In the last newsletter, we presented an overview of testing and optimization practices. This month we'd like to focus on the experimental design and technology options available for implementing those techniques.
Experimental Design Overview
There are some basic principles to follow as you design the experiment. Experience will guide you going forward but, in the beginning, the following tips may prove useful.
Choosing the Variables to Test
Choosing which variables to test is not an easy step in the process. The possibilities are infinite and it is not something that can be calculated. All websites have certain variables that are going to produce better results than others, but it can be difficult to identify them. Experience may help in quickly identifying low hanging fruit, but even with experience there may inevitably be some unexpected variable which has potential to produce great results.
The following variables are some of the fundamental places to start:
Size, order and color can also impact the effectiveness of each of the above items.
There are 4 basic ways to implement a test:
Place code directly on the site-
The first option requires placing code directly on the site, which handles the assignment and tracking of visitors into the various test groups.
Use an ASP Service-
Another option would be to use an ASP service, which requires a small piece of code to be placed on each of the test pages that accesses more complex code from the ASP provider to administer the test.
Install software on the server-
A third method would be to install a software agent on the web server that monitors all of the requests. It can also handle all of the assignment and tracking of visitors into the various test groups.
Install hardware within the network-
Lastly, a hardware device could be installed upstream of the web server that handles the assignment and tracking of visitors into the various test groups.
As you can see, all four options have distinct strengths and weaknesses. It is important to evaluate the needs of the organization and the resources available in order to choose the best option for your organization.
Bill Bruno is the CEO - North America, Ebiquity.