How to Take Advantage of Google's Stemming Technology?

Google has introduced its own word stemming search technology. It basically means that on some queries, Google looks not only for the searched keywords, but also for their variants.

Example: when you search for "Australia", Google might also look for "Australian". In this case, not only "Australia", but also "Australian" increase the relevancy of a web page for the query involving "Australia". The higher your relevancy score, the higher will be your ranking.

I want to stress a very important point. Keyword variants carry less weight than the keywords themselves. That means you shouldn't substitute your keywords for their variants, but put keyword variants in addition to the keywords themselves.

First, you have to identify the keyword variants that Google gives additional weight. It is really simple. Go to Google's site and run your query. Google shows the titles of the results, plus text snippets and highlights (bolds) the keywords and their variants which are used in the ranking process.

Google does not use word stemming for all queries. Google may use variants of a keyword in one query, and ignore variants of the same keyword in another query. Stemming is query-specific.

Now, that you have identified the additional keywords that increase your rankings, it is time to use them. I want to stress this point again: use the stemmed keyword variants wherever you can't use the keywords themselves.

The most useful places to put keyword variants are: the titles of your pages, the anchor text of the links pointing to your pages, the text and the alt image tags.

For single word queries all you have to do is place the keyword variants wherever you can't use the keyword itself.

Multi-word queries are far more interesting. You have to take into account keyword proximity and keyword order. Keyword order is VERY important. You have to place the keywords and their stemmed variants in the following way (let's say you optimize for "keyword1 keyword2"):

keyword1_variant ..some text.. keyword1 keyword2 ..some text.. keyword2_variant

Follow these four rules:

1. "keyword1(or its variant) keyword2 (or its variant)" weights more than the reversed order
2. the closer the distance between the keywords (their proximity) the higher the weight. To say it in other words: put the keyword variants of keyword1 as close to and before an instance of the "keyword1 keyword2" phrase, and put variants of the last keyword of your target query after and as close to an instance of the phrase.
3. a keyword carries more weight than its variant
4. put a keyword or its variant capitalized whenever applicable (capitalized words carry just a bit more weight)

Let's use a real world example. Consider these two queries: "diet supplements" and "dietary supplements". Run a search for both queries, look at the first 2-3 pages of the results and take a notice of all the bolded words.

For "diet supplements", Google bolds these additional word variants: "diets", "dietary", "supplement". For "dietary supplements" the only additional word variant is: "supplement". It is worth repeating again: Google does not use stemmed variants in all queries, but determines for each specific query, which variants should also participate in the ranking process.

Now, let's concentrate on the query "diet supplements". Our first priority should be putting the phrase "diet supplements" as many times as possible throughout the text and capitalize it wherever applicable. Our second priority is mentioning the word "diet" just before and very close to "diet supplements" and using the word "supplements" after and very close to "diet supplements".

Here is an example text: "Improve your Diet. Diet Supplements are very useful…". In this example we used our capitalized keywords as close as possible to each other, and in the right order. Our third priority might be putting the keyword variant "dietary" somewhere close and before "diet supplements". Example: "Your dietary habits can make or break the success of your diet. Diet supplements are invaluable addition to your.. bla bla"

1. You can optimize for two queries at the same time. (example: diet supplements and dietary supplements) By carefully selecting the order, proximity and number of keyword instances, you control the relative relevancy to both queries.
2. Sometimes over-repeating your main keywords looks very "user-unfriendly". It reads strange. In this case you can use variants, make the text more readable and at the same time well optimized. You will reap the greatest benefit by using keyword variants in your titles and anchor texts.
3. If your page has a huge PageRank, you can easily "deoptimize" it for the main keywords without losing your ranking (you will do this by using variants instead of the main keywords). At the same time you gain easy top ranking for queries that use the keyword variants.

1. Keyword variants are given less weight than the actual keywords.
2. For many queries, it is very easy to use a lot of instances of the main keywords, and keyword variants cannot contribute significantly to the ranking.
3. Google does not use variants in every query.

As a final note, I'd like to stress the main point again: use keyword variants in places where you can't use the main keywords. Although variants get less weight, their additional mentioning should contribute to ranking higher.

Sometimes high-quality (high PageRank) pages don't mention all possible keyword variants, and some lower quality pages sneak to the top. The purpose of word stemming is bringing these high rank pages upfront. Thus, stemming increases competition. It is good for you, if you have the highest PageRank, and it will be bad if you are one of the lower PR pages.

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