SiteAdvisor blog

We’ve gotten a number of questions from our Preview Version users questioning our decision to classify some sites as “red” because those sites link heavily to sites that distribute spyware or adware, or collect information in order to send spam. These are sites that you’ll see where our system says they “link to red sites” (in the future, we are probably going to change the wording to say these sites are “affiliated with red sites.”)

Here at SiteAdvisor, we strongly believe in the importance of this feature. But we admit that so far we’ve done a mediocre job explaining our motivation and our initial implementation.

Here, I’ll try to explain it better.

First, it’s important to note that most spammers and spyware/adware distributors are economically motivated. People make money from this stuff -- lots of money. For example, Claria (formerly Gator) is said to have made as much as $90 million in revenues in 2003 (the last year they publicly reported their numbers) distributing what many consider to be adware, and there are dozens of major spyware/adware companies out there, not to mention all the “below the radar” companies doing it.

Second, it’s important to understand that most of these companies don’t get users to their sites all by themselves. Instead, they get traffic to their sites through what, in the Internet advertising business, are called “affiliates.” Affiliates are Web sites that get paid by other Web sites for some “action” like driving users to a site, collecting personal information like e-mail addresses, or getting users to download software with adware/spyware installed.

The point of our link analysis feature is to identify these affiliates and warn users about them before it’s too late.

Case Study: Freeze.com

A good way to illustrate this is to look at a company called Freeze.com. Freeze is one of many Internet businesses today that makes money by distributing free programs like screensavers that come bundled with what many anti-spyware companies consider to be adware. The way Freeze loads this stuff on users’ PCs is primarily by announcing to the world: "We'll pay anyone $1 for every time they get a user to download our programs." Check it out yourself.

This kind of affiliate marketing is extremely prevalent on the Web today. It is done all the time by well-known companies like Netflix and Citibank, but is also the preferred marketing method for companies selling less desirable products like adware.

Here’s how it works in practice. Suppose you are the savvy person who had the foresight to buy the domain name screensaver.com way back in, say, 1995. Now it’s 2005, and your site screensaver.com gets lots of traffic. Some of the users come to your site because they just type “screensaver.com” directly into their browser when they want to download a screensaver. Others come through search engines that rank your site as a top result for terms like “screensaver”. So you’ve got lots of visitors, but you’re not quite sure how to make money.

Enter Freeze.com. Freeze says to screensaver.com (and anyone else who cares to listen): "All you have to do is get your visitors to download our screensavers, and we’ll pay you $1 for each download." According to Yahoo!'s Overture service, Internet users searched for the keyword “screensaver” more than one million times on Yahoo! in November 2005. If you also include other search engines like Google and consider similar keywords like “free screensavers,” you get many millions of searches for screensavers every month. And when you type these keywords into Google and Yahoo!, screensaver.com is one of the top natural results. While we don’t know what percentage of visitors to screensaver.com actually download their software, we think it’s safe to assume that at $1 per download, they are making a lot of money.

So you can see why affiliate marketing can be so lucrative. One side brings the users. The other side brings the “business model.”

For adware vendors and their distributors, this is a win-win bargain. The vendor gets more downloads and therefore makes more money (you can rest assured they earn well more than what they pay affiliates per download). The affiliates get a way to “monetize their traffic.” But users are big losers: they end up with adware all over their computers.

By the way, screensaver.com is a real example. As we showed in a previous blog entry, downloads on screensaver.com actually come from freeze.com.

Our linker analysis identified with “high confidence” a total of 127 affiliates of freeze.com (and many more sites that link to freeze but where the relationship isn’t strong enough for the system to call them “affiliates” with high confidence).

Our Approach to Red Linkers

We presume that users who download SiteAdvisor software wish to avoid spyware, adware, and spam. The primary purpose of these affiliates’ sites is to give you precisely those things, and they are often very effective at doing just that. This is why we classify these affiliates as “red” in our system.

We should also point out that, in many cases, what we call “links” aren’t what people in honest neighborhoods of the Web (for example, in the “blogosphere”) think of as links. On spyware/adware/spam affiliate sites, link destinations are often obscured, and in many cases the browser URL bar doesn’t change to display the target links since the “links” are actually embedded frames or direct links to downloads on other domains.

When considering how to rate sites, we often ask ourselves: "What advice would we give a family member who is a typical, casual Web user?” Would we tell that family member to avoid spyware/adware affiliates like screensaver.com? The answer we always come up with is: emphatically, yes.

Accuracy, Corrections, and Future Plans

Obviously, given that the Web is full of links between sites of all kinds, there is some "art" to deciding which ones are closely linked enough to be considered "affiliates". We're constantly improving our algorithms to try to capture sites that we think are really trying to get you to go to other sites that we've rated as "red". But if you see cases where you think our judgments are incorrect, we encourage you to leave a comment on that sites's profile page. We'll review your submission and make appropriate adjustments.

We hope this helps explain our approach to affiliate or link analysis. Please keep your feedback coming.

-- Chris Dixon