Wage stagnation in the US: more than meets the eye

If you can, always look below the surface of data.

Via the Economist journalist Daniel Knowles comes a good example of why its important to look below the surface of statistics. American economist Steve Landsburg addresses a commonly heard refrain – that the wage of the median worker has barely risen in the past thirty years – and shows that all is not as it seems.

Landsburg cites a book by economist Edward Conard (first chapter, containing what we're talking about, here), which itself cites the Census Bureau. I confess that, without a more specific citation, I can't find the exact data Conard uses, but have found similar enough data (pdf, table A-5) to confirm the overall thrust of the argument.

Conard shows that from 1980 to 2005, median income in the US rose just 3 per cent once inflation is taken into account, from $25,000 to $25,700. 2005 is pre-crash, as well, so this isn't a tale of the recession.

But when you break the data down by race and gender, a very different story appears:

  1980 Median 2005 Median Increase
All Workers 25,000 25,700 3%
White Men 30,700 35,200 15%
Nonwhite Men 19,300 22,300 16%
White Women 11,200 19,600 75%
Nonwhite Women 10,200 16,500 62%

For every single demographic group, there was a much bigger increase in the median wage than we see when the groups are combined. The reason for this is obvious when it's pointed out: demographic change in the US means that there are far more (low-salaried) women and people of colour working now than there were in 2005, which pushes the overall average down.

Landsburg illustrates it with a farmyard analogy:

Imagine a farmer with a few 100-pound goats and a bunch of 1000-pound cows. His median animal weighs 1000 pounds. A few years later, he’s acquired a whole lot more goats, all of which have grown to 200 pounds, while his cows have all grown to 2000. Now his median animal weighs 200 pounds.

A very silly person could point out to this farmer that his median animal seems to be a lot scrawnier these days. The farmer might well reply that both his goats and his cows seem to be doing just fine, at least relative to where they were.

This is almost an example of Simpson's Paradox, a well-known (to stats nerds) effect where the direction of a correlation disappears when that correlation is disaggregated. I was taught it with an example involving racial discrepancies in application of the death penalty:

Sixty per cent of white murderers are executed for their crimes, and fifty per cent of black murderers. Are black people discriminated against in the application of the death penalty?

Now suppose that we break down the murder victims by race as well. We find the common pattern that people tend to attack victims of their own race:

Number of murders where death penalty is applied

White Murderer Black Murderer
White Victim 50/70=71% 25/30=83%
Black Victim 10/30=33% 25/70=36%

What about now? Does it begin to look like black people are discriminated against? In this example, black people are more likely to be executed for the murder of black or white victims; but because the murder of black victims isn't taken as seriously by the courts, the fact that murderers predominantly attack people of their race makes it look like black people are less likely to be executed than white people.

The median income example isn't quite a case of Simpson's Paradox, because there is still a positive increase in wage whether or not the statistics are disaggregated. But it's still an example of a time when it is best to dig beneath the surface.

But there is more to be said on the story of wage stagnation. Because a second claim normally accompanies the belief that US wages have stagnated, and that is that there has been a "decoupling" of wages. Due to rising inequality, the median household wage hasn't risen as fast as the mean wage:

If we've seen that the median wage grows faster when disaggregated, then the solid red line is likely to take a steeper ascent. But what happens to the dashed red line when disaggregated?

Sadly, I cannot find the data required to answer the question. If anyone knows where to look, tell me, and maybe we can put the issue to rest.

An immigrant worker protests in Orlando, Florida. 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.

Nicola Sturgeon. Photo: Getty
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For the first time in decades, there is genuine dissent in Scottish Nationalist ranks

The First Minister is facing pressure to talk less about independence - and bring on new talent in her party.

She so recently seemed all-powerful, licensed to reign for as long as she chose, with the authority to pursue the return of our national sovereignty. We would then have the ability to strike our own deals on our own terms, a smaller, smarter, leaner nation freed from the stifling constraints of partnership with a much larger neighbour. There was, she repeatedly told us, nothing to be afraid of.

Now, suddenly, she is the victim of her own miscalculation: having misread the public mood, having raced too far ahead of moderate opinion, she finds herself at bay. The voters have delivered a public humiliation, while an opposition party until recently lampooned as unelectable is on the march. There is, suddenly, talk of her departure sooner rather than later.

Yes, this is a tough time to be Nicola Sturgeon…

Let’s not overstate it. The position of Scotland’s First Minister is considerably more secure than that of the UK’s Prime Minister. Theresa May wants out as soon as is feasible; Sturgeon, one suspects, will have to be dragged from Bute House. Sturgeon retains enough respect among the public and support among her colleagues to plough on for now. Nevertheless, things are not what they were before the general election and are unlikely ever to return to that happy state.

It’s all because of Scexit, of course. Sturgeon’s unseemly sprint for the indy finishing line left enough Scottish voters feeling… what? Mistreated, taken for granted, rushed, patronised, bullied… so much so that they effectively used June 8 to deliver a second No vote. With the idea of another referendum hanging around like a bad headache, the electorate decided to stage an intervention. In just two years, Sturgeon lost 40 per cent of her Westminster seats and displaced half a million votes. One could almost argue that, by comparison, Theresa May did relatively well.

For the first time in decades, there is genuine dissent in Nationalist ranks. Tommy Sheppard, a former Labour Party official who is now an influential left-wing SNP MP, published an article immediately after the general election calling on the First Minister to ‘park’ a second referendum until the Brexit negotiations are complete. There are others who believe the party should rediscover its talent for the long game: accept the public mood is unlikely to change much before the 2021 devolved elections, at which point, even if the Nats remain the single largest party, Holyrood might find itself with a unionist majority; concentrate on improving the public services, show what might be done with all the powers of an independent nation, and wait patiently until the numbers change.

There are others – not many, but some – who would go further. They believe that Sturgeon should take responsibility for the election result, and should be looking to hand over to a new generation before 2021. The old guard has had its shot and its time: a party with veterans such as Sturgeon, John Swinney and Mike Russell in the key jobs looks too much like it did 20 years ago. Even the new Westminster leader, Ian Blackford, has been on the scene for donkey’s. There are more who believe that the iron grip the First Minister and her husband, SNP chief executive Peter Murrell, have on the party is unhealthy – that Murrell should carry the can for the loss of 21 MPs, and that he certainly would have done so if he weren’t married to the boss.

The most likely outcome, given what we know about the First Minister’s nature, is that she will choose something like the Sheppard route: talk less about independence for the next 18 months, see what the Brexit deal looks like, keep an eye on the polls and if they seem favourable go for a referendum in autumn 2019. The question is, can a wearied and increasingly cynical public be won round by then? Will people be willing to pile risk upon risk?

As the hot takes about Jeremy Corbyn’s surprise election performance continue to flood in, there has been a lot of attention given to the role played by young Britons. The issues of intergenerational unfairness, prolonged austerity and hard Brexit, coupled with Corbyn’s optimistic campaigning style, saw a sharp rise in turnout among that demographic. Here, Scotland has been ahead of the curve. In the 2014 referendum, the Yes campaign and its can-do spirit of positivity inspired huge enthusiasm among younger Scots. Indeed, only a large and slightly panicked defensive response from over-65s saved the union.

That brush with calamity seems to have been close enough for many people: many of the seats taken from the Nats by the Scottish Tories at the general election were rural, well-to-do and relatively elderly. The modern electorate is a fickle thing, but it remains rational. The Corbynites, amid their plans for total world domination and their ongoing festival of revenge, might bear that in mind.

Chris Deerin is the New Statesman's contributing editor (Scotland). 

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