How do things compare economically and financially between both parts of this island?

The narrative used to run along the lines of the economic challenges in the Republic

versus the relative prosperity of the North,

which enjoyed generous intervention from the UK taxpayer,

delivering all manner of benefits from a well-oiled national health service

to ample public sector employment

and subsidised education opportunities. That version of events is now being challenged. But it's a

complex issue and it's almost impossible to be definitive about how things stack up now or how

they might in a new political dispensation however many years down the line.

So in this week's Red Lines, we're at least going to try to open up the conversation.

And with me to do that are Economics and Business editor John Campbell, the Irish Times columnist Justine McCarthy, and Virgin Media's economics correspondent Paul Colgan. Welcome to all of you and thanks for joining us on Red Lines today. John, first of all, just help me to frame this conversation before we get into it any further. What are the issues you think we need to be considering when we're trying to compare things as they stand, North and South?

Well, cross-country economic comparisons aren't always easy.

You can have different systems.

You can have things measured in different ways.

And I think the really big thing to keep in mind about cross-country comparisons is you have to equalise for different price levels.

So in other words, you're asking, how much do I get

if I spend a euro in Dublin versus how much I would get if I was to try and spend that same

euro in Belfast? How much buying for my buck? Now, there are ways of doing this. There is a tool

economists use known as purchasing price parity. So that's where they attempt to equalise across

different economies for the different price levels that creates something called PPP dollars,

which we can then compare like with like. And happily, there is some work which has been done,

is being done in this area to help us give these like-but-like comparisons.

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