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Does SPAM Peak on Wednesday?
danlor asks: "After installing a pretty good spam filter here at work, we noticed an interesting weekly trend in overall spam intercepts. They peak on Wednesday and trough o n Sunday. It is an almost perfect bell curve. We have gone over this quite a few times here, but cannot come to consensus on why this would be. Could Spammers really be God fearing? Why would Spammers have a 'hump' day?" Has anyone else noticed this trend?
Got any graphs or anything compiled from your findings?
That would account for the wednesday peek and sunday valley. Or during the week is when there is the most net traffic in general and this helps to cover up their activities. Allows them to become "lost" in the sea of data.
NarratorDan
"If you're not confused by quantum mechanics, you really don't understand it." - Niels Bohr
Of course getting inside the mind of a spammer would be something that would require danger pay.
Hmm... all these people really need to know about herbal vigara... and I'll be the one to sell it to them!!
There is only one satisfying way to boot a computer. -- J. H. Goldfuss
I didn't see a clear explanation of your product's methods for spam filtering, but if it's anything like other products that judge email to be spam based on the votes of the users who see it, it could simply be a matter of workers blocking mail on monday, that other workers block on tuesday, that builds to a crest on wednesday and then falls off because in the end of the week, you have already recieved the emails that were judged to be bad on monday (but were still coming). Acutally, this sounds stupid now that I mention it, but there could be a similar building effect. With all the relays that spam bounces through, it's possible that you could be recieving messages late, and as spammers take a weekend off, your messages drop off dramatically. Just a thought.
Remember, there were no nuclear weapons before women were allowed to vote.
Analyzing 11,560 spam emails that have come to my inbox over the last few years, here is the distribution over the days of the week: (What a pain it is to get a graph to reproduce correctly on slashdot!)
While it does show a "bell" with a peak on Wednesday and a dip on Sunday and Monday, it's certainly not significant. 20% less email on the lowest vs. the highest day isn't significant in my mind.
(Statistics generated with MailListStat from freshmeat.
Many people don't read their emails the weekend (workers, students, etc.). So, it's typical that a monday morning in-box is always almost full.
Many people I know, keep cleaning their inbox until tuesday indeed! So, Wednesday might be a safe day for spamming, as inboxes are emptier.
There was an article about an email marketing conference (the legit kind) on Wired news a little while ago - maybe last month? It said that response rates for discretionary spend products were highest on a Thursday. I imagine that if so, spammers know this too, and are sending out on a Wednesday to be in your mailbox Thursday AM.
I get most of my spam on Sunday and Monday. It'll probably even out when my spammers and your spammers trade lists with each other.
Alex.
Don't worry, he didn't leave with his kneecaps.
But before I uncapped him, I was able to glean this much about their mailing habits: apparently, whether true or not, there is a prevailing idea in the spam community that Wednesday mid-morning is the best time to send spam.
There idea is that this maximizes the likelihood of it being read; they consider weekends not to be important because people are occupied with funner things than spam; they consider Monday and Tuesday to be "warmup" days into the week, when people may actually be doing work. Thursday and Friday they consider "slackoff" days in which people not only don't do work, but don't read email either. So that leaves Wednesday. And if you analyze your logs further, I bet you'll find that the peak within Wednesday is mid-morning, not the grogy, naptime after lunch hours. That's what I see with my filter, anyway.
It's all going according to
I've been saving most of my spam for the past year or so. A quick scan of my spam folder shows the following breakdown, sorted by frequency:
Or, for the same data as a histogram (line length divided by 25):
Wednesdays are pretty much in the middle of the range (the mean is 824.9).
The bigger trend I've seen was a big spike back in May, but the rate has sloped off considerably since then, as this chart of month over month spam trends shows (line length is again divided by 25):
(The script that generated this is available on request.) A major cause for this change in trends may be a change in email address around then, but even before the switch I was seeing a dropoff in the number of spams I was receiving. If this pattern is more general than just my mailbox, I have no idea what's causing it.
Disclaimer: no general trends are implied, this is just "back of the envelope" analysis of the spam mail I personally receive. As noted above, if anyone wants the shell scripts that generate these charts, you're welcome to them -- they're just a few lines of Bourne code that scan over my mbox mailboxes. If you use something other than mbox mail storage, the script may or may not do you any good, but if you want it, ask. :-)
DO NOT LEAVE IT IS NOT REAL
At the University where I administer a Linux mail server, I have noticed that my graphs for Incoming mail, Outgoing mail, and Incoming spam always make nice little bell curves every week. For Saturday and Sunday, each graph drops to very low levels (almost flatline when scaled with the rest of the weeks mail). It all shoots up Monday morning starting around 7:30 when everyone gets into work. Tuesday is always a little higher than Monday, and Wednesday is the highest for all Incoming,Outgoing and Spam. Thursday is almost always very close to Tuesday and Friday is almost always very close to Monday.
This seems to be attributed to human nature. There is more correspondence going on Wednesday's because people just don't feel like doing as much work on Monday's and Friday's.
-----BEGIN GEEK CODE BLOCK----- Version: 3.12 GIT d? s: a-- C++++ UL++++ P++ L+++ E- W++ N o-- K- w--- O- M+ V PS+ P
I've noticed the Wednesday peak in the accounts attached to my business. Those are primarily the inkjet cartridge, diploma, "forbidden CD," prescription pharmaceutical, hot stock tip, and those obnoxious idiots at Logosaurus. In other words, the spam has a higher "tone" if you will.
The spams to my Hotmail account spike on Friday evenings. Those are what I would call the "dregs of humanity" spams--the assorted barnyard animals, herbal enhancements, and general "Are you lonesome tonight" spams. They're also more likely to be inept, such as having a "TO" field that reads "C:\documents\addressfile.txt" or words to that effect.
Bagnallb at AOL is sort of my own personal spammer (although I share him with many other people on the greater Internet). He really, really wants to take over my domain, and he manifests this by increasingly frenetic efforts to find an obsolete version of FormMail. He's been trying without success for six weeks now, and his efforts always, always increase on Wednesdays.
So I'd say Wednesdays for the "business class" spam and Fridays for the really scummy stuff. Bagnallb is scummy, but he's a Wednesday sort of fellow.
DUCT TAPE: The Election Supervisors' Secret Weapon
Monday - Check mail from the weekend. If no new lawsuits, laze through the day like everyone else.
Tuesday - Write some spam.
Wednesday - Send out spam.
Thursday - Await responses to spam.
Friday - Deposit ill-gotten gains in the bank, take off early for the weekend.