SEO
A Guide to Star Ratings on Google and How They Work
The elusive five-star review used to be something you could only flaunt in a rotating reviews section on your website.
But today, Google has pulled these stars out of the shadows and features them front and center across branded SERPs and beyond.
Star ratings can help businesses earn trust from potential customers, improve local search rankings, and boost conversions.
This is your guide to how they work.
Stars And SERPs: What Is The Google Star Rating?
A Google star rating is a consumer-powered grading system that lets other consumers know how good a business is based on a score of one to five stars.
These star ratings can appear across maps and different Google search results properties like standard blue link search listings, ads, rich results like recipe cards, local pack results, third-party review sites, and on-app store results.
How Does The Google Star Rating Work?
When a person searches Google, they will see star ratings in the results. Google uses an algorithm and an average to determine how many stars are displayed on different review properties.
Google explains that the star score system operates based on an average of all review ratings for that business that have been published on Google.
It’s important to note that this average is not calculated in real-time and can take up to two weeks to update after a new review is created.
When users leave a review, they are asked to rate a business based on specific aspects of their customer experience, as well as the type of business being reviewed and the services they’ve included.
For example, “plumbers may get “Install faucet” or “Repair toilet” as services to add,” and Google also allows businesses to add custom services that aren’t listed.
When customers are prompted to give feedback, they can give positive or critical feedback, or they can choose not to select a specific aspect to review, in which case this feedback aspect is considered unavailable.
This combination of feedback is what Google uses to determine a business’s average score by “dividing the number of positive ratings by the total number of ratings (except the ones where the aspect was not rated).”
Google star ratings do have some exceptions in how they function.
For example, the UK and EU have certain restrictions that don’t apply to other regions, following recent scrutiny by the EU Consumer Protection Cooperation and the UK Competitions and Market Authority about fake reviews being generated.
Additionally, the type of rating search property will determine the specifics of how it operates and how to gather and manage reviews there.
Keep reading to get an in-depth explanation of each type of Google star rating available on the search engine results pages (SERPs).
How To Get Google Star Ratings On Different Search Properties
As mentioned above, there are different types of Google star ratings available across search results, including the standard blue-link listings, ads, local pack results, rich snippets, third-party reviews, and app store results.
Here’s what the different types of star-rating results look like in Google and how they work on each listing type.
Standard “Blue Link” Listings And Google Stars
In 2021, Google started testing star ratings in organic search and has since kept this SERP feature intact.
Websites can stand out from their competitors by getting stars to show up around their organic search results listing pages.
How To Get Google Stars On Organic SERPs
If you want stars to show up on your organic search results, add schema markup to your website.
Learn how to do that in the video below:
As the video points out, you need actual reviews to get your structured data markup to show.
Then, you can work with your development team to input the code on your site that indicates your average rating, highest, lowest, and total rating count.
Once you add the rich snippet to your site, there is no clear timeline for when they will start appearing in the SERPs – that’s up to Google.
In fact, Google specifically mentions that reviews in properties like search can take longer to appear, and often, this delay is caused by business profiles being merged.
When you’re done, you can check your work with Google’s Structured Data Testing Tool.
Adding schema is strongly encouraged. But even without it, if you own a retail store with ratings, Google may still show your star ratings in the search engine results.
They do this to ensure searchers are getting access to a variety of results. Google says:
“content on your website that’s been crawled and is related to retail may also be shown in product listings and annotations for free across Google.”
If you want star ratings to show up on Shopping Ads, you’ll have to pay for that.
Paid Ads And Google Stars
When Google Stars appear in paid search ads, they’re known as seller ratings, “an automated extension type that showcases advertisers with high ratings.”
These can appear in text ads, shopping ads, and free listings. Both the star rating and the total number of votes or reviews are displayed.
In addition to Google star ratings, shopping ads may include additional production information such as shipping details, color, material, and more, as shown below.
Paid text ads were previously labeled as “ads” and recently have been upgraded to a “sponsored” label, as shown below.
How To Get Google Stars On Paid Ads
To participate in free listings, sellers have to do three things:
- Follow all the required policies around personally identifiable information, spam, malware, legal requirements, return policies, and more.
- Submit a feed through the Google Merchant Center or have structured data markup on their website (as described in the previous section).
- Add their shipping settings.
Again, some ecommerce sellers who do not have schema markup may still have their content show up in the SERPs.
For text ads and shopping ads to show star ratings, sellers are typically required to have at least 100 reviews in the last 12 months.
Paid advertisers must also meet a minimum number of stars for seller ratings to appear on their text ads. This helps higher-quality advertisers stand out from the competition.
For example, text ads have to have a minimum rating of 3.5 for the Google star ratings to show.
Google treats reviews on a per-country basis, so the minimum review threshold of 100 also applies only to 1 region at a time.
For star ratings to appear on a Canadian ecommerce company’s ads, for example, they would have to have obtained a minimum of 100 reviews from within Canada in the last year.
Google considers reviews from its own Google Customer Reviews and also from approved third-party partner review sites from its list of 29 supported review partners, which makes it easier for sellers to meet the minimum review threshold each year.
Google also requests:
- The domain that has ratings must be the same as the one that’s visible in the ad.
- Google or its partners must conduct a research evaluation of your site.
- The reviews included must be about the product or service being sold.
Local Pack Results And Google Stars
Local businesses have a handful of options for their business to appear on Google via Places, local map results, and a Google Business Profile page – all of which can show star ratings.
Consumers even have the option to sort local pack results by their rating, as shown in the image example below.
How To Get Google Stars On Local Search Results
To appear in local search results, a Google Business Profile is required.
Customers may leave reviews directly on local business properties without being asked, but Google also encourages business owners to solicit reviews from their customers and shares best practices, including:
- Asking your customers to leave you a review and make it easy for them to do so by providing a link to your review pages.
- Making review prompts desktop and mobile-friendly.
- Replying to customer reviews (ensure you’re a verified provider on Google first).
- Be sure you do not offer incentives for reviews.
Customers can also leave star ratings on other local review sites, as Google can pull from both to display on local business search properties. It can take up to two weeks to get new local reviews to show in your overall score.
Once customers are actively leaving reviews, Google Business Profile owners have a number of options to help them manage these:
Rich Results, Like Recipes, And Google Stars
Everybody’s gotta eat, and we celebrate food in many ways — one of which is recipe blogs.
While restaurants rely more on local reviews, organic search results, and even paid ads, food bloggers seek to have their recipes rated.
Similar to other types of reviews, recipe cards in search results show the average review rating and the total number of reviews.
The outcome has become a point of contention among the food blogging community, since only three recipes per search can be seen on Google desktop results (like shown in the image above), and four on a mobile browser.
These coveted spots will attract clicks, leaving anyone who hasn’t mastered online customer reviews in the dust. That means that the quality of the recipe isn’t necessarily driving these results.
Google gives users the option to click “Show more” to see two additional rows of results:
Searchers can continue to click the “Show more” button to see additional recipe results.
Anyone using Google Home can search for a recipe and get results through their phone:
Similarly, recipe search results can be sent from the device to the Google Home assistant. Both methods will enable easy and interactive step-by-step recipe instructions using commands like “start recipe,” “next step,” or even “how much olive oil?”
How To Get Google Stars On Recipe Results
Similar to the steps to have stars appear on organic blue-link listings, food bloggers and recipe websites need to add schema to their websites in order for star ratings to show.
However, it’s not as straightforward as listing the average and the total number of ratings. Developers should follow Google’s instructions for recipe markup.
There is both required and recommended markup:
Required Markup For Recipes
- Name of the recipe.
- Image of the recipe in a BMP, GIF, JPEG, PNG, WebP, or SVG format.
Recommended Markup For Recipes
- Aggregate rating.
- Author.
- Cook time, preparation time, and total duration.
- Date published.
- Description.
- Keywords.
- Nutrition information.
- Prep time.
- Recipe category by meal type, like “dinner.”
- Region associated with the recipe.
- Ingredients.
- Instructions.
- Yield or total serving.
- Total time.
- Video (and other related markup, if there is a video in the recipe).
To have recipes included in Google Assistant Guided Recipes, the following markup must be included:
- recipeIngredient
- recipeInstructions
- To have the video property, add the contentUrl.
For example, here’s what the structured markup would look like for the recipeIngredient property:
Third-Party Review Sites And Google Stars
Many software companies rely on third-party review sites to help inform their customer’s purchasing decisions.
Third-party review sites include any website a brand doesn’t own where a customer can submit a review, such as Yelp, G2, and many more.
Many of these sites, like Featured Customers shown below, can display star ratings within Google search results.
Rich snippets from third-party reviews, such as stars, summary info, or ratings, can also appear on a Google Business Profile or map view from approved sites.
For local businesses, Google star ratings appear in different locations than the third-party reviews on a desktop:
On mobile, ratings are displayed on a company’s Google Business Profile. Users need to click on Reviews or scroll down to see the third-party reviews:
On a map, the results from third parties may be more prominent, like the Tripadvisor review that shows up for a map search of The Hilton in Vancouver (although it does not display a star rating even though Tripadvisor does provide star ratings):
How To Get Google Stars On Third-Party Review Sites
The best way to get a review on a third-party review site depends on which site is best for the brand or the business.
For example, if you have active customers on Yelp or Tripadvisor, you may choose to engage with customers there.
Similarly, if a software review site like Trustpilot shows up for your branded search, you could do an email campaign with your customer list asking them to leave you a review there.
Here are a few of the third-party review websites that Google recognizes:
- Trustpilot.
- Reevoo.
- Bizrate – through Shopzilla.
When it comes to third-party reviews, Google reminds businesses that there is no way to opt out of third-party reviews, and they need to take up any issues with third-party site owners.
App Store Results And Google Stars
When businesses have an application as their core product, they typically rely on App Store and Google Play Store downloads.
Right from the SERPs, searchers can see an app’s star ratings, as well as the total votes and other important information, like whether the app is free or not.
How To Get Google Stars On App Store Results
Businesses can list their iOS apps in the App Store or on the Google Play store, prompt customers to leave reviews there, and also respond to them.
Does The Google Star Rating Influence SEO Rankings?
John Mueller confirmed that Google does not factor star ratings or customer reviews into web search rankings. However, Google is clear that star ratings influence local search results and rankings:
“Google review count and review score factor into local search ranking. More reviews and positive ratings can improve your business’ local ranking.”
Even though they are not a ranking factor for non-local organic search, star ratings can serve as an important conversion element, helping you display social proof, build credibility, and increase your click-through rate from search engines (which may indirectly impact your search rankings).
For local businesses, both Google stars and third-party ratings appear in desktop and mobile searches, as seen above.
These ratings not only help local businesses rank above their competitors for key phrases, but they will also help convince more customers to click, which is every company’s search game.
How Do I Improve My Star Rating?
Businesses that want to improve their Google star rating should start by claiming their Google Business Profile and making sure all the information is complete and up to date.
If a company has already taken these steps and wants to offset a poor rating, they are going to need more reviews to offset the average.
Companies can get more Google reviews by making it easy for customers to leave one. The first step for a company is to get the link to leave a review inside their Google Business Profile:
From there, companies can send this link out to customers directly (there are four options displayed right from the link as seen above), include it on social media, and even dedicate sections of their website to gathering more reviews and/or displaying reviews from other users.
It isn’t clear whether or not responding to reviews will help improve a local business’s ranking; however, it’s still a good idea for companies to respond to reviews on their Google Business Profile in order to improve their ratings overall.
That’s because responding to reviews can entice other customers to leave a review since they know they will get a response and because the owner is actually seeing the feedback.
For service businesses, Google provides the option for customers to rate aspects of the experience.
This is helpful since giving reviewers this option allows anyone who had a negative experience to rate just one aspect negatively rather than giving a one-star review overall.
Does Having A Star Rating On Google Matter? Yes! So Shoot For The Stars
Stars indicate quality to consumers, so they almost always improve click-through rates wherever they are present.
Consumers tend to trust and buy from brands with higher star ratings in local listings, paid ads, or even app downloads.
Many, many, many studies have demonstrated this phenomenon time and again. So, don’t hold back when it comes to reviews.
Do an audit of where your brand shows up in SERPs and get stars next to as many placements as possible.
The most important part of star ratings across Google, however, will always be the service and experiences companies provide that fuel good reviews from happy customers.
More resources:
Feature Image: BestForBest/Shutterstock
All screenshots taken by author
SEO
How to Revive an Old Blog Article for SEO
Quick question: What do you typically do with your old blog posts? Most likely, the answer is: Not much.
If that’s the case, you’re not alone. Many of us in SEO and content marketing tend to focus on continuously creating new content, rather than leveraging our existing blog posts.
However, here’s the reality—Google is becoming increasingly sophisticated in evaluating content quality, and we need to adapt accordingly. Just as it’s easier to encourage existing customers to make repeat purchases, updating old content on your website is a more efficient and sustainable strategy in the long run.
Ways to Optimize Older Content
Some of your old content might not be optimized for SEO very well, rank for irrelevant keywords, or drive no traffic at all. If the quality is still decent, however, you should be able to optimize it properly with little effort.
Refresh Content
If your blog post contains a specific year or mentions current events, it may become outdated over time. If the rest of the content is still relevant (like if it’s targeting an evergreen topic), simply updating the date might be all you need to do.
Rewrite Old Blog Posts
When the content quality is low (you might have greatly improved your writing skills since you’ve written the post) but the potential is still there, there’s not much you can do apart from rewriting an old blog post completely.
This is not a waste—you’re saving time on brainstorming since the basic structure is already in place. Now, focus on improving the quality.
Delete Old Blog Posts
You might find a blog post that just seems unusable. Should you delete your old content? It depends. If it’s completely outdated, of low quality, and irrelevant to any valuable keywords for your website, it’s better to remove it.
Once you decide to delete the post, don’t forget to set up a 301 redirect to a related post or page, or to your homepage.
Promote Old Blog Posts
Sometimes all your content needs is a bit of promotion to start ranking and getting traffic again. Share it on your social media, link to it from a new post – do something to get it discoverable again to your audience. This can give it the boost it needs to attract organic links too.
Which Blog Posts Should You Update?
Deciding when to update or rewrite blog posts is a decision that relies on one important thing: a content audit.
Use your Google Analytics to find out which blog posts used to drive tons of traffic, but no longer have the same reach. You can also use Google Search Console to find out which of your blog posts have lost visibility in comparison to previous months. I have a guide on website analysis using Google Analytics and Google Search Console you can follow.
If you use keyword tracking tools like SE Ranking, you can also use the data it provides to come up with a list of blog posts that have dropped in the rankings.
Make data-driven decisions to identify which blog posts would benefit from these updates – i.e., which ones still have the chance to recover their keyword rankings and organic traffic.
With Google’s helpful content update, which emphasizes better user experiences, it’s crucial to ensure your content remains relevant, valuable, and up-to-date.
How To Update Old Blog Posts for SEO
Updating articles can be an involved process. Here are some tips and tactics to help you get it right.
Author’s Note: I have a Comprehensive On-Page SEO Checklist you might also be interested in following while you’re doing your content audit.
Conduct New Keyword Research
Updating your post without any guide won’t get you far. Always do your keyword research to understand how users are searching for your given topic.
Proper research can also show you relevant questions and sections that can be added to the blog post you’re updating or rewriting. Make sure to take a look at the People Also Ask (PAA) section that shows up when you search for your target keyword. Check out other websites like Answer The Public, Reddit, and Quora to see what users are looking for too.
Look for New Ranking Opportunities
When trying to revive an old blog post for SEO, keep an eye out for new SEO opportunities (e.g., AI Overview, featured snippets, and related search terms) that didn’t exist when you first wrote your blog post. Some of these features can be targeted by the new content you will add to your post, if you write with the aim to be eligible for it.
Rewrite Headlines and Meta Tags
If you want to attract new readers, consider updating your headlines and meta tags.
Your headlines and meta tags should fulfill these three things:
- Reflect the rewritten and new content you’ve added to the blog post.
- Be optimized for the new keywords it’s targeting (if any).
- Appeal to your target audience – who may have changed tastes from when the blog post was originally made.
Remember that your meta tags in particular act like a brief advertisement for your blog post, since this is what the user first sees when your blog post is shown in the search results page.
Take a look at your blog post’s click-through rate on Google Search Console – if it falls below 2%, it’s definitely time for new meta tags.
Replace Outdated Information and Statistics
Updating blog content with current studies and statistics enhances the relevance and credibility of your post. By providing up-to-date information, you help your audience make better, well-informed decisions, while also showing that your content is trustworthy.
Tighten or Expand Ideas
Your old content might be too short to provide real value to users – or you might have rambled on and on in your post. It’s important to evaluate whether you need to make your content more concise, or if you need to elaborate more.
Keep the following tips in mind as you refine your blog post’s ideas:
- Evaluate Helpfulness: Measure how well your content addresses your readers’ pain points. Aim to follow the E-E-A-T model (Experience, Expertise, Authoritativeness, Trustworthiness).
- Identify Missing Context: Consider whether your content needs more detail or clarification. View it from your audience’s perspective and ask if the information is complete, or if more information is needed.
- Interview Experts: Speak with industry experts or thought leaders to get fresh insights. This will help support your writing, and provide unique points that enhance the value of your content.
- Use Better Examples: Examples help simplify complex concepts. Add new examples or improve existing ones to strengthen your points.
- Add New Sections if Needed: If your content lacks depth or misses a key point, add new sections to cover these areas more thoroughly.
- Remove Fluff: Every sentence should contribute to the overall narrative. Eliminate unnecessary content to make your post more concise.
- Revise Listicles: Update listicle items based on SEO recommendations and content quality. Add or remove headings to stay competitive with higher-ranking posts.
Improve Visuals and Other Media
No doubt that there are tons of old graphics and photos in your blog posts that can be improved with the tools we have today. Make sure all of the visuals used in your content are appealing and high quality.
Update Internal and External Links
Are your internal and external links up to date? They need to be for your SEO and user experience. Outdated links can lead to broken pages or irrelevant content, frustrating readers and hurting your site’s performance.
You need to check for any broken links on your old blog posts, and update them ASAP. Updating your old blog posts can also lead to new opportunities to link internally to other blog posts and pages, which may not have been available when the post was originally published.
Optimize for Conversions
When updating content, the ultimate goal is often to increase conversions. However, your conversion goals may have changed over the years.
So here’s what you need to check in your updated blog post. First, does the call-to-action (CTA) still link to the products or services you want to promote? If not, update it to direct readers to the current solution or offer.
Second, consider where you can use different conversion strategies. Don’t just add a CTA at the end of the post.
Last, make sure that the blog post leverages product-led content. It’s going to help you mention your products and services in a way that feels natural, without being too pushy. Being subtle can be a high ROI tactic for updated posts.
Key Takeaway
Reviving old blog articles for SEO is a powerful strategy that can breathe new life into your content and boost your website’s visibility. Instead of solely focusing on creating new posts, taking the time to refresh existing content can yield impressive results, both in terms of traffic and conversions.
By implementing these strategies, you can transform old blog posts into valuable resources that attract new readers and retain existing ones. So, roll up your sleeves, dive into your archives, and start updating your content today—your audience and search rankings will thank you!
SEO
How Compression Can Be Used To Detect Low Quality Pages
The concept of Compressibility as a quality signal is not widely known, but SEOs should be aware of it. Search engines can use web page compressibility to identify duplicate pages, doorway pages with similar content, and pages with repetitive keywords, making it useful knowledge for SEO.
Although the following research paper demonstrates a successful use of on-page features for detecting spam, the deliberate lack of transparency by search engines makes it difficult to say with certainty if search engines are applying this or similar techniques.
What Is Compressibility?
In computing, compressibility refers to how much a file (data) can be reduced in size while retaining essential information, typically to maximize storage space or to allow more data to be transmitted over the Internet.
TL/DR Of Compression
Compression replaces repeated words and phrases with shorter references, reducing the file size by significant margins. Search engines typically compress indexed web pages to maximize storage space, reduce bandwidth, and improve retrieval speed, among other reasons.
This is a simplified explanation of how compression works:
- Identify Patterns:
A compression algorithm scans the text to find repeated words, patterns and phrases - Shorter Codes Take Up Less Space:
The codes and symbols use less storage space then the original words and phrases, which results in a smaller file size. - Shorter References Use Less Bits:
The “code” that essentially symbolizes the replaced words and phrases uses less data than the originals.
A bonus effect of using compression is that it can also be used to identify duplicate pages, doorway pages with similar content, and pages with repetitive keywords.
Research Paper About Detecting Spam
This research paper is significant because it was authored by distinguished computer scientists known for breakthroughs in AI, distributed computing, information retrieval, and other fields.
Marc Najork
One of the co-authors of the research paper is Marc Najork, a prominent research scientist who currently holds the title of Distinguished Research Scientist at Google DeepMind. He’s a co-author of the papers for TW-BERT, has contributed research for increasing the accuracy of using implicit user feedback like clicks, and worked on creating improved AI-based information retrieval (DSI++: Updating Transformer Memory with New Documents), among many other major breakthroughs in information retrieval.
Dennis Fetterly
Another of the co-authors is Dennis Fetterly, currently a software engineer at Google. He is listed as a co-inventor in a patent for a ranking algorithm that uses links, and is known for his research in distributed computing and information retrieval.
Those are just two of the distinguished researchers listed as co-authors of the 2006 Microsoft research paper about identifying spam through on-page content features. Among the several on-page content features the research paper analyzes is compressibility, which they discovered can be used as a classifier for indicating that a web page is spammy.
Detecting Spam Web Pages Through Content Analysis
Although the research paper was authored in 2006, its findings remain relevant to today.
Then, as now, people attempted to rank hundreds or thousands of location-based web pages that were essentially duplicate content aside from city, region, or state names. Then, as now, SEOs often created web pages for search engines by excessively repeating keywords within titles, meta descriptions, headings, internal anchor text, and within the content to improve rankings.
Section 4.6 of the research paper explains:
“Some search engines give higher weight to pages containing the query keywords several times. For example, for a given query term, a page that contains it ten times may be higher ranked than a page that contains it only once. To take advantage of such engines, some spam pages replicate their content several times in an attempt to rank higher.”
The research paper explains that search engines compress web pages and use the compressed version to reference the original web page. They note that excessive amounts of redundant words results in a higher level of compressibility. So they set about testing if there’s a correlation between a high level of compressibility and spam.
They write:
“Our approach in this section to locating redundant content within a page is to compress the page; to save space and disk time, search engines often compress web pages after indexing them, but before adding them to a page cache.
…We measure the redundancy of web pages by the compression ratio, the size of the uncompressed page divided by the size of the compressed page. We used GZIP …to compress pages, a fast and effective compression algorithm.”
High Compressibility Correlates To Spam
The results of the research showed that web pages with at least a compression ratio of 4.0 tended to be low quality web pages, spam. However, the highest rates of compressibility became less consistent because there were fewer data points, making it harder to interpret.
Figure 9: Prevalence of spam relative to compressibility of page.
The researchers concluded:
“70% of all sampled pages with a compression ratio of at least 4.0 were judged to be spam.”
But they also discovered that using the compression ratio by itself still resulted in false positives, where non-spam pages were incorrectly identified as spam:
“The compression ratio heuristic described in Section 4.6 fared best, correctly identifying 660 (27.9%) of the spam pages in our collection, while misidentifying 2, 068 (12.0%) of all judged pages.
Using all of the aforementioned features, the classification accuracy after the ten-fold cross validation process is encouraging:
95.4% of our judged pages were classified correctly, while 4.6% were classified incorrectly.
More specifically, for the spam class 1, 940 out of the 2, 364 pages, were classified correctly. For the non-spam class, 14, 440 out of the 14,804 pages were classified correctly. Consequently, 788 pages were classified incorrectly.”
The next section describes an interesting discovery about how to increase the accuracy of using on-page signals for identifying spam.
Insight Into Quality Rankings
The research paper examined multiple on-page signals, including compressibility. They discovered that each individual signal (classifier) was able to find some spam but that relying on any one signal on its own resulted in flagging non-spam pages for spam, which are commonly referred to as false positive.
The researchers made an important discovery that everyone interested in SEO should know, which is that using multiple classifiers increased the accuracy of detecting spam and decreased the likelihood of false positives. Just as important, the compressibility signal only identifies one kind of spam but not the full range of spam.
The takeaway is that compressibility is a good way to identify one kind of spam but there are other kinds of spam that aren’t caught with this one signal. Other kinds of spam were not caught with the compressibility signal.
This is the part that every SEO and publisher should be aware of:
“In the previous section, we presented a number of heuristics for assaying spam web pages. That is, we measured several characteristics of web pages, and found ranges of those characteristics which correlated with a page being spam. Nevertheless, when used individually, no technique uncovers most of the spam in our data set without flagging many non-spam pages as spam.
For example, considering the compression ratio heuristic described in Section 4.6, one of our most promising methods, the average probability of spam for ratios of 4.2 and higher is 72%. But only about 1.5% of all pages fall in this range. This number is far below the 13.8% of spam pages that we identified in our data set.”
So, even though compressibility was one of the better signals for identifying spam, it still was unable to uncover the full range of spam within the dataset the researchers used to test the signals.
Combining Multiple Signals
The above results indicated that individual signals of low quality are less accurate. So they tested using multiple signals. What they discovered was that combining multiple on-page signals for detecting spam resulted in a better accuracy rate with less pages misclassified as spam.
The researchers explained that they tested the use of multiple signals:
“One way of combining our heuristic methods is to view the spam detection problem as a classification problem. In this case, we want to create a classification model (or classifier) which, given a web page, will use the page’s features jointly in order to (correctly, we hope) classify it in one of two classes: spam and non-spam.”
These are their conclusions about using multiple signals:
“We have studied various aspects of content-based spam on the web using a real-world data set from the MSNSearch crawler. We have presented a number of heuristic methods for detecting content based spam. Some of our spam detection methods are more effective than others, however when used in isolation our methods may not identify all of the spam pages. For this reason, we combined our spam-detection methods to create a highly accurate C4.5 classifier. Our classifier can correctly identify 86.2% of all spam pages, while flagging very few legitimate pages as spam.”
Key Insight:
Misidentifying “very few legitimate pages as spam” was a significant breakthrough. The important insight that everyone involved with SEO should take away from this is that one signal by itself can result in false positives. Using multiple signals increases the accuracy.
What this means is that SEO tests of isolated ranking or quality signals will not yield reliable results that can be trusted for making strategy or business decisions.
Takeaways
We don’t know for certain if compressibility is used at the search engines but it’s an easy to use signal that combined with others could be used to catch simple kinds of spam like thousands of city name doorway pages with similar content. Yet even if the search engines don’t use this signal, it does show how easy it is to catch that kind of search engine manipulation and that it’s something search engines are well able to handle today.
Here are the key points of this article to keep in mind:
- Doorway pages with duplicate content is easy to catch because they compress at a higher ratio than normal web pages.
- Groups of web pages with a compression ratio above 4.0 were predominantly spam.
- Negative quality signals used by themselves to catch spam can lead to false positives.
- In this particular test, they discovered that on-page negative quality signals only catch specific types of spam.
- When used alone, the compressibility signal only catches redundancy-type spam, fails to detect other forms of spam, and leads to false positives.
- Combing quality signals improves spam detection accuracy and reduces false positives.
- Search engines today have a higher accuracy of spam detection with the use of AI like Spam Brain.
Read the research paper, which is linked from the Google Scholar page of Marc Najork:
Detecting spam web pages through content analysis
Featured Image by Shutterstock/pathdoc
SEO
New Google Trends SEO Documentation
Google Search Central published new documentation on Google Trends, explaining how to use it for search marketing. This guide serves as an easy to understand introduction for newcomers and a helpful refresher for experienced search marketers and publishers.
The new guide has six sections:
- About Google Trends
- Tutorial on monitoring trends
- How to do keyword research with the tool
- How to prioritize content with Trends data
- How to use Google Trends for competitor research
- How to use Google Trends for analyzing brand awareness and sentiment
The section about monitoring trends advises there are two kinds of rising trends, general and specific trends, which can be useful for developing content to publish on a site.
Using the Explore tool, you can leave the search box empty and view the current rising trends worldwide or use a drop down menu to focus on trends in a specific country. Users can further filter rising trends by time periods, categories and the type of search. The results show rising trends by topic and by keywords.
To search for specific trends users just need to enter the specific queries and then filter them by country, time, categories and type of search.
The section called Content Calendar describes how to use Google Trends to understand which content topics to prioritize.
Google explains:
“Google Trends can be helpful not only to get ideas on what to write, but also to prioritize when to publish it. To help you better prioritize which topics to focus on, try to find seasonal trends in the data. With that information, you can plan ahead to have high quality content available on your site a little before people are searching for it, so that when they do, your content is ready for them.”
Read the new Google Trends documentation:
Get started with Google Trends
Featured Image by Shutterstock/Luis Molinero