Piwik : open source Web Analytics

Piwik Dashboard


Piwik, an open source alternative to Google Analytics, is a downloadable, open source (GPL licensed) real time web analytics software program. It provides you with detailed reports on your website visitors: the search engines and keywords they used, the language they speak, your popular pages, …

Piwik is a PHP MySQL program that is installed your own webserver. At the end of a five minute installation process, a JavaScript code is generated that you embed in the webpages you want to track.

Google Website Optimizer

Google recently launched the Website Optimizer, a tool that can help you improve the effectiveness of your website by allowing you to test different versions of your site content to determine what will best attract users.

Website Optimizer uses two types of testing: A/B testing and multivariate testing.

An A/B experiment allows you to test the performance of two (or more!) entirely different versions of a page. You can change the content of a page, alter the look and feel, or move around the layout of your alternate pages; there’s plenty of design freedom with A/B testing.

Multivariate tests, on the other hand, allow you to test multiple variables — in this case, sections of a page — simultaneously. For example, you could identify the headline, image, and promo text as parts of your page you’d like to improve, and try out three different versions of each one.

A/B experiments are the simpler version of testing with Website Optimizer. Experiments can run on many webpages of a website.

Website Optimizer needs a Google Analytics Account, because it uses the same powerful tracking technology that is used in Google Analytics to collect experiment data. The performance of experiment pages won’t be impacted, with the possible exception of the very first page-load after you have added the tracking code.

A quick start guide is available at the Google site. Different test strategies are possible (time on page,¬† conversions, clicking rates, landing pages, …).

Website Optimizer scripts will fail W3C validation because they meet browser requirements which do not strictly adhere to the W3C guidelines. There is no workaround available for these errors.

Understanding Google Analytics

During the creation of a new website, I was able to have a closer look on the internal working of Google Analytics. Four computers were used to test the first layout of the new website connected to three different IP adresses. The setup was the following :

  • PC 1 : Windows XP, screen resolution 1024 x 768, three browsers : IE 8.0.6001, Firefox 3.08, Chrome 1.0.154.153
  • PC 2 : Windows XP, screen resolution 1024 x 768, three browsers : IE, Firefox, Chrome
  • PC 3 : Windows XP, screen resolution 1280 x 1024, browser IE
  • PC 4 : Windows Vista, screen resolution 1280 x 800, browser IE

Google Analytics reported 18 visits from 8 unique visitors during two days, which is correct if every used browser is considered as a unique visitor (use of cookies). The reported screen resolutions, operating systems, browser versions and flash versions were correct.

The unique pageviews can not be higher than the total number of unique visitors, which was the case. The 18 visits were segmented in 8 visits from new visitors and 10 visits from returning customers.

Customer loyalty

Customer loyalty

In the visitor loyalty report, the visits were indicated as :

  • 1 times : 8
  • 2 times : 5
  • 3 times : 3
  • 4 times : 1
  • 5 times : 1