When e-merchants first begin an online advertising campaign, it's not uncommon to feel as if they are treading on foreign territory, without a guide. Since funds for most start-up e-commerce sites are limited, dropping money into an ad campaign, not knowing if anyone will respond to the ads, or which ads in which locations will bring in the most qualified visitors can bring fleeting moments of terror. Afterall, with this new advertising medium called the Web, precise target marketing has become an exact science. Rest assured that once you've been advertising for a while, and tracking the results of ads, those feelings that you've been wasting a small fortune should begin to dissipate as you see exactly which ads are working on which sites and in which magazines.

For E-merchants looking to identify the originating source of customers can be as easy as adding some code to your banners, or adding a special page to your site, as you'll see in the following sequence of steps; for print ads, it may be a bit more complex. (The examples given are based on the assumption that your site is database-backed. If it's not, jump down to the static sites section.)

Step 1. Create a Source ID Table
For each ad you run -- that's each individual banner on each individual site you advertise -- associate a source ID (or link ID). Be sure you keep track of which source ID goes with each banner/site combination, or none of this will mean anything once you have the visitor data in hand. I suggest you add this table to your main page. The table can be as simple as:

Source_ID   Banner          Site        Destination   Begin_date   End_date
001   "Stop losing money"   Money.com   Finance.cfm   10/1/98      10/14/98
002   "Get their attention" About.com   deals.cfm     4/1/99       5/31/99

Step 2. Attach a Source ID to Each Ad
Whenever you give an advertiser (or your ad agency) an ad you want them to run, instead of just giving them your URL (e.g. www.overtheweb.com), give them the destination of your landing page with the source ID attached to it. You can attach the source ID using a CGI parameter (e.g. www.overtheweb.com/landing.cfm?source_id=001, where source_id is the variable name on your system, and 001 is the source_id for this ad).

Step 3. Create a Landing Page
The landing page should do three things. First, it should take the value of the source ID and store it somewhere as a hash mark. At a minimum, this will tell you how many click-throughs you're getting from a particular ad. If you're obsessive, like me, you'll also record the day, time, day of the week, browser version, etc. for each visitor, so you know a bit more about which ads are effective when and to whom.

Second, it should set a cookie on the visitor's computer either with the source ID or with some other useful data. Why a cookie? So you can look for the cookie during the checkout or the sign up to see which sources are most effective at closing sales. The nice things about cookies is that you can use them across visits, so you can see which ads on which sites bring you the most loyal customers; those are the ones worth paying for!

Finally, the landing page should transparently route the visitor to the destination page. For print ads, you probably want to create a doorway page for each ad (e.g. www.overtheweb.com/stoplosingmoney.cfm), and do the first two activities of a landing page on the doorway page. The doorway page should look and read enough like the ad that there's a convergence experience. Don't advertise in print a product that's buried in your site then tell the reader to go to your home page. Give him the (uncomplicated) URL of the doorway page and tag him on the way in. You're not going to have much luck if you try to get him to type the CGI parameter, so just skip it and give him the page he expects, doing the processing on your side behind the scenes.

Step. 4 Record the Source ID with Personal Information the Visitor Provides
When the visitor finally decides to make a purchase or sign up for a service, record the source ID with the rest of the personal information you collect. This way you'll always be able to query your database and see which ads and/or which sites bring in the big-ticket sales, the most traffic, and lead to a closed sale. You'll also know which days of the week and which times of day your ads do best.

Little Guys & Static Sites: If your site does not have a database back-end, you are going to have to rely on traffic analysis tools, such as those discussed in Analyzing Traffic On Your E-Commerce Site. Traffic analysis tools will be most effective if you create doorway pages, as described above, for each of your ads so that you can, at a minimum, track how much traffic came through each doorway page. The alternative is to ask some basic questions, such as where the visitor heard about you, during the checkout or sign up, but these results are notoriously unreliable.

Alexis D. Gutzman
E-commerce Technology Author and Consultant
Author, The HTML 4 Bible, ColdFusion 4.5 for Dummies

Got a technical question and need expert advice? Why not ask our EC Tech Advisor!