News, or Google Images
  • 60% of results for ‘Charlie Sheen’ were PR0
  • 40% of results for ‘Justin Bieber’ were YouTube
  • Google News listing appeared most at SERP rank 4 (three times), and next at SERP rank 1 (two times)
  • WikiPedia appeared most at SERP rank 1 (four times), and next at SERP rank 2 and 6 (three times in each)

A Graphical Analysis

My assumption, and the assumption of many other marketers, is that a direct correlation exists between SERP rank and PageRank. In a perfect world, that would look something like this:

However, as with anything, especially in marketing, there is no “perfect world” and it is usually not safe to make assumptions.

Anyways, here are graphs of each keyword.

Low Group

High Group

When looking visually, it’s very easy to tell that not a single keyword analyzed, granted there were only 20, followed the ‘assumed’ relationship between PageRank and SERP rank.

Here’s the averages:

As you can see, the highest PageRank was actually in the top SERP spot.

However, based on the overall averages, it appears as though PageRank is not a clear-cut factor for SERP rank, although again, I only analyzed 20 results.

My Analysis

This study lead me to 6 conclusions.

  1. WikiPedia appears pretty damn often. I could be wrong here, but I thought Google penalized content farms with the last algorithm update. If you ask me, WikiPedia is a content farm of epic proportions. What’s the deal here?
  2. Analyzing 20 keywords may not be enough for this study. I realize it isn’t statistically significant anyways, but I did try to look at keywords from a variety of niches/industries, and used a wide variety of competition as well. Either way, I may have to look at this in more depth.
  3. PageRank may just be a good indicator of overall ranking ability. While the results were not staggering in favor of “a high PR guarantees a high SERP rank,” most sites with a higher PR also had more links, a longer domain age, and consequently, higher rankings.
  4. Keywords with more results generally have listings with higher PageRank. With the exception of Charlie Sheen (average PageRank of 2), no keyword in the ‘High Group’ had an average PR lower than 4.
  5. Google loves Justin Bieber.
  6. Niches with high profit potential and low competition still exist.

Although I did not take into account any other factors for SERP ranking, I feel the study was a success.

What’s Next?

First of all, I would love any comments about this study. If I receive good feedback, I’ll continue looking for similar factors to analyze whether it be with SEO, PPV, Facebook, POF, or whatever. If you liked it, simply leave me a comment, re-tweet it, or ‘Like’ it using the little widget on the left.

I truly appreciate any feedback or support YOU can give me.

Also, I am getting ready to launch my follow-along site. It’s a small niche site and I’m just going to try to rank it well for my primary keyword (originally).

Have a great week and weekend!