If someone has been spamming you with dumb comments here is a method to find who they are without even having advanced analytics knowledge.
This assumes you use WordPress Blogs.
See the screenshot of comment to get the IP Address.
It appears below each comment as a number like 89.99.139.67 or see below- the place for the Mouse Pointer
From Wikipedia
http://en.wikipedia.org/wiki/IP_address
“A name indicates what we seek. An address indicates where it is. A route indicates how to get there.”
Take the number and search it here
Thats the American Registry for Internet Numbers.
or Search it here.
Now that you know your friendly spammer is what do you do next
Forgive them
Tis the season of Joy.
DECISION STATS 
