Title: The R
1The Rôle of Price Expectations in the U.K.
Housing Market
2Introduction
- Forward-looking expectations play a crucial
lead in the determination of house prices for
builders, buyers, sellers, etc. - The majority of housing studies include only the
expectations of the general price level, if they
deal with expectations at all. - It is suggested in the theoretical literature
that there is a strong link between housing
expectations and the state of the economy. A
factor in the latest recession. For example,
expectations of falling house prices can reduce
consumer spending. - The paper explains theoretically the formation of
expectations and applies that to RICS survey data
of house price expectations over the next three
months, or more, in conjunction with both the
Nationwide and Halifax actual house price
indices.
3The Data
- There are several sources of actual data on house
prices the Halifax, the Nationwide, the Land
Registry and the Financial Times indices. - The mortgage lenders series provide the longest
run of monthly, non-seasonal statistics, and
therefore, are adopted in this empirical
investigation. Also, the Land Registry series is
behind the times because it lags actual
transactions the lenders series by contrast,
lead transactions. - The Figure on the next slide shows the
fluctuations in the logarithmic growth rate of
Halifax prices over the next three months, that
is the logarithm at time (T4) minus the
logarithm at time (T1). The Nationwide index
would give similar results.
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5The Theoretical Model
- The formation of forward-looking expectations can
be modelled on the basis of bounded rationality
and the interdependence of agents, described as a
process of diffusion. - Those agents with the resources to form accurate
expectations cheaply are a small number of
chartered surveyors who possess the knowledge of
the market and are part of an Institution that
publishes the expectations in the form of either
up, same or down . - This group is small relative to the majority,
which means that the distribution of expectations
will be initially slow, followed by a sudden
increase as the majority of agents adapt to the
change in predictions. - This sequence implies a nonlinear process of
diffusion, which can be captured by the logistic
function, represented by a S-shaped curve, shown
in the next slide.
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7The Empirical Estimation of the Diffusion Model
- A logistic model of expectation diffusion is
estimated using the RICS data on future price
trends. Given that the sames have changed
considerably over the time period, it is
necessary to normalise the data. - The ups and downs can be normalised so they
sum to one (or hundred), by calculating adjusted
variables. Then, either one of normalised ups
or normalised downs can be used because they
give perfectly symmetric results. - A technical difficulty, however, is that the
normalised ups contain some zeros, and it was
not possible to calculate the logarithms for
them. To overcome this problem, the zeros were
adjusted to 0.005 and the ones reduced to 0.995
so that the logistic variable could be derived.
8More on Empirical Estimation
- The statistical analysis, which explains the
logistic diffusion variable derived from the RICS
survey using the adjusted ups, employed the
Hendry methodology of general-to-specific
analysis together with price data from the
Halifax database over the period of 1999 M10 to
2009 M9. This is followed with the substitute
data set, the Nationwide, over the same period. - The significant variables in the equations are
explained on the next slides. - Both empirical models are similar.
9Halifax Model explaining RICS
- The dependent variable is the change in the
log(au/(1-au)) from the RICS survey - Explained by the forward-looking growth in the
Halifax price index, logarithm T4 minus
logarithm T1 - The dependent variable lagged 1, 5, 9 and 15
months - The Halifax growth lagged 16, 21 and 22 months
- One dummy variable for September in 2004
- The dynamics here are quite complicated,
suggesting some form of error correction.
10Nationwide Model explaining RICS
- The dependent variable is the change in
log(au/(1-au)) from the RICS survey - Explained by the forward-looking growth in the
Nationwide price index, logarithm T4 minus
logarithm T1, lagged one month - The dependent variable lagged 5 and 12 months
- The Nationwide growth lagged 14 and 24 months
- Two dummy variables for September 2004 and
December 2008.
11Econometric Estimation of the Forecasting Models
- The forecasting of future growth in house prices
is causally quite different to the explanation of
expectations. Simple reversal of a regression
equation in these circumstances is not possible. - Given the earlier models, the dependent variable
investigated was the change in the logarithms of
the house price index data over the next three
months, explained by relevant previous price
changes and logistic survey variables over the
period of 2000 M 10 to 2009 M10. - The list of variables with the Halifax series is
followed by the alternative observations, the
Nationwide, on the next two slides. - When comparing the two models, the Nationwide one
seems slightly superior statistically, explaining
ninety-four per cent of the variation.
12Halifax Forecasting Model
- The dependent variable is the three months
forward-looking growth rate using the Halifax
price index - Explained by the RICS survey diffusion variable,
log(au/(1-au)) and the lagged values of it at 11,
13, 22, and 24 months - The forward-looking growth rate lagged 1, 3, 4,
6, 7, 9, 10, 12 and 13 months.
13Nationwide Forecasting Model
- The dependent variable is the three months
forward-looking growth rate using the Nationwide
price index - Explained by the RICS survey diffusion variable
log(au/(1-au)) lagged 10, 14, 20, 21, 22, 23 and
24 months - The dependent variable lagged 1, 3, 4, 6, 7, 9,
11, 12, 17, 22 and 24 months.
14Comparison with an Alternative Form
- The logistic forecasting model of the Nationwide
was compared with the Pesaran/Thomas (PT)
procedure for generating price expectations. The
PT procedure involves analysis using the
backward-looking survey adjusted ups with the
inclusion of lagged residuals to explain
backward-looking price growth. The coefficients
from that analysis are then used in conjunction
with forward-looking adjusted ups and residuals
to generate the expected forward-looking change
in house prices. - The root mean squared forecast error (RMSFE) was
used to compare the three months models. The
equation with the logistic function led to lower
RMSFE. Results of these tests for the Nationwide
model are shown in the paper. - Given the complexity of the dependent variable
that developed from Hendry methodology with
further restrictions imposed on the model
compared with the previous slide, it was decided
to experiment with a lag length beyond 3 months.
When the lag length was put to 12 months ahead,
the equation next was derived.
15The Nationwide Forecasting model Twelve Months
Ahead
- The dependent variable is the log change of
forward-looking growth rate using the Nationwide
price index over the next twelve months - Explained by the RICS survey diffusion variable
log(au/(1-au)) lagged 1, 2, 6, 12, 13, 15 and 23 - The dependent variable lagged 1, 6,10, 11, 12, 22
and 23 months - One dummy variable for December 2007
- The statistical model suggests that the Survey
data contains more than just three months of
information, and could well contain a yearly
sequence of events. The answering practices of
the surveyors require investigation.
16 Forecasts based on the Yearly Model of the
Nationwide Price Index
- The study updated the dataset to May 2010, when
the Nationwide index was 337.4603 - The previous equation was revised
- The analysis made a forecast for June, then
updated the data, and forecast for July, and
revised the data again. This process continued
until the forecast for December - The forecasts are as follows
- June - 334.2268,
- July 332.6814,
- August 326.6403,
- September 327.0887,
- October 309.9837,
- November 297.3425,
- December 292.5050.
- The model is forecasting a general decline in the
price index with the June value representing a
turning-point in the data set.
17The Policy Implications of The Work
- The work shows precisely how the RICS survey can
be used to forecast the Halifax and Nationwide
house price indices. - Expectations of future house prices are important
for buyers (will prices go up after purchase?),
sellers (could more be derived by selling
later?), builders (will the house started fetch a
profit on completion?) and should be important
for the Government and the Bank of England (for
example, what will the effect on consumer
spending be?). - Expectations influence mortgage lenders. If
expectations are for falling prices, they are
reluctant to lend and tend to ration credit
because of the greater probability of default. If
expectations are for rising prices, lenders tend
to make loans to a greater range of borrowers
because of the rising value of collateral.
18Governments Housing Policy
- It would be useful to supplement this study with
a co-integration VAR analysis incorporating the
RICS survey data, to investigate the housing
market fundamentals which affect house price
expectations most, in both the short and long
runs. - This would be a useful study because the
Government can only realistically affect market
expectations indirectly, through market
fundamentals. - The first target of policy historically has
tended to be housing finance interest rates and
mortgage lender regulation. - The second target historically has tended to be
housing supply, using local authorities and
planning approval.
19Conclusions/Summary
- The study has focused on the process of the
formation of expectations of house prices
underlying the RICS Survey - The empirical investigation suggests that there
is a diffusion process, captured by the logistic
model. This is in line with models of bounded
rationality, where decision-making is uncertain,
self-fulfilling, complex and costly - The majority of agents in the market follow the
few, the alphas of the pack, namely the Chartered
Surveyors.