Matt Nolan

What is a Gini?

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Everywhere we turn nowadays people are talking about Ginis.  And sadly, they are not misspelling Genie, they are talking about Gini coefficients.

The reason for this interest in Gini coefficient stems from the fact they are used to measure “inequality” in an income distribution – with books such as the Spirit Level made hay discussing the relationship between Gini coefficients and other social outcomes.

Now I’ve spent a bunch of time talking about the claims (eg for the Spirit Level directly I wrote this and this), but I’ve never written anything directly about the Gini coefficient.  There is a good reason for this, while I understand it is a measure of dispersion in a distribution I still had to (and still need to) learn things about the measure and other measures.

However, let me discuss what the Gini coefficient is – or at least one of a multitude of different ways we can view a Gini coefficient.

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Shamubeel Eaqub

Help! Census confusion

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I have been trying to figure out the latest census figures, especially for sources of population growth. Does anyone know what I am doing wrong?

I calculated the change in population using the post enumeration survey. I counted up the births and deaths from the vital statistics from Infoshare. The difference should be international net migration. In the 2001-2006 period there was a difference, but a small one.

In the latest census, the gap is really quite large. Implied net migration is around 500 people per year, compared to the data that is normally used for international migration (7,500 per year).

Does anyone know why the difference is suddenly so large? Or what I am doing wrong?

Also, sorry I have been missing in action from the blog. Work has been crazy and I was writing this book to, um, agitate people.

Population growth - between censuses

Matt Nolan

Discussion Tuesday

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Another video, same artist and all

There are few songs that illustrate the give an example of status good behaviour than “Mercedes Benz”

 

Infometrics

Can we justify the Easter trading laws?

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Back in April, Benje Patterson decided to have a think about whether the Easter trading laws really made sense (Infometrics link).  His view was that:

Having so far failed in my search for a reasonable justification for restricting Easter trading in New Zealand, my mind then turned to a more consumer-orientated motivation that transcends religion and worker welfare.  Perhaps I am the odd one out and the majority of society want the shops to be closed at Easter simply because it allows them to enjoy a quiet day, free of temptations to hit the shops and consume.

Is this the only fair justification – and is it a reasonable justification in of itself?

Matt Nolan

A response to Danyl on data and inequality

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Over at Dim Post I see Danyl is discussing the latest (2014) Household Income Report and Piketty’s book Capital in the 21st Century.  Excellent – there are lots of important and interesting issues to discussing look at these sources.

However, in this instance the data he is using and his interpretation is sadly a bit off.  I thought I’d discuss why this is here. Read more

Matt Nolan

Potential output in monetary policy

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When it comes to “potential output” there is often a view that the economies potential to produce is determined by the labour, land, and forms of capital that are available to create this output from – and this is right!  Furthermore, each of these factors tends to produce a diminishing amount of additional output as you use more of it.  Although the factors of production are often complementary this often implies a situation where – in the long-run – the potential for output (and growth in said output) in a nation is fundamentally about technological change and the quality of institutions.

However, in a recent speech by John McDermott of the RBNZ he points out that, when it come to considering monetary conditions, the type of “potential output” we are interested in is a bit different.

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