I’ve combed the Internet to learn what I can about Penguin 2.1. One of my most interesting discoveries is how U.K.-based MathSight used reverse engineering to analyze websites impacted by the algorithmic update to determine what factors resulted in the site being hit.
MathSight’s data reveals a secret… websites that gained and lost traffic from Penguin 2.1 had links from web pages with the following:
- Body text with a higher (good) or lower (bad) number of words per sentence
- Body text with a higher (good) or lower (bad) proportion of rare words
- Body text with a higher (good) or lower (bad) number of syllables per word
MathSight’s data supports the belief that linking to poor quality sites is bad, and that the “quality” factor is determined by content. It seems that content from a linking page is highly influential to how Penguin views the site being linked to.
Bottom-line: Penguin 2.1 judges content to be more authentic based on how intellectual the text reads.
Penguin 2.1 and Metrics
RE = 206.835 – (1.015 x ASL) – (84.6 x ASW)
The formula explained: Readability Ease (RE). The Average Sentence Length (ASL) is the number of words divided by the number of sentences. The average number of syllables per word (ASW) is the number of syllables divided by the number of words.
Analysis of variance (ANOVA) statistics proved by 99.999 percent that the Flesch-Kinkaid scale is causing a change in traffic due to Penguin, according to MathSite.
The more difficult a page’s text is to read, the more favorable content is for Penguin algorithm updates.
How to Update Your Website for Penguin 2.1
The statistics tell us Google is using readability. We don’t know why. It could be that Google thinks readability is an easy way of overlooking non-expert guest post links.
SEO professionals can manually check each link of web page content for Flesch-Kincaid and Dale-Chall readability by using these free online tools:
- Readability.info. Upload and test a web page or Microsoft Word document for Flesch-Kincaid Reading Ease, SMOG Index, Gunning-Fog Score, Coleman-Liau Index, and Automated Readability Index. It also adds Kincaid and Lix formulas, too.
- OnlineUtility.org. Test a web page or a block of text for Flesch-Kincaid Reading Ease, Flesch-Kincaid Grade Level, Coleman-Liau Index, Gunning Fog Score, Automated Readability Index, and SMOG Index.
- Microsoft Office Outlook and Word: Measures your document content for Flesch-Kincaid Reading Ease and Flesch-Kincaid Grade Level.
Test your web pages. You can then decide to disavow the links or recondition a site’s landing page content.
For mathematical formulas and readability test metrics, see this Ideosity readability resource.