Du point de vue de l’utilisation, j’aime bien pouvoir conserver les articles de mon panier d’une session à l’autre, quand je magasine sur Amazon, Futureshop ou bien Bestbuy. De la même façon, j’utilise beaucoup de services Web en ligne comme Gmail, google calendar, google analytics, basecamp ou twitter et j’apprécie ne pas être obligé de m’identifier à chaque fois pour accéder à mes données.
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Here is a detailed discussion of Cookies and Google Analytics, which should answer pretty much any question you could possibly have, and a fantastic primer on cookies and tracking overall.
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You can't do that. Not because it is not doable via the solution I had shared but because it would be a violation of Google's terms and conditions.

But if you really want to do this then now you know how you could do this with a different web analytics tool.

-Avinash.

Let's say a visitor comes to us in month one and signs up through a landing page heavily promoting a particular feature. We store that they were shown the promotion in a visitor-scoped custom variable

In month three they then purchase the feature but do so from their work machine rather than the one they signed up on.

Because of the machine switch we wouldn't be able to correlate the two events and the efficacy of the early promotion.

That said, we haven't tested how much of an edge case this is. I think we need to do that first and If it does prove to be we will look up a GAAC.

Thank you again for the input.
- Peter

http://code.google.com/apis/analytics/docs/tracking/gaTrackingCustomVariables.html

I think setting the "scope" at a Visitor level might give you want to you (assuming your users will log in or have some other way of telling you they are the same person). Then you can use the standard reports or, like I do, cheat and just get what you want from the GA API and create your own custom reports.

If you need help then I am sure a GAAC could be happy to do so, a list is at http://bit.ly/gaac

Good luck!

Avinash.

I've been thoroughly enjoying both your blog and web analytics 2.0, thank you for taking the time to write so well on the subject.

There is one subject around cookies that seems to be rarely touched on but which becomes very important when you have a long user-cycle as we do for our online website creator.

Our users are always logged in but have life cycles of many months. With customers using different machines and taking long periods to build their site our data becomes more and more dirty as their cookies are duplicated or deleted.

We really want the cookie to be set based on our user_id rather than simply the machine.

Looking at the GA cookie it seems possible to store the user's original GA cookie then overwrite the userID portion of it with the original should they log in from a different machine. That way we can be sure that GA is correlating events with visitors consistently rather than creating two different visitors for the user who logs on both at home and at work.

Is this a reasonable approach? Can you recommend any articles that talk about how to fix this problem in either GA or Omniture (which we're also using).

Thank you in advance for your help
- Peter