In the original post, his assumptions are incorrect.
The Total Unique Visitors for any given date includes spiders, but subtracting the spiders does not necessarily equal Total Unique Human Visitors. It would just equal Total Human Visitors.
I'll agree the "Visitors" reports needs tweaking, but they do a fairly good job of separating human visits from spiders/bots.
I'll use my own stats for yesterday (4/29/08) as an example. Under the report Traffic > Daily Totals:
Page Views: 21
Visits: 28
Hits: 80
This report tells me that of the 28 visits I had that day, they viewed 21 pages and there were 80 hits to those pages and other non-web page files (e.g. robots.txt file, PDF files, etc).
Under the report Visitors > Daily Visitors:
Visits: 28 (matches Traffic count)
Unique Visitors: 25 (equals New + Return)
New Visitors: 15
Return Visitors: 10
These numbers tell me that 25 different people (or bots) visited my site that day and that 3 of them visited my site twice that day.
Under the report Visitors > Spiders:
Spiders listed: 4 (Yahoo, MSN, Google, Askjeeves)
Total Page Views: 15
Total Visits: 20
Total Hits: 28
This report tells me that 4 different spiders visited my site multiple times (avg of 5 per spider), "viewed" 15 pages that generated 80 hits on my site yesterday.
But from the Total Visits and Spider Visits for that day, I can assume there were 8 human visits that day that resulted in 6 page views and 52 hits.
Total Visits: 28
- Spider Visits: 20
------------------------------
Human Visits: 8
Total Page Views: 21
- Spider Page Views: 15
-------------------------------------
Human Page Views: 6
Total Hits: 80
- Spider Hits: 28
---------------------------------
Human Hits: 52
The only thing I see that is confusing amongst all those stats is that the Daily Visitors report doesn't break out the spiders, so you don't know how many New and Return Human Visitors you have. You could probably create a custom report to get that info, but I haven't tried.
Also, "Heidi" posted this on that thread:
"I understand that New + Return = Unique visitors. For one of my web clients, the number of Unique Visitors according to the Monthly Visitors report is 1,230 for the month of March.
But for that same client and the same period of time (the month of March), the Unique Visitors count from the Daily Visitors report -- if I add up all of the Unique Visitors per day -- is 2,697. Which one is correct?"
Since the web is stateless and visitors are anonymous, there is no possible way that the sum of Daily Unique Visitors for a given month will equal the Monthly Unique Visitors. It never will and Daily will always be higher than Monthly. Here's why:
On April 15th I visit a site 3 times (different browser sessions). I'm counted as 1 Unique Visitor for that day.
On April 25th I visit the same site 2 more times (different browser sessions). I'm counted as 1 Unique Visitor for that day.
On May 1st, if you run the Monthly Unique Visitors Report, I will only be counted once, not 5 times, because over the course of a MONTH, I am only counted as 1 unique visitor.
However, if on April 30th I cleared my browser cookies and got a new public IP address on my computer/router and visited the same site one time, the Monthly Unique Visitors Report would count me twice.
Sorry for the long post, but hopefully that clears some things up.
William Eaton, MCSE
iTech Computer Solutions, LLC
www.itechcs.com