Recently, there has been some discussion on statistics, both over at “Asa Dotzler’s blog”:http://weblogs.mozillazine.org/asa/archives/008076.html and in “other places”:http://operawatch.blogspot.com/2005/05/operas-market-share.html.
Could we all please stop this nonsense? Browser statistics are rather uninteresting, since they are fairly likely to be invalid, even within one single domain/site. If applied across domains, they are even more invalid.
I have spent quite some time looking at what is happening in my own server logs, and I have made some observations
Text-only browsers without scripting capabilites are, on average, undercounted by a factor of around 3.2 when visiting this site: These browsers do not fetch any associated style sheets, scripts or images, and hence will always be undercounted.
As for Opera: Opera has a much more aggressive caching policy than the competing browsers — it mostly doesn’t verify the document with the server when going back and forward, but instead fetches them from the RAM Cache. How severe the undercounting of Opera is due to this aggressive caching is not measurable, unless I want to pay a visit to each and every one of my users and observe how they use their back and forward functions.
First, let’s start with browsers in the Gecko family: They support a feature called “prefetching”:http://www.mozilla.org/projects/netlib/Link_Prefetching_FAQ.html where the browser under certain conditions will fetch documents without user interaction. For this reason, sites that use links with the @rel=”next”@ and @rel=”prev”@ relationships will be subject to some overcounting of browsers in this family.
Internet Explorer is subject to several distinct forms of overcounting:
Spambots or other rogue spiders of all kinds tend to identify themselves as IE. So far in 2005, I have 403’ed around 20000 requests from such bots, and even so, quite a number of rogue spiders have gotten through. This means that IE will always be somewhat overcounted.
Depending on which tool is used to gather stats, IE may be overcounted at the expense of Opera. “I wrote about this”:http://virtuelvis.com/archives/2003/02/properly-measuring-msie in 2003, and “revisited the issue”:http://virtuelvis.com/archives/2003/04/msie-not-msie-revisited a few months later, where I found the following:
bq. 35.2% of browsers that claim to be MSIE aren’t. 84.2% of browsers that use a faked MSIE UA string, are using Opera.
In addition, certain sites that are using “conditional comments”:http://virtuelvis.com/archives/2004/02/css-ie-only to serve MSIE-specific styles, will overcount MSIE, since it will be making at least one extra request. Likewise, if a site uses conditional comments to deny MSIE some styles, MSIE will be undercounted.
h3. Download numbers
This is perhaps the most uninteresting stat you can use to compare the popularity of different browsers:
* One single download may be installed on hundreds or thousands of machines.
* A downloaded piece of software does not mean that it’s ever installed.
* Even if software is downloaded and installed, it doesn’t neccesarily mean that it’s ever used. For instance, I have probably downloaded 1.0+ builds of Firefox around 25 times, to different computers, for reinstallation purposes. I hardly ever use it. There are probably Firefox users that do the same with Opera, and there is likely MSIE users who try both browsers, only to return to MSIE or their favourite MSIE skin.
The only context in which download numbers are remotely interesting, is for the software vendors themselves: How popular is Opera 7.54 compared to Opera 8? How many people downloaded Firefox 1.0, 1.0.1, 1.0.2 and 1.0.3, respectively? _These numbers are not a good measure of “popularity” compared to the competition._
Can we please stop this statistics nonsense, and its attached flamewars? The Mozilla Foundation and Opera Software has far more important things to attend to. Such as fighting for web standards. Fighting against a innovation-hostile browser monopoly. Fighting for users.