With each traffic source used to drive visitors to your website, you can use different media specific to that source. For example, you can receive traffic from Google using either organic media or a paid placement. The following are the common media used to drive traffic in a campaign:

The analysis that comes from segmenting data based on its medium can reveal a lot of information about your visitors, as well as the effectiveness of traffic coming through a particular medium. We generally like to combine the traffic source and medium in our conversion analysis. At a minimum, we recommend segmenting your website data into the following buckets:

We usually like to compare traffic from the same source but from different media (organic or paid). Table 2-10 shows an example of the breakdown of a PPC campaign on the three major search engines: Google, Yahoo!, and Bing. The last column shows that the campaign drove a total of 51,280 visitors to the landing page at a cost of $18,932.90, generating 607 conversions. The overall campaign conversion rate is 1.18% (607 / 51,280).

When you look at the segmented data, however, you will notice that traffic from different sources converted at different levels. Visitors from Bing converted at 0.77%, compared to an average conversion rate of 1.33% for visitors from Yahoo! and 1.23% for visitors from Google. At first glance, you may think you should focus on Google and Yahoo! and drop Bing from your advertising campaign. However, when you examine the cost per conversion, you can see that Bing has a much lower cost per conversion compared to Google. Although Bing traffic completed fewer transactions, it made up for it with the lower cost per click. Again, look beyond the obvious trends to gauge the most effective use of your marketing dollars.