CainIV - 6:21 pm on Oct 1, 2008 (gmt 0)

Hi guys, I am doing an interesting experiment on two of my more throw away domains. The experiment is testing to try and determine more information about how linking to the homepage affects rankings. The testing involves various controls - linking to the root domain from the nav only using 'home', linking from the nav using 'main keyword', linking from nav using 'variations' of keyword, linking from content only (while nav links saying home) to home using 'keywords' etc, etc.

First, I should mention some points about the domain.

4 years old
Owned by me
Dedicated IP
Canonical comdomized
HTML only
Ranks top 5 in Google.com for main, second and third keyword phrases.
Total of 90 pages, all unique content (written by me)

Testing was done over a 3 month period, with grace periods in between testing.

Here is so far what I have found. Might tell us a little about the threshold and re ranking filters

1. Linking home from every page in content using the same keyword caused 6 page drop in rankings.

2. Linking home using keyword in nav on all pages caused the same drop.

3. Link home from every page in content using variations caused a 3 page drop.

4. Linking home from the first 10 pages listed in google.com for site:domain.com/* brought increased ranking (from 5th to 3rd)

What is really interesting is that I gotten this down to the 'by page' factor. When I *slightly* cross the threshold and add links to two extra pages, and then wait until they are cached, I tip the scales and drop, to page 6.

What is further interesting is that linking home from content using variations of keywords WAS quite effective to a point, after which the site plummeted.

As well, this might point to a 'hard line' being crossed in terms of threshold, at one point I had the website going between position 4 and 51-60 for the same keyword every second day (flipping back and forth)

My test will be about trying to -950 the website by being ridiculously deliberate in nav linking, and then seeing if I can reverse the results by removing those (and how long it takes for the trust to be reinstated to the website)

Any thoughts?