How accurate is Conversion Tracking

How many conversions are not measured by AdWords Conversion Tracking?

[marek]

AdWords conversion tracking relies on permanent cookies and a script running on another server. As a result, some conversions are not counted, because:

• Not everyone has permanent cookies enabled.
  
• Some visitors make purchase after 30 days of cookie experation.
  
• Some visitors make purchase from another computer.
  
• Sometimes the tracking image doesn't load before the visitor leaves the conversion page.
  

The question is, how many conversions are not included in the AdWords stats. 10 percents? Less? More?

[Robsp]

Marek,

This is very dependant on your target customers and your inustry. I'm finding that in some businesses (like adult) people surf at their job and order at home.

[ffctas]

Hi,
This is an important question because of its ramifications for ROI. If you assume a 10% "slipage" due to the above mentioned the effects on your return will be huge. Imagine if you were told that your break-even or marginally losing campaign was, in fact, a winner. Please more thoughts on this subject.

Thanks
tom

[Sanenet]

Best way - send the adwords clicktrus to a specific page, then track them to the signup page, using a combo of cookies and server logs.

[onlineleben]

>>Sometimes the tracking image doesn't load before the visitor leaves the conversion page.
<<

Any idea on what to do when you cannot place the tracking code on the final action page (eg. newsletter signup, order page)? This is when that page belongs to a merchant.
My problem: adwords go to my site - landing page is pre-selling the product - visitor clicks and is forwarded to merchant by php script (to log the clickthrough).
Since the script forwards directly without any pause, there is no chance to execute the tracking code from Google. Any idea on how to deal with this?

[redzone]

onlineleben,

Do you have control of your order/signup confirmation page? If so, put the tracking code there....

[onlineleben]

If I had control, I would do that. But I only have the possibility to link to the merchants site.
Right now I have a link tracker in place, (php redirect header ), but this doesn't allow me to execute the tracking code. And i want to have an inexpensive (free) event tracking like google ad #XX was clicked on and the user arrived/was forwared at/to the merchants site.
Looks, like it is not possible this way.

[redzone]

Most of the web analytics services that are independent of GAW conversion tracking, use both cookies and session ID's, so if the browser doesn't accept cookies, the sessionID tracking picks up and tracks the visitor.

[Tropical Island]

I have my tracking set up for "money" pages. In other words if the visitor drills through the site and lands on one of our prices pages I figure that's a win.

Because we also do some very specific services I have a few ads aimed directly at some of these "money" pages so the clicks should all be 100%.

Because of the reasons listed above this does not always happen and after doing a "7 day" and "this month" check the non registered clicks are insignificant - less than 2%.