Monday, August 17, 2009


Charitable donations to send email

In 2004, Mark Wegman, Peter Capek, Scott Fahlman, and I, wrote a paper about using charitable donations to “stamp” email messages as a mechanism against unwanted mass mailings (see Charity Begins at… your Mail Program (PDF)). The paper was not accepted at that year’s Conference on Email and Anti-Spam (CEAS).

In this year’s CEAS, Yahoo! presented a similar paper, profiling a micro-donation system that they’re piloting (see CentMail: Rate Limiting via Certified Micro-Donations (PDF)). Running code is always more compelling, and five years brings a change in focus.

The basic idea is that if you take a company’s or an individual’s existing donations, you can break them into small chunks of, say, one cent each, and count each of those chunks toward a “stamp” for your mail. On the theory that a spammer sending 50 million messages would not be willing to spend half a million dollars to stamp them, you can give at least some preference through your spam filtering to stamped mail.

MacGregor Campbell just wrote an article for New Scientist about Yahoo’s CentMail pilot, and he refers back to the IBM work and quotes Scott Fahlman and me (though he didn’t get the part that I’m not with IBM any more).

Here’s what he got from me:

Barry Leiba, also at IBM, points out that one of CentMail’s core features could also be a weakness, though.

People may not wish to receive messages plugging a cause they don’t agree with. “I might feel that by accepting his messages, I’m implicitly supporting his charity choices — choices that I might be vehemently against.”

I don’t think this is an insurmountable problem, but I don’t know how to get around it. Here’s the scenario in full, as I gave it to Mr Campbell:

I have a colleague whom I like and respect professionally, and with whom I get on well personally... except that we’re politically opposite. If we should start using Charity Seals or CentMail, I might feel that by accepting his messages, I’m implicitly supporting his charity choices — choices that I might be vehemently against.

Note that this issue exists whether or not we disclose the specific charities. The fact that I know what kind of organisations he’s likely to donate to is sufficient to trigger it. So we can’t mitigate this just by saying (as Yahoo! appears to be doing) that the message is stamped, without saying to what charity the sender gave money.

The responses I get to this concern are usually either

  1. “That won’t really be a problem,” which amounts to summary denial, or
  2. “We’ll only choose non-controversial charities,” which I think is somewhat naïve, and perhaps unworkable.

It might indeed be that it won’t turn out to be a problem. We won’t know that until it’s out there, and we see how it works. I worry, though, that if it does become a problem, it’ll be harder to solve at that point.

That said, I think the charitable donations thing is a good idea, worth pursuing, piloting, experimenting with. I’m eager to see how Yahoo’s program goes.


scouter573 said...

I share the concern (about implicitly supporting unintended organizations), but I think one's response depends on the billing model. If the postage is paid when the message is sent, my accepting or declining the mail has no effect -- so I might as well accept it. If the postage is paid when the message is received, then I have control and have a choice. Therefore, define payment to occur at sending.

Anonymous said...

Do you currently refuse postal mail featuring stamp designs you don't like? I assume those include all religious symbolism and messages, plus assorted politicians and other public figures.

Endorsement is in the eye of the sender. You're under no more obligation to like or endorse the postage message than you are to follow all instructions written on envelopes.

I'd pay no more attention to where an email's penny postage was going than I do now to various Web ads that winkle and twinkle trying to distract me from the content I'm trying to read.

Barry Leiba said...

I don't refuse paper mail that supports organizations I don't like, because I have no reasonable way to do it. But I'd like to do so.

With email, I can — there's a way in the email protocol to refuse a message, and if my email provider supports Sieve (RFC 5228) and its Reject extension (RFC 5429), I have control over that.

But, yes, I think you and Andy are right: the answer is to have the donation commitment made at the sending end, and then there's little or no political benefit for my refusing the message.