The economics of spam

Junk emails cost $20bn a year. Not just an irritation.

Here's a fascinating new paper (pdf) from the Journal of Economic Perspectives on the economics of spam, by Justin Rao and David Reiley:

The negative externalities imposed by spam include wasted time for consumers: both wading through irrelevant advertisements in one’s inbox and missing an important message that went to the junk mail folder. They also include the costs important message that went to the junk mail folder. They also include the costs of server hardware, which requires more than five times as much capacity as would be required in the absence of spam, as well as the costs of spam prevention services provided by firms to reduce the burden on users. . .

Taken together, the total costs of spam worldwide today appear to be approximately $20 billion, in round numbers.

The authors review literature on the revenue of spammers, and find that it's likely to be around $300m a year. In other words, spam destroys around $19.7bn dollars of value every year. The authors compare this to car theft, which imposes societal costs of around $10bn and brings revenues to the thieves of around $1bn; and to driving a car, which imposes societal costs of around five cents a mile and brings in average revenue of around 60 cents a mile.

Clearly all these numbers are extremely rough estimates, but if they are even in the same ballpark as the truth then it is clear that spam ought to be a public policy priority to a far greater extent than it actually is. Imagine if the number of car thefts doubled overnight; would people really question whether that calls for governmental involvement?

The problem the authors identify is one of negative externalities, similar to the issues raised by carbon emissions. So one would expect the solution to be analogous to the solution economists often call for to deal with externalities, which is a Pigovian tax - charging someone who harms society an amount equivalent to the damage they do. Unfortunately, as the authors show, such a measure is pretty much impossible when it comes to email spam. The spammers would obviously not co-operate, and every alternative involves trying to graft on some form of payment mechanism to email, which is a protocol incredibly unsuited technologically to any such addition.

Instead, the best thing to do is probably to hit the spammers where it hurts: their revenues.

One fruitful avenue is to put legal pressure on domestic banks that process payments from foreign banks known to act on behalf of spam merchants. This could put downward pressure on conversion rates and with them, proifts. Another proposal comes from our colleague Randall Lewis, who imagines “spamming the spammers” by identifying spam emails and placing fake orders on spam-advertised stores. This step would increase the merchants’ costs dramatically, as they would find it much more difficult to fullfil orders, and their banks may raise their fees if they submit many invalid payment authorization requests. Of course, an unintended consequence is that from time to time, a legitimate merchant will be inundated with bogus product orders.

Commenting on the paper, Digitopoly's Joshua Gans points out that, under US law, that may not be entirely legal:

A few years back I contacted Yahoo and Google with an idea to counter spammers. What if for each spam email that they picked up, they responded — perhaps entering details into phishing forms? This would overwhelm spammers and they would not be able to find ‘legitimate’ responses from the gullible few. That would really alter their returns. Unfortunately, it was explained to me that such a measure would constitute an attack by a US corporation and, apparently, that is against US law.

Spam may be here to stay, then. The real solutions are technological, and don't involve fixing email so much as abandoning it altogether; the time for being able to accept free, unsolicited email from anyone seems to be coming to an end. Those who are trying to build its replacement will be happy indeed to hear that.

The full paper is a surprisingly good read; if you're looking for something to flick through on an e-reader over the weekend, why not give it a go?

Spam, spam, spam, spam, spam, spam, spam, spam, lovely spam, wonderful spam. Photograph: Getty Images

Alex Hern is a technology reporter for the Guardian. He was formerly staff writer at the New Statesman. You should follow Alex on Twitter.

Ukip's Nigel Farage and Paul Nuttall. Photo: Getty
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Is the general election 2017 the end of Ukip?

Ukip led the way to Brexit, but now the party is on less than 10 per cent in the polls. 

Ukip could be finished. Ukip has only ever had two MPs, but it held an outside influence on politics: without it, we’d probably never have had the EU referendum. But Brexit has turned Ukip into a single-issue party without an issue. Ukip’s sole remaining MP, Douglas Carswell, left the party in March 2017, and told Sky News’ Adam Boulton that there was “no point” to the party anymore. 

Not everyone in Ukip has given up, though: Nigel Farage told Peston on Sunday that Ukip “will survive”, and current leader Paul Nuttall will be contesting a seat this year. But Ukip is standing in fewer constituencies than last time thanks to a shortage of both money and people. Who benefits if Ukip is finished? It’s likely to be the Tories. 

Is Ukip finished? 

What are Ukip's poll ratings?

Ukip’s poll ratings peaked in June 2016 at 16 per cent. Since the leave campaign’s success, that has steadily declined so that Ukip is going into the 2017 general election on 4 per cent, according to the latest polls. If the polls can be trusted, that’s a serious collapse.

Can Ukip get anymore MPs?

In the 2015 general election Ukip contested nearly every seat and got 13 per cent of the vote, making it the third biggest party (although is only returned one MP). Now Ukip is reportedly struggling to find candidates and could stand in as few as 100 seats. Ukip leader Paul Nuttall will stand in Boston and Skegness, but both ex-leader Nigel Farage and donor Arron Banks have ruled themselves out of running this time.

How many members does Ukip have?

Ukip’s membership declined from 45,994 at the 2015 general election to 39,000 in 2016. That’s a worrying sign for any political party, which relies on grassroots memberships to put in the campaigning legwork.

What does Ukip's decline mean for Labour and the Conservatives? 

The rise of Ukip took votes from both the Conservatives and Labour, with a nationalist message that appealed to disaffected voters from both right and left. But the decline of Ukip only seems to be helping the Conservatives. Stephen Bush has written about how in Wales voting Ukip seems to have been a gateway drug for traditional Labour voters who are now backing the mainstream right; so the voters Ukip took from the Conservatives are reverting to the Conservatives, and the ones they took from Labour are transferring to the Conservatives too.

Ukip might be finished as an electoral force, but its influence on the rest of British politics will be felt for many years yet. 

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