Title: Conference on Macroeconomics of Housing Markets
1Conference on Macroeconomics of Housing Markets
- Comments on the Papers of session 1 A
- By Gilles Dufrénot (University of Aix-Marseille
and Banque de France)
2Plan of the discussion
- Le cours sarticule autour de trois points
- I.-GENERAL COMMENTS
- ?The questions, the methodology and the main
results - Still unsolved puzzles (!)
- II.-SPECIFIC COMMENTS (methodological aspects)
- Paper by Bulligan
- Paper by Alvarez and Cabrero
- Paper by Ferrara and Vigna
3GENERAL COMMENTS
- Le cours sarticule autour de trois points
- Why the  agnostic approach leaves us with
unsolved puzzles
4What are we interested in?
- Le cours sarticule autour de trois points
- Three important goals
- Assess the vulnerability of the economy to
Housing markets (Hence the importance of finding
cross correlations) - Try to identify the main channels of transmission
of the shocks from the housing sector to the
economy (hence the importance of using several
indicators of the housing activity) - Prospective approach find leads and lags
dynamics to say whether housing variables can be
chosen as advanced indicators of the GDP
5How can we do that?
- Theoretical models typically Dynamic
Stochastic General Equilibrium models ? growing
literature (appropriate to study how productivity
shocks, technological shocks, monetary shocks,
etc affect the agents decisions of investment
in the housing sectors and the impact on the GDP - Statistical models ( agnostic about the main
transmission channels) ? only want to detect
correlations, leads and lags dynamics, common
factors in the series
6The three papers adopt the second approach (1)
- 1.- Country-specific studies based on time series
- The paper by Bulligan deals with the case of
Italy and use a structural VAR framework to study
the effects of monetary policy shocks ? Whats
new the sign restriction approach in the
long-run matrix to define the sequance of shocks - The paper by Alvarez and Cabreo deals with the
case of Spain ? Whats new butterwoth filters
to study the cross correlation between variables
of the housing sector and macroeconomic variables
7The three papers adopt the second approach (2)
- 1.- Country-specific studies based on time series
- The paper by Ferrara and Vigna deals with the
case of France. - Whats new The second part of the paper (!)
that discusses the long-run cross correlations
betwwen the housing markets and the economic
variables this allows them to explain why France
was less affected by the sharp decrease in the
housing prices
8The three papers adopt the second approach (3)
- 2.- All three papers yields similar conclusions
- The find strong correlations between the
business cycle and the cycle of the housing
activity (whichever variables are used to capture
the dynamics in either sector or the other) - They conclude that the activity in the housing
sector can be considered as a leading indicator
of the business cycles.
9First unsolved puzzle (1)
- 1.- What about the house price gap ?
- Which variables were at play during the last 10
years to explain the booming in the housing
investment and the upward price trend? - Fundamental variables growth of disposable
income per capita, long-term and short-term
interest rates, inward immigration flows (Spain),
credit growth, changes in equity prices, etc.. - Non-fundamental variables ( of increase in the
housing prices , not explained by the
fundamentals)
10First unsolved puzzle (2)
11First unsolved puzzle (3)
- If non-fundamentals are at play during the booms,
then we can expect a sharp correction when the
prices and activity in the housing sector
decline. - So, during upwards, when the house price are
over-valued, we expect to find a weaker
correlation with the GDP (because you have a
bubble)
12First unsolved puzzle (4)
- Now, when the bubbles burst, there are two
indications - Firstly, they do so when some macroeconomic
fundamentals begin to deteriorate (income,
unemployment, credit conditions, etc. ? In this
case the GDP growth may be a leading indicator of
the activity in the housing sector (!) - Secondly, deteriorating macroeconomic conditions
are the source of downward revisions in
expectations ? Stronger correlations betweeen the
GDP and the activity in the housing sector
13First unsolved puzzle (5)
- Implications for the time series-based approaches
- Selection bias if the period includes episodes of
huge price decrease (may explain the strong
positive correlations that are found) - Concerning the lead and lags effects the
approaches do not handle the house price gap
14Second unsolved puzzle (1)
- Spurious short-term cross-correlation ?
- Except in Spain and Ireland, the residential
investment does not account for a large share of
the economies. - Ratio of housing construction in of GDP 6,5
for the advanced economies and over the past 3
decades 5. - Accordingly, for the correlation between the
housing sector and the GDP to be strong, there
must be large corrections in the housing
construction!!
15Second unsolved puzzle (2)
- Two consequences for the time series models
- Again a problem of selection bias the
correlation found include periods of huge
-downward - corrections in the samples - Choice of the variables even if we accept the
idea that the housing sector activity leads the
GDP, the variable of interest should be the
investment rate in this sector (real residential
investment to GDP)
16Third unsolved puzzle
- The papers focus too much on the short-term, but
the long-run correlation may also be important - The papers argue that cyclical componenst of the
housing variables affect the cyclical upturns and
downturns of the GDP. - However, for downturns in the GDP, it is known
that they occur in the industrialized countries
when the ratio of housing investment to GDP
evolve below its historical trend ! - ? This implies that the trend components of the
housing variables affect the cyclical components
of the GDP
17SPECIFIC COMMENTS
- Le cours sarticule autour de trois points
- Paper by Guido Bulligan
18Cyclical andtrend growth analyses
- Business approach
- The old methodology by Burns and Mitchell has
been updated by Harding and Pagan (2002), Journal
of Monetary Economics ? link between the turning
points and the moments of the series cycles are
obtained as regards their contribution to
volatility, trend growth, correlation and
non-linear effects. - Missing nonlinearities in the series structural
breaks - ? Use non-parametric filters such as polyspectra
(bispectraum, trispectrum) evolutionary
sprectrum
19VAR models (1)
- VAR analysis to study the implication of monetary
policy shocks - Isnt there a problem of  multiscale housing
markets are characterized by long cycles with a
persitent dynamics, as compared with the other
macroeconomic variables in the VAR? Is it
possible to estimate the effects of a shock by
considering a VECM? -
- There is a similar study as yours done by Carlos
Vargas-Silva (2009) for the US (forthcoming in
the Journal of Macroeconomics), showing that
20VAR models (2)
- VAR analysis to study the implication of monetary
policy shocks - 1/ the magnitude of monetary shocks on the
housing markets is very dependent on the
selection of the horizon for which the
restrictions hold in the VAR - 2/ as compared with classical choleschi
decomposition ,, the impact of monetary policy on
the housing market is much less certain with the
sign restriction approach. - Do you find similar things for Italy?
21SPECIFIC COMMENTS
- Le cours sarticule autour de trois points
- Paper by Luis Alvarez and Alberto Cabrero
22Filters(1)
- There is one filter that may overperform the ones
described wavelet for several reasons
(simultaneous description of the high frequency
and low-frequency components) - Compared with the butterworth filter, you do not
need to eliminate some  high or  lowÂ
frequencies, because the filter is  multiscale - Compared with the Kernel regression, Wavelet
decomposition is also non-parametric, but the
analysis is done in the  frequency domainÂ
which is more appropriate for the study of
business cycles then time domain methodologies
23Comparison with DSGE models (1)
- One problem your empirical results sometimes
contradict the theoretical findings. - But, it does not mean that the DSGE models are
wrong! - The negative or positive response to shocks
depends upon - 1/ the interval of variation of the parameters
that serve to calivrate the models and - 2/ upon the nature of the technological,
productivity, monetary shocks. - How can you use your time-series based filters to
see whether your findings do indeed contradict
the conclusions of the models?
24Comparison with DSGE models (2)
- Three steps (Monte Carlo)
- 1/ obtain simulated series from the DSGE models,
for a given set of calibrated parameters - 2/ Apply the Butterworth and Kernel filters . Do
this a number of times (example 1000 times)
because, the effects of shocks may be nonlinear,
you must look at the Generalized impulse response
functions (GIRF) - 3/ Compare the population of cross-correlations
between the housing/residential investment and
GDP with the cross-correlation you find when
using the statistical data.
25Alternative methodologies for asymmetry
- Problem with the measures of brevity, violence,
steepness you do not know which variables are
at play to account for the observed assymetries
(credit constraints? Capacity constraints, labour
markets ?). - Alternative models including transition variables
- Deterministic models such as TAR or STAR models
- Stochastic models such as Markov Switching models
with endogenous probability of transition.
26SPECIFIC COMMENTS
- Le cours sarticule autour de trois points
- Paper by Laurent Ferrara and Olivier Vigna
27Choice of the 2-step version of the HP filter
- Motivation why using this filter if other
filters yield similar turning points? Are there
any robustness study elsewhere in the literature?
- One question to which extend can we say that
turning point in the housing sector are causing
those observed in the GDP? May be we are simply
detecting common factors - Something original the use of Confidence
indicator in the building sector (perception of
the activity by the housing industrials) ?
capture the supply side of the housing market
28Long-run analysis (1)
- Most interesting part of the paper, but no
rigourous statistical analysis to test the
arguments. This seems a promising area of
research because it relies on the fundamentals of
then housing markets - The conclusions challenges those of the IMF.
While the authors argue that the movements in the
housing prices and investment were smaller in
magnitude as compared with the other european
countries (Spain, the UK, Ireland), the IMF finds
that France was among the countries with highest
overvalued house price (20) and a housing ratio
investment significantly above the historical
trend.
29Long-run analysis (2)
- The IMF concludes that France was among the
countries that should experience the largest
decrease in the housing prices due to the the
 greatest exuberance in the house price. - It would be interesting to see how the authors
arguments can be corroborate by a statistical
analysis and why their depart from the IMF
findings.
30- Thanks for your attention