Why central bank models failed and how to repair them?

John Muellbauer of Oxford University has a piece which says things which we knew but conveniently forgot:
The failure of the New Keynesian dynamic stochastic general equilibrium models to capture interactions of finance and the real economy has been widely recognised since the Global Crisis. This column argues that the flaws in these models stem from unrealistic micro-foundations for household behaviour and from wrongly assuming that aggregate behaviour mimics a fully informed ‘representative agent’. Rather than ‘one-size-fits-all’ monetary and macroprudential policy, institutional differences between countries imply major differences for monetary policy transmission and policy.
To take into account all the feedbacks, a macroeconomic policy model needs to explain asset prices and the main components of household balance sheets, including debt and liquid assets. This is best done in a system of equations including consumption, in which shifts in credit conditions – which have system-wide consequences, sometimes interacting with other variables such as housing wealth – are extracted as a latent variable.7  The availability of home equity loans, which varies over time and between countries – hardly available in the US of the 1970s or in contemporary Germany, France or Japan – and the also the variable size of down-payments needed to obtain a mortgage, determine whether increases in house prices increase (US and UK) or reduce (Germany and Japan) aggregate consumer spending.  This is one of the findings of research I review in Muellbauer (2016).  Another important finding is that a rise in interest rates has different effects on aggregate consumer spending depending on the nature of household balance sheets.  Japan and Germany differ radically from the US and the UK, with far higher bank and saving deposits and lower household debt levels so that lower interest rates reduce consumer spending.  A crucial implication of these two findings is that monetary policy transmission via the household sector differs radically between countries – it is far more effective in the US and UK, and even counterproductive in Japan (see Muellbauer and Murata 2011).
I mean what can one even say to such issues?

Leave a Reply

Fill in your details below or click an icon to log in:

WordPress.com Logo

You are commenting using your WordPress.com account. Log Out / Change )

Twitter picture

You are commenting using your Twitter account. Log Out / Change )

Facebook photo

You are commenting using your Facebook account. Log Out / Change )

Google+ photo

You are commenting using your Google+ account. Log Out / Change )

Connecting to %s

%d bloggers like this: