Counting Uniques

[vabtz]

I want to make sure I compare apples to apples when I here people talk about their uniques.

How do you count your uniques?
Is there a standard way / program?

Different stats package come up with wildly different numbers for me and I am not sure what to believe.

I have a great counter though so internally I can measure differences from one day to the next.

[JonR28]

we use WebTrends and DeepMetrix.

Either WebTrends numbers are bloated, or DeepMetrix numbers are too low... we just take the average between the two.

[europeforvisitors]

There's no surefire way to track unique visitors, so programs and tracking services are forced to use their own assumptions in determining what a "unique visitor" is.

The Analog documentation has a pretty good explanation of this; scroll down to the "What you can't know" section:

[analog.cx...]

[larryn]

vabtz,

Different packages count different ways, the package I use has a heirarchy as follows:

Session ID
Login & Agent
IP & Agent (with allowances for dynamic IP's)
Agent & Path
IP & Path

But it does depend upon the package - my research has indicated most use match on IP & Agent, which results in mis-counts due to dynamic IPs (like from AOL). The best way to cross-check is to total the number of external referrals + direct links to your site (you are logging referrers and agents aren't you...).

HTH,

Larry