Presentation - Norges Bank
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Transcript Presentation - Norges Bank
Improving early warning indicators for
banking crises – satisfying policy
requirements
Mathias Drehmann and Mikael Juselius
Bank for International Settlements
“Understanding Macroprudential Regulation”
Norges Bank, Oslo, 29–30 November 2012
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CGFS report No 48
Operationalizing the selection and
application of macroprudential
instruments
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Operationalising macroprudential policies
Report focusses on 3 high-level criteria that are key in
determining instrument selection and application in practice
The ability to determine the appropriate timing for the
activation or deactivation of the instrument
The effectiveness of the MPI in achieving the stated objective
The efficiency of the instrument in terms of a cost-benefit
assessment
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Report ends with 9 questions and answers
1.
To what extent are vulnerabilities building up or crystallising?
2.
How (un)certain is the risk assessment?
3.
Is there a robust link between changes in the instrument and the
stated policy objective?
4.
How are expectations affected?
5.
What is the scope for leakages and arbitrage?
6.
How quickly and easily can an instrument be implemented?
7.
What are the costs of applying a macroprudential instrument?
8.
How uncertain are the effects of the policy instrument?
9.
What is the optimal mix of tools to address a given vulnerability?
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Report analysis three groups of macroprudential
instruments
Capital-based tools (countercyclical capital buffers, sectoral
capital requirements and dynamic provisions)
Liquidity-based tools (countercyclical liquidity requirements)
Asset-side tools (loan-to- value (LTV) and debt-to-income (DTI)
ratio caps)
For all tools report proposes ‘transmission maps’
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Transmission map for capital based tools
Voluntary
buffers
Loan market
Leakages
to nonbanks
↑ lending
spreads
dividend and
bonuses
Reprice
loans
credit
demand
Undertake SEOs1
Arbitrage
away
credit supply
assets,
especially with
high RWA
Expectation channel
↑ Loss
Absorbency
Tighter risk
management
Increase resilience
Asset
prices
Impact on the credit cycle
Increase capital requirements or
provisions
Options to address
shortfall
Improving early warning indicators for
banking crises – satisfying policy
requirements
7
Introduction
CGFS (2012): Policymakers need to be able to determine the
appropriate timing for the activation or deactivation of the
instrument
In this paper we want to find reliable early warning indicators
(EWIs) for systemic banking crises
What policy requirements do EWIs need to satisfy?
Need to be evaluated with preference free methodology
Need to have right timing
Need to be stable
Need to be robust
Need to be understood by policymakers
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Implementing the framework
We assess a broad range of indicators
We find
Credit-to-GDP gap best indicator for predicting crises 2-5 years
in advance
Debt service ratios highly successful indicator for predicting
crises 1-2 years in advance
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How to evaluate the goodness of an EWI?
To fully evaluate quality of a signal would need to know preferences
of policymakers, which are unknown (eg CGFS (2012))
What are costs of acting on wrong signals (false positives)?
What are the benefits of acting on correct signals (true
positives)?
→ Need to evaluate signalling quality independent of preferences
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The ROC curve
Policymakers receive noisy signal S
S higher → higher risk of a crisis
At which threshold you policymakers act?
1
W1
Fully informative signal
Uninformative signal
Informative signal
W2
1
1
W2
True
positive
rate
True
positive
rate
True
positive
rate
W1
False positive rate
1
False positive rate
1
False positive rate
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1
11
Area under ROC curve as measure of signalling quality
Area under the ROC curve (AUROC) provides summary measure
of the classification ability (eg Jorda and Taylor, 2011):
AUROC
1
ROC ( FP )dFP
0
AUROC=0.5 → uninformative indicator
AUROC=1 → fully informative indicator
AUROC ideal measure if preferences are not known
Benefits
Can be estimated non-paramterically
Has convenient statistical properties
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Timing of ideal EWIs
Ideal EWI needs to signal crisis early enough
Likely to be 1-2 year lead-lag relationship (e.g. countercyclical
capital buffers)
Policymakers tend to observe trends before reacting (e.g.
Bernanke, 2004)
Ideal EWI signal crises not too early
Introducing buffers too early may undermine effectiveness
(e.g. Caruana, 2010)
We look at individual quarters within a 5 year horizon
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EWIs need to be stable and robust
Policymakers adjust policy stance gradually
Optimal for MP (Bernanke, 2004, Orphanides, 2003)
Indictor should issue consistent signals
Consistency of signal tied to persistency of underlying series
(eg Park and Phillips (2000))
High degree of persistency problematic for statistical inference
Non-parametric approach
EWIs need to be robust to different samples and specifications
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Interpretability of EWI
Evidence that practitioners value sensibility of forecasts more
than accuracy (Huss, 1987) adjust forecasts if the lack justifiable
explanations (Onka-Atay et al (2009)
Purely statistical approaches are not suitable for policy
purposes and communication
Our indicators reflect
excessive leverage and asset price booms (Kindleberger, 2000,
and Minsky, 1982)
non-core deposits (Hahm et al, 2012)
the business cycle
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Analysing potential EWIs
We construct and test a range of potential early warning
indicators building on Drehmann et al (2011)
We select indicator variables from...
Credit measures: Credit-to-GDP gap and real credit growth
Asset prices: Real property and equity price gaps and real
property and equity price growth
None-core bank liabilities (Hahm, Shin, and Shin (2012)):
GDP growth
History of financial crises
...and add one new measure:
Debt service ratio (DSR) (Drehmann and Juselius (2012)):
interest payments and repayments on debt divided by income
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Analysing potential EWIs (II)
We analyse quarterly time-series data from 27 countries.
The sample starts in 1980 for most countries and series, and at
the earliest available date for the rest
Use balanced sample
We follow the dating of systemic banking crises in Laeven and
Valencia (2012)
We ignore crises which are driven by cross-boarder exposures
We adjust dating for some crisis after discussions with CBs
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Persistency
Several of the variables display dynamics which are hard to
distinguish from I(2) process
Indicators which have performed well in the past are more
persistent
→ Benefits of a non-parametric approach
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Behaviour around systemic crises
Property pr. gap
Equity pr. gap
GDP growth
-8
-4
0
4
8
12
-20 -16 -12
-4
0
4
8
10
0
-5
-20 -16 -12
-4
0
4
8
12
-20 -16 -12
Prop. price gr.
-8
-4
0
4
8
12
-20 -16 -12
Equity price gr.
-4
0
4
8
12
0
4
8
12
-20 -16 -12
-8
-4
0
4
8
12
-20 -16 -12
-8
-4
0
4
8
12
0
-2 0
-2 0
-1 0
-5 0
.5
0
0
0
0
1
20
10
20
50
1 .5
40
20
-8
his tory
1 00
40
Credit growth
-8
-1 0
-5 0
12
60
Non-core deposit ratio
-8
2
-20 -16 -12
-4 0
-5
-2 0
0
-2 0
0
0
0
5
20
50
5
20
10
40
40
1 00
Credit-to-GDP gap
15
DSR
-20 -16 -12
-8
-4
0
4
8
12
-20 -16 -12
-8
-4
0
4
8
12
-20 -16 -12
-8
-4
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ROC curves for 2 year forecast horizon
.6
.8
1
.6
.4
FP
.8
1
1
.8
1
.6
RO C
.4
.2
.4
0
.8
0
1
.6
.4
FP
.8
1
.6
.8
1
.6
.8
1
1
.8
1
RO C
.6
RO C
.4
.2
.2
.4
History
0
0
.2
FP
.8
1
.6
RO C
.4
.2
.6
.4
Equity price gr.
.2
0
.2
FP
0
0
.8
0
1
.8
1
.6
RO C
.4
FP
.8
Prop. price gr.
.2
.6
.4
.6
.4
FP
.8
1
.8
.6
RO C
.4
.2
0
.2
.2
Credit growth
Non-core deposi ts ratio
0
0
0
1
FP
.6
.4
.4
.2
.2
0
1
FP
0
.8
.2
.4
.2
0
0
.6
.4
.6
RO C
.6
RO C
.6
RO C
.4
.2
.2
.8
1
.8
1
.8
1
.8
.6
RO C
.4
.2
0
0
GDP growth
Equity pr. gap
Property pr. gap
Credit-to-GDP gap
DSR
0
.2
.6
.4
FP
.8
1
0
.2
.4
FP
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20
1
1
.8
.7
.5
.6
A URO C
.5
.6
A URO C
.7
-15
-5
.4
.3
Property pr. gap
0
-20
-15
Equity pr. gap
-5
0
-20
-15
-10
GDP growth
-5
0
-20
-15
.9
-10
-5
0
-5
0
Horizon
1
1
Horizon
.6
A URO C
.5
A URO C
.6
.7
.7
-15
-10
Horizon
-5
0
-20
-15
-10
Horizon
-5
0
.4
.3
.2
Prop. price gr.
-20
-15
-10
Horizon
Equity price gr.
-5
0
-20
-15
-10
Horizon
His tory
.2
.2
Credit growth
.2
.2
Non-core deposits ratio
-20
.3
.4
.3
.4
.3
.3
.4
.4
.5
.5
.6
A URO C
.7
.6
.5
.5
.6
A URO C
.7
.7
.8
.8
.9
.8
.9
.8
-10
Horizon
1
Horizon
1
Horizon
-10
1
-20
.2
Credit-to-GDP gap
0
.9
-5
.9
-10
.8
-15
.2
.2
DSR
-20
.2
.2
.3
.3
.3
.3
.4
.4
.4
.4
.5
.6
A URO C
.7
.6
.5
.5
.6
A URO C
.7
.7
.8
.8
.9
.9
1
.9
1
.9
.8
.8
.9
1
ROC curves over time
-5
0
-20
-15
-10
Horizon
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Credit to GDP gap and
property price gap
DSR and property price
gap
-20
-15
Horizon
-5
0
1
Credit/GDP gap
-20
-15
DSR
Credit\GDP gap and DSR
-10
Horizon
-5
DSR
.2
Credit\GDP gap and prop. gap
-10
.2
Property gap
.3
.4
.5
.6
A UR OC
.7
.8
.9
1
.9
.8
.7
.6
.5
.4
.3
.4
.5
.6
A UR OC
.7
.8
.9
1
Credit to GDP gap and
DSR
.3
Credit/GDP gap
.2
A UR OC
Combining variables
0
-20
-15
Property gap
DSR and prop. gap
-10
-5
0
Horizon
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Robustness checks
Robust across samples
Robust to different crisis dating
Robust to balanced versus unbalanced samples
Robust if partial ROC curves are used
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Conclusion
We argue that EWIs need satisfy six policy requirements:
Need to be evaluated with preferences free methodology
Need to have right timing
Need to be stable
Need to be robust
Need to be understood by policymakers
Appliying this approch to data from 27 countries we find that:
The DSR and the credit-to-GDP gap dominate other EWIs
The DRS dominates at shorter horizons and the credit-to-GDP
gap dominates at longer ones
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