Matt Nolan on the Top 10 economic principles to keep in mind

Today's Top 10 is a guest post from Matt Nolan, an economist at Infometrics, and an author at the blog site TVHE.

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The Brexit vote, with Leave voters disproportionately from disadvantaged areas, Donald Trump’s election in the United States based on a strong performance in the economically stagnant rust belt, and a growing concern about immigration and the labour market in New Zealand, have made it clear that there are economic issues people are understandably concerned about.  These changes have helped far more people than they have hurt – but the fact that some have lost out is very relevant to those people, and figuring out what policy should do in these circumstances matters.

However, in order to discuss these issues it is important to find some core economics concepts that allow us to understand them.  Instead, it appears that much of the debate has fallen for a number of fallacies – or missed significant issues – which economic logic can help us look through.  Only once we’ve done this can we reasonably discuss these issues and what can be done.

Most concerningly, the debate based on these fallacies has seen domestic residents in countries blame foreigners – both those onshore and offshore.  By discussing these ideas I hope to point out why such blame is unwarranted and leads us down the wrong path.

1. Lump of labour fallacy:  Work heading overseas

Often people act as if there are some fixed immutable number and type of jobs, as if they have been passed down from on high – this is called the Lump of Labour Fallacy.  As a result, when thinking about workers from outside New Zealand there is a view they are “taking jobs”.  However, we can see this view is flawed in two ways:

  • If someone moves here and “takes your job” they produce and in turn demand goods and services.  This creates demand for additional work – so jobs are created.  Furthermore they do not work alone, an issue we will discuss later.
  • If someone from overseas “takes your job” then that would free up your time for doing something else – as there is scarcity, there are always other things to be done.

By using this simple starting point we can start to tease out why there is not some fixed lump of jobs, and what issues people may be concerned about in the face of change.

The election of Trump in the US has, in part, come from the fact that a number of people in the Midwest felt that he understood what was going on with them better than the establishment did.  A mixture of technological change and globalisation saw the work many of these people once did get replaced either by machines or by workers overseas.

The lump of labour fallacy tells us that they would find other work.  And they did – generally lower paying work with less economic security.  New jobs were created, but these individuals still felt that they lost from the process.  This is an important part to keep in mind.  It does not have to be like this (as we discuss soon) – but there is potential for it, something policy makers have to be aware of.

Here believing new jobs wouldn’t be created was a fallacy – but the fact they have seen their prospects turn down has been ignored.  But before we can think about how to help, we still have a few issues to cover.

2. Lump of labour fallacy:  Immigrants taking jobs

Now in New Zealand the fear is more about people moving here to take work.  Unlike someone overseas producing what you would have, the argument that you end up worse off if someone moves here is much weaker.

Someone that moves to New Zealand is using the same technology as you, they have access to the same capital (at most), they have skills that New Zealand employers are less likely to recognise, and they face the same labour laws.  In other words there is no “unfair” advantage given to them.

So say they do move into a role in New Zealand.  They are also a consumer in New Zealand, purchasing products from the country.  As a result, they also increase demand for non-tradable products within New Zealand.

But say it is a role in your industry that was taken by someone from overseas, and say that you do not make a non-tradable product.  Well, I would also note here that workers aren’t just substitutes for each other.  In New Zealand, immigration authorities screen potential migrants for the skills they have, and bias approval towards workers they believe there is a “shortage” of.  In this context shortage doesn’t just mean there aren’t enough – but also that the labour of these workers boosts how productive other domestic workers are.

For example, you may work in an office – however, your role would have little to no value if it wasn’t for the IT team supporting your technology, the strategy team providing tasks for your team to complete for the firm, the sales team providing the final product to the client, and the HR team ensuring that important roles are filled.

Given this bias in immigrant approvals, it is likely that migrants are improving your job prospects rather than diminishing them!

An imperfect way of judging this is with wage data – and it has been the RBNZ’s interpretation of slow wage growth being partially due to net migration that has added fuel to the fire of the idea that migrants are somehow taking jobs.  However, they have noted themselves that it is the weaker labour market in Australia that is behind this dynamic – a factor that has held up unemployment rates in both countries implying Kiwis who are out of work no longer feel comfortable heading over the Tasman for work.

As a result, blaming arriving migrants – who in fact complement the skills of Kiwis and help create income for domestic residents – shows a misunderstanding of what is going on.  And is leading to distasteful policy suggestions.

3. Comparative advantage – how specialising on what we are “relatively good at” creates wealth

As nations, when workers and investors in individual countries concentrate on what they are “relatively good at”, this implies that more goods and services will be created – so allowing this to happen is a positive sum game.  The technical term for this is Comparative Advantage.

A focus on comparative advantage, and exposing domestic economies to the global market, has seen incomes rise sharply across the world – with the number of people facing absolute poverty falling sharply.

The concern is that people who have skills in a country making the product another country is “relatively good at” will lose out from such an arrangement.  Comparative advantage still holds, but we should be aware of these potential losers and spend some of the gains helping them improve their lot in life.  This is the US Midwest story.

This is made clear by looking at the “Great Reshuffle” in incomes that has occurred.

Bitterness about global trade isn’t focused on those it has lifted out of poverty, or the manufactured goods it has made increasingly affordable – but because, especially in the United States, it appears the gains from trade have fallen in the hands of a few while a large group of people have lost income and security from these changes.  Rather than being a critique of trade in general, this is a critique of corporatism – which takes us to the point that competition matters.

Note here though, that Trump’s suggestions do not look like a good solution for those groups.

4. Competition matters a lot

When Adam Smith wrote the Wealth of Nations it was not the call for unfettered free markets than many people assume.  Instead, among a large range of other things, it provided a compelling argument against state legislated monopolies. 

During the 18th Century, monopolies were seen as essential due to the large cost of investment involved, the innovation required, and also for the ability for monarchs to grant favour to whom they wished.  It was Adam Smith that discussed how spontaneous order stemming from those acting in their own self-interest could lead to a situation where resources are allocated to those who desire them most.

The most common reason given for why competition matters is a concept called “deadweight loss”.  Deadweight loss refers to the missed opportunity where buyers and sellers would be willing to trade at the current price, but don’t.  Here a self-interested firm knows that its decision to sell to someone will lower the price of their product, and so they do not sell. 

However, in actual markets the existence of tacit price discrimination (eg sales) often limits these losses IF the firm was some homogenous profit maximising entity – although in a manner that leads to excessive inequalities.  Instead it is incentives inside the organisation of the firm that are more significant, leading to a situation where managers and workers within a firm will exert some of the firms market power by simply doing less work and refusing to take on efficiency improving innovations.

Adding together all the ways that monopolies reduce efficiency suggests that inducing competition can have a large positive impact on economic outcomes – both increasing incomes and reducing inequality.

5. But information and risk matter too

However, competition is not the be all and end all.  Consumers without easily digestible information about what they are consuming can be taken advantage of.  Employers who do not know the quality of a given persons work will be reluctant to hire, especially in times of uncertainty.  People investing in skills can have a hard time deciding what to do if there isn’t some clarity about what life path that investment will take them down.

One thing I suspect that all economists, including myself, have underplayed is the level of uncertainty globalisation and technological change – in conjunction with an economic crisis – has created for individuals.  When starting a household or raising a family, certainty has a high value – and the last few years have made people feel uncertain. 

When the safety net was established the call was that “all men in all lands may live out their lives free from fear and want”, and although people exaggerate how much social security historically provided that in the past it is fair to ask whether we are meeting the public’s view about this principle now.

A key reason why people accept a relatively large government in modern democracies is because they believe government will help to insulate them from risk.  Evaluating this role – and whether expectations meet reality – is an issue everyone involved with economic policy making needs to face.

6. In the long run we’re all dead

The famous, and often misused, quote by Keynes “in the long run we’re all dead” provides a cutting criticism to many of those who are unwilling to listen to parts of the public disaffected by changes in the global economy.

If I had a dollar for every time I’ve been told that people/voters are “stupid” and that it is “obvious” that in the long run everyone will be better off I would have a reasonable chunk of change – I wouldn’t be rich, but I’d be comfortable.

The thing is, there is a transition that occurs – when economic conditions change significantly some people see the skills they have become very valuable, other people see their skills lose value.  For those who lose, they see their incomes and perceived self-worth decline.  Yes these costs are transitory – but given that, for some, that transition is their entire lives, it is still an incredibly relevant cost.

7. The broken window fallacy

Now surely the answer regarding how to help those who suffer from such transitional changes – give them a job guarantee!  By having society pay them to keep doing their job they do not lose their perceived self-worth or income.

Of course, in a world open to global competition, subsidising an industry (which is what this is) is unlikely to be allowed.  As a result, we could instead move people into government job schemes – not necessarily doing anything, but receiving a wage nonetheless.

To those with memories old enough this may sound familiar to the job schemes that existed in New Zealand up until the mid-1980s.  Such schemes were extremely costly for the taxpayer, reduced the transition of people into work where their skills did have use, arbitrarily ensured that otherwise identical people doing the same work had different incomes, and also made the unemployment statistics look a lot better than they actually were.

In the end these schemes were indicative of something called the broken window fallacy.  Here we see the income paid to these people, but what is unseen is that we are paying people to waste their own time – sacrificing time they could have used to gain something of value (to build skills or do something they enjoy) to produce nothing, and sacrificing the other things this income could have been spent on (eg new roads).

This is often noted as a critique of Keynesian economics – but that is a little unfair on Keynes.  The situation he described where you would employ people to do nothing was very temporary and related to a messy breakdown in the spontaneous order we discussed above.  He would not have supported the idea of long lasting jobs of no value – instead he expected that we would all be working shorter hours and enjoying more leisure time.

Now this is not to say that active labour market policies (which include government mandated work) don’t have some role – but the evidence on such schemes is mixed and the key messages are that they must be designed carefully and that even then their effectiveness is uncertain in a changing world.  Furthermore, insofar as such schemes subsidise the employment of those who are out of work they may – in turn – reduce wages for those who are employed in similar roles.

8. Incentives matter – why individual liberty is important

For all the empathy we may feel for those who see their job roles become less valuable due to technological change and open markets, let us not treat these people like children.

If this happens to my role – which is imaginable – I would hardly want to be treated like a victim.  Instead I would demand an opportunity to try to show I can do something and do it well.  If all we do is talk about income support and how sorry we feel all we are doing is demeaning people in our society.

Furthermore, the fact is that technological change and globalisation are helping many people, including the very worst off in the world.  The final outcome of such change is where we should want the world to move – not where we should be hiding from.

As a result, although we should help each other with any such transition – we also have to take some responsibility for the choices we make in our own lives about how to insure ourselves against such change.  Job insurance, saving, investing in skills – these are all pro-active steps we can take to make sure that we benefit from these changes.

From what I can tell, many people believe that it is unjust that they have to face these risks when they don’t believe that the post war generation had to.  And this is a view I can understand – although we need to ask whether it is true, or whether governments simply pretend they can do more to protect us than they really can.

However, if we do view matters that way, then having government support those willing to make the transition – subsidising education, offering a safety net that incentivising developing skills and engagement to the labour market, pooling insurance – are all ideas that can be justified.  But we do already implement all these policies; the question is instead whether we do enough.

But none of this suggests taking away the incentive for individuals to change as the world changes.

9. Prices represent scarcity

So what is the main way people get an idea of what training to do and what occupation they should move towards.  Wages.

No matter how much people enjoy complaining that it is unfair a certain person is paid more than them, it is generally the case that relative wage rates represent how scarce that type of employee is.

If, after the Global Financial Crisis, 100,000 New Zealanders went out and worked on a post-graduate economics education then the flood of new economics graduates would reduce my wage – or since many of them would simply be better economists, I would likely be forced to move into a different industry.

Now you may point out that undertaking such an economics education is expensive and difficult – and when people have to look after families, and have different interests, this is unlikely.  And I would agree – this is the crux of the issue.

If people have different interests, then we need a higher wage to incentivise people training to do the job.  If people have a family and so are unable to find the time to train, then we have to ask whether the opportunity society has provided people is seen as fair.

If the outside option people have from a certain job is very bad (eg either work for me or starve to death) there is a power imbalance – those people are being taken advantage of.  The low wage still shows that there isn’t much scarcity, but the low level of scarcity is due to a group of workers not having much choice.  By introducing policies that redress this (eg paying the benefit while training, increasing the weekly payment on the benefit) we deal with this – but in order to justify that we need to have the conversation about what we think is fair.

10. As long as scarcity exists, economic principles matter

If we lived in a society where we were plugged into VR machines that filled our every desire, while machines kept us fed and alive, we’d be in some form of the Matrix – but we would also be in a post-scarcity society.

However, such as society doesn’t exist – and even in a situation where all our material needs and every conceivable material want is available due to technological change, without subtracting from natural capital, our social and other psychic needs and desires will remain unsatiated.

As long as there is some scarcity, the economic principles regarding the availability of jobs, comparative advantage, and the role of government in providing opportunity will remain pertinent.

What has occurred with the global economy and technology is a positive sum game – not a zero-sum game.  There is no need to reverse progress to help those who may have lost out – but keeping these principles in mind we enjoy the gains from progress while helping to give a hand up to those who feel left behind.

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Regarding #1...2 ...3

A boat building business in NZ, which had been in business for 30 yrs decided to close down in NZ .
It decided to "give" its' intellectual property to a Chinese manufacturer , and simply import the boats..

It was now able to import the same boats and sell them much more cheaply.... and the result was that other local boat manufacturers were forced to do the same... ( compliance and labour costs in NZ make it very difficult to compete)..
A generation of boat building experience is disappearing..??

Within the context of comparative advantage, and "lump of labour fallacy"... how does this example fit in..??

This is the problem with economists. They have the luxury of peering down at the teeming masses from atop their ivory towers. They privilege generalities over specifics.

What does it matter to the Kiwi workers who can't find a job in a small provincial town because of all the back packers prepared to accept abysmal pay and working conditions, if some new jobs are created in the local backpacer hostel or supermarket, when likely as not those positions are also filled by other backpackers? Let alone when big honey processors bringing hives and Filipino "beekeepers" to take care of them and harvest the honey, leaving out local people entirely.

#4 and 5.... Adam Smiths idea of the "invisible hand" and Hayeks'.... idea of the "telecommunications" nature of market prices.... are not perfect..

Free Markets are not perfect..... they can't respond to what is the "greater good"

A great example is the environment... and the environmental costs that may happen in producing goods.

I'm reading a really interesting book at the moment... Touches on much of what Matt is writing here..

"How mkts fail"... John Cassidy

Free Markets are not perfect..... they can't respond to what is the "greater good"
If the greater/common good was a real, definable, inherrent goal amongst participants, the free market would intrinsically cater to it. The free market has much more capacity to cater to the common good than any political measures ever could.

"A great example is the environment... and the environmental costs that may happen in producing goods."
Again, the market perfectly caters to this. Hence why we have linear/non linear/increasing/decreasing forward price curves.
Any political interaction could never perfectly allocate environmental costs as well as a completely free market.

If the greater/common good was a real, definable, inherrent goal amongst participants, the free market would intrinsically cater to it.

Thats right , the free mkt might cater for such things.... BUT... there are things that are not inherent goals amongst participants ,,.. ( as u put it ).... and which are very important to society and also future Generations of people..

Please explain how the free market properly prices , for example, over fishing that leads to a complete depletion of a fishery..???? ( both the individual fisherman and the individual consumer want as much fishing as they can ) Why are fisheries regulated..????

the "greater good" is a metaphor for what lies beyond the self interest of individuals... ( is more important to communities as a whole )

Same with National Parks.... Common sense shows to me that they are a good thing... for future generations as much as for us..
Explain how on earth the "free Market" could ever do this..???

The greater good is not a "goal".... it is part of the dichotomy that lies between the individual vs the community/collective/society...etc.

Free market principles are pretty amazing....BUT... it is definitely not the end all.

"Please explain how the free market properly prices , for example, over fishing that leads to a complete depletion of a fishery..????"
There is no property market in western culture that I would consider to be a free market.
In terms of natural resource depletion, given a society with a common goal, this would naturally be inter-temporally allocated efficiently.
Do no confuse optimal markets and greed. If anything, regulation in these aspects accentuates the inefficient allocation and over fishing. Would we have over fishing if everyone had the same rules? No, because there would be no incentive to take more than your neighbour if you knew that the marginal value of that extra fish is decreasing as your effective costs are increasing.

I do see your point with National Parks, etc. However, these transcend the nature of normal goods and services. As such, a public body would be best to administer these - something that is not mutually exclusive to free market ideology. I can't think of any economist who has advocated for absolutely no government, and it is for this reason.

given a society with a common goal, this would naturally be inter-temporally allocated efficiently.

Thats my point... it requires society to do this... the free market, itself , can't... Society makes and enforces those rules.

A free market is simply a large number of individuals doing transactions, in their own self interest . In that environment price is the information transmitter that allows the "invisible hand" to do its thing.. In this context, it is highly efficient in allocating resources...etc

The price of fish in the shop does not reflect the state or health of the fishery resource that it comes from....
( it only reflects the supply/demand dynamics.)
The same thing applies to the idea of manmade climate change...

Common sense shows that the Free Market works fine .... but not for all things.

Also... in the real world Greed is one of the human qualities that make regulation a very important thing..
And even with regulation there are plenty of people who don't play by the rules and don't care..
( As far as I know, there are enuf people out there that are driven by short term incentives, even in the knowledge of the long term consequences, that they can cause damage)

There will always be someone who will take more fish while knowing they are increasing the effective cost because the fishery is dying...
I don't see how regulation can possibly accentuate over fishing.???

"Thats my point... it requires society to do this... the free market, itself , can't... Society makes and enforces those rules."
By its fundamental nature, the free market does.

And, you even agree;
"A free market is simply a large number of individuals doing transactions, in their own self interest . In that environment price is the information transmitter that allows the "invisible hand" to do its thing.. In this context, it is highly efficient in allocating resources...etc"
So, why can't it optimally set intertemporal allocations?

"There will always be someone who will take more fish while knowing they are increasing the effective cost because the fishery is dying.."
Your logic is wrong, there. Hence why you cannot understand my argument..

So, why can't it optimally set intertemporal allocations?

I cant think of any examples where it does...????

Do you think the tobacco industry along with the smokers themselves changed the popular culture of smoking..????
Why do smokers smoke if they are aware of the longer term cost of their smoking..???
Who pays for those longer term costs..??
did all the important information come from within the "market" itsself..??
What were the agencies involved in changing peoples attitudes to smoking,...???

The way i see it... there is a kind of symbiosis between the self interest of the individual vs the collective interests of a society....

I think I do get your argument..... essentially u are suggesting that a pure , optimal Free market address all issues in the most efficient way..
My argument is.... yes...but not always..

Markets, as a human construction, are quite good at some things. But like all human creations, they are incomplete, partial creations.

And their incomplete nature makes them very useful tools for hiding things.

I think globalisation and immigration are too often blamed for a lack of low skill jobs when it is actually technology at 'fault'. Even if cars were built in the US I'm sure they would be looking at using robots instead of labour unless labour was incredibly cheap.

Yup. Those jobs aren't coming back. Premature deindustrialisation is not talked about enough.

I would argue the problem is a lack of education. There will probably be plenty of jobs for those prepared to upskill themselves.

And often the required level of education/experience in job advertisements is absurd, a cop out by the employer. For example; why would a DOC field worker need a BA or X years tertiary. I would have thought that a love for and knowledge of our natural environment would be all the qualification needed.

Inflated application credentials? - to cover the butt of the recruiter if the hire doesn't produce the goods.

I'd rather see callouses on the palm of their hand than hair

Oh I completely agree. In case it was not clear, by "those jobs", I primarily meant manufacturing.

Unfortunately education is increasingly out of reach for many, especially in the US. And it is not just tertiary that matters; early childhood education is going to matter more and more.

Hey JJ. Since when does every job require a degree in something.
Look at the Auckland Herald this morning with the plight of degree educated cafe staff on zero hour or day to employment via the labour hire industry.

You say lack of education.
I say lack of useful policy.
Hey lets say lack of education of the policy makers.
Happy to agree, now.

No Jimbo, no there won't.

Lowest-common-denominator algorithms will gut the educated middle class in the same way that automation has gutted the skilled working class.

Welcome to your as a dog-groomer or car washer or yard-sweeper.

I am not convinced it's automation that is gutting employment and incomes. I see that it is the actions of those who have gained a stranglehold on ownership of the money flows and ownership full stop.
With decent policy automation should lead us all to abundant and relaxed lifestyles.

Done right and used properly technology and mechanization could assist us as we depopulate the planet, it can replace the need to have more and more people to provide for elders, which if you look at it for what it is, is a pretty silly reason to ruin a planet. The problem is it will be used to mazimise profit for a few, instead of using if for the benefit of everyone.


America has been de-industrializing for years now , its just about to reach a tipping point as more high-tech and sophisticated service sector jobs are about to be exported to Asia .

American hegemony in industry is history , they simply allowed and even encouraged their prosperity to be exported to low -wage economies , resulting in local unemployed folk living in poverty, unable to pay the electricity bill and keeping themselves from depression and hopelessness by sniffing , snorting , smoking or injecting themselves with opiates .

Regrettably , Trump will be unlikely to stop this trend , unless he resorts to protectionist policies to stop the rot that goes with an Empire in decline.

I wish him well , because the alternative to a robust and strong America is just too ghastly to contemplate .

Well said Boatman. The western democracies are under existential threat and the consequences of failure are ghastly,as you say. The prospect of the Muslims or Chinese or Indians or Africans in charge doesn't bear thinking about and its nothing to do with race. Perhaps we need to remind ourselves how vital the factors that make western democracy so successful for most are: Universal education, individual property rights, habeas corpus and general civil rights, the limited liability company, personal freedom and the right to vote etc. - and why folk from the above areas will crawl over broken glass to live as we do.
The decline of social mobility and a tendency by the elites (left and right) to Ignore a huge section of our community (the working poor) is highly corrosive and potentially destructive of the whole as are high levels of low skilled immigration. Trump is planning on deporting the illegal immigrants as should have been done years ago. They have no legal right to be there; go home or apply for immigration like everyone else.
What's going on in western Europe with these so called refugees is an even bigger mess. There are millions with a very high percentage of single young men with little education, no job prospects and a medieval attitude to women amongst other issues. There is now a rape and sexual assault epidemic being committed against the young women and boys of Europe. I'm sure that will go down well among the skinheads and right wing extremists over there. An unfolding nightmare!

More improved productivity than de-industrialising. Jobs wise for Trump that is the tricky one to solve. Though if he opens up more federal land to oil and gas exploration the US will have a huge energy cost advantage over their competitors.

"Since 1987, US manufacturers have increased their output by 80 percent at the same time as they have reduced their workforce by about 17 percent. In other words, American factories are about twice as efficient today as they were three decades ago. So we're producing more and more stuff, even as we use fewer and fewer people to do it."

I think that many voters are past listening to spin or for that matter reason. They are only judging things by results, how they are affected and are obviously prepared to shake thinks up and wreck them until they get what they want.

And what doesn't seem to be getting through to the "educated" is that the many voters are now the biggest proportion as evidenced by Brexit and Trump. No amount of spin is going to improve their lot and when you have nothing to lose those who do have the lot need to watch their asses.
The two main fallacies put on these voters in most of the spin are, they are uneducated and in the minority. Bollocks.

A shame this paper wasn't wasn't published 20 years ago. "Antarctic sea ice had barely changed from where it was 100 years ago, scientists have discovered, after poring over the logbooks of great polar explorers such as Robert Falcon Scott and Ernest Shackleton.

Experts were concerned that ice at the South Pole had declined significantly since the 1950s, which they feared was driven by man-made climate change.

But new analysis suggests that conditions are now virtually identical to when the Terra Nova and Endurance sailed to the continent in the early 1900s, indicating that declines are part of a natural cycle and not the result of global warming.

It also explains why sea ice levels in the South Pole have begun to rise again in recent years, a trend which has left climate scientists scratching their heads."

Don't worry Profile, at the other end of the planet Arctic ice has just set a record low for October.

"Record" since 1981... Why didn't they start the record at the start of the satellite era in the early 1970's - like the IPCC used to? But much more scary if you start your chart at the high point. Surely the Cryrosphere paper highlights the hype about polar ice and the complete lack of historic analysis.

Should I be worried about the rampant SMB growth in Greenland at the moment?

“Especially importantly, satellite observations have been used to map sea-ice extent routinely since the early 1970s. The American Navy Joint Ice Center has produced weekly charts which have been digitised by NOAA.These data are summarized in Figure 7.20 which is based on analyses carried out on a 1° latitude x 2.5°longitude grid. Sea-ice is defined to be present when its concentration exceeds 10% (Ropelewski,1983). Since about 1976 the areal extent of sea-ice in the Northern Hemisphere has varied about a constant climatological level but in 1972-1975 sea-ice extent was significantly less.”

I'm not worried, it's all part of the 'natural long-term cycle', much like the current carbon dioxide levels are.

The antarctic sea ice is a very small part of its total (the vast bulk being on solid land) and only accumulates where the high winds and seas can't break it up to circle the globe. Not a good indication of temperature change.

Possibly is a good indicator of 'temperature change" - satellite data shows the Antarctic has cooled/flat lined since 1980. Global warming hasn't reached there yet.

I think most New Zealanders prefer to live in a country where there is only 4 - 5 million people. That's it! They don't want all these other people shifting here. Nothing to do with finances or race. Just their own lifestyles in mind.

Economics is a descriptive science, more akin to botany than to genetic engineering.

It's probably about two or three centuries away from being useful in the way that this article suggests.

But that shouldn't prevent the little b*ggers from amusing us. Go the economists!