pavel v. shevchenko quantitative risk management csiro...

38
Quantitative modelling of financial risks Pavel V. Shevchenko Quantitative Risk Management CSIRO Mathematical and Information Sciences Australia-Japan Workshop on Data Science Keio University, 24-27 March 2009

Upload: others

Post on 29-Sep-2020

6 views

Category:

Documents


0 download

TRANSCRIPT

Page 1: Pavel V. Shevchenko Quantitative Risk Management CSIRO ...lab.datascience.jp/AJF/presentations/Shevchenko.pdf · CSIRO Mathematical & Information Sciences Track Records in Financial

Quantitative modelling of financial risks

Pavel V. ShevchenkoQuantitative Risk Management

CSIRO Mathematical and Information Sciences

Australia-Japan Workshop on Data ScienceKeio University, 24-27 March 2009

Page 2: Pavel V. Shevchenko Quantitative Risk Management CSIRO ...lab.datascience.jp/AJF/presentations/Shevchenko.pdf · CSIRO Mathematical & Information Sciences Track Records in Financial

CSIRO Mathematical & Information Sciences www.cmis.csiro.au

Financial Risk in QRM

CMIS Quantitative Risk Management (QRM) group:• 20 researchers www.cmis.csiro.au/QRM• Financial risk, infrastructure, security, air-transport• Activities/modes of engagement: research, consulting, model

development/validation, software developmentFinancial risk team in QRM: 6 researchersIndustry: banks, insurance/electricity companies, hedge fundsBeneficiaries of our work in risk management:• Financial institutions and their shareholders (risk reduction)• Stability of banking/insurance systems• Science and CMIS (reputation, external earnings, IP)Our mission – To conduct research in financial risk quantification,

measurement and calculation; To develop innovative quantitativemethods and tools in financial engineering

Page 3: Pavel V. Shevchenko Quantitative Risk Management CSIRO ...lab.datascience.jp/AJF/presentations/Shevchenko.pdf · CSIRO Mathematical & Information Sciences Track Records in Financial

CSIRO Mathematical & Information Sciences www.cmis.csiro.au

Track Records in Financial Risk since 1999

External Projects• Derivative pricing: option pricing software Reditus/Fenics since 1999• Operational Risk: risk engines for 2 major banks in Australia, validation,

model development and software development projects• Market Risk: validation and model development projects• Credit Risk: validation and model development projects• Insurance-Underwriting risk: consulting projects• Electricity: consulting projects• Commodities/interest rates: consulting projectsStrategic research projects: operational/credit/market risks, option pricing,

commodity/interest rate modelling, portfolio allocationCollaborators: Swiss Federal Institute of Technology (ETH Zurich), Vienna Uni

of Technology, Monash Uni, Cambridge Uni, UNSW, UTS, Macquarie Uni, Statistical Research Associates NZ.

Page 4: Pavel V. Shevchenko Quantitative Risk Management CSIRO ...lab.datascience.jp/AJF/presentations/Shevchenko.pdf · CSIRO Mathematical & Information Sciences Track Records in Financial

CSIRO Mathematical & Information Sciences www.cmis.csiro.au

Links•Extreme Value models•Expert Elicitation•Combining expert&data•Bayesian methods•Dependence modelling•Numerical methods (PDE, MCMC, MC)•Time series analysis•State-space models•High performance computing•Optimisation

Other risk areas•Air transport•Ecology•Environment•Infrastructure •Security•Weather/Climate•Health

Financial Risk• Market Risk • Credit Risk • Operational Risk• Underwriting risk • Derivative pricing• Interest Rates• Trading strategies• Portfolio Management• Commodity/Energy• Carbon Trading• Liquidity risk

Financial risk and other risk areas

Page 5: Pavel V. Shevchenko Quantitative Risk Management CSIRO ...lab.datascience.jp/AJF/presentations/Shevchenko.pdf · CSIRO Mathematical & Information Sciences Track Records in Financial

CSIRO Mathematical & Information Sciences www.cmis.csiro.au

Regulatory Requirements for banking industry

•Regulatory standards in banking industry:Basel Committee for banking supervision 1974Basel I, 1988: Credit Risk, Basel I Amendment 1996: Market Risk (VaR) Basel II 2001- ongoing: Credit Risk, Operational Risk

•Insurance regulation: International Association of Insurance SupervisorsJoint Forum on Financial Conglomerates 1996Solvency II (similar to Basel II for banks)

Page 6: Pavel V. Shevchenko Quantitative Risk Management CSIRO ...lab.datascience.jp/AJF/presentations/Shevchenko.pdf · CSIRO Mathematical & Information Sciences Track Records in Financial

CSIRO Mathematical & Information Sciences www.cmis.csiro.au

Basel II• Basel II requires that banks hold adequate capital to protect

against Market risk, Credit risk and Operational Risk losses. Three-pillar framework:

Pillar 1: minimal capital requirements (risk measurement)Pillar 2: supervisory review of capital adequacyPillar 3: public disclosure

Advanced Measurement Approaches allow internal models for calculations of capital as a large quantile of loss distribution.Operational Risk is new risk category

• In Australia, the national regulator APRA is now applying the Basel II requirements.

• Solvency 2 for insurance industry

Page 7: Pavel V. Shevchenko Quantitative Risk Management CSIRO ...lab.datascience.jp/AJF/presentations/Shevchenko.pdf · CSIRO Mathematical & Information Sciences Track Records in Financial

CSIRO Mathematical & Information Sciences www.cmis.csiro.au

Financial Risks – quantifying uncertainties

Risks are modelled by random variables mapping unforeseen future states of the world into values representing profits and losses.

Market Risk: modelling of losses incurred on a trading book due market movements (interest rates, exchange rates, etc)

Credit risk: modelling of losses from credit downgrades and defaults (e.g. loan defaults)

Operational Risk: modelling of losses due to failed internal processes, people or external events (e.g. human errors, IT failures, natural disasters, etc)

Quantifying the uncertainties: process uncertainty, parameter uncertainty, numerical error, model error

Page 8: Pavel V. Shevchenko Quantitative Risk Management CSIRO ...lab.datascience.jp/AJF/presentations/Shevchenko.pdf · CSIRO Mathematical & Information Sciences Track Records in Financial

CSIRO Mathematical & Information Sciences www.cmis.csiro.au

Regulatory Requirements – Risk MeasuresValue at Risk (VaR)

loss probability density

0

0.01

0.02

0.03

0.04

0$ loss

Expected Loss

Unexpected Loss

10daysover 0.99 :kMarket Ris1year over :kCredit Ris year1over 999.0 : RisklOperationa

}1]Pr[:inf{ :measureRisk

loss expectedloss Unexpected

=••=•

−≤>=•

−=•

qq

qxLossxVaR

VaR

q

q

Page 9: Pavel V. Shevchenko Quantitative Risk Management CSIRO ...lab.datascience.jp/AJF/presentations/Shevchenko.pdf · CSIRO Mathematical & Information Sciences Track Records in Financial

CSIRO Mathematical & Information Sciences www.cmis.csiro.au

Market, Credit and Operational Risks

jXXN

jZ

XZZL

pIIX

IXLM

XSSSXZX

SSQ

K

jjN

jj

j

jN

i

jij

jj

iii

M

iii

tttttttttt

K

k

Mttttkt

risk for severities andfrequency annual theare ,..., and

risk todue loss annual theis

; :risk lOperationa

defaultof prob. is]1Pr[ ;0or1 default;givenloss is

:obligors of portfolio :riskCredit

)(,/)( ;

etc FX,s,commoditie stocks, ),...,();(

contracts financial of portfolio :riskMarket

)()(1

1

)(56

1

1

21

20110

2110

1

)()1(

∑=∑=•

===

∑ ×=•

+−+=−=+=

∑ ==Π

==

=

−−−−

=

βσμαασσμ

SS

Page 10: Pavel V. Shevchenko Quantitative Risk Management CSIRO ...lab.datascience.jp/AJF/presentations/Shevchenko.pdf · CSIRO Mathematical & Information Sciences Track Records in Financial

CSIRO Mathematical & Information Sciences www.cmis.csiro.au

Basel II, Operational Risk

•Basel II defined Operational Risk as: the risk of loss resulting from inadequate or failed internal processes, people and systemsor from external events. This definition includes legal risk but excludes strategic and reputational risk.

•Losses can be extreme, e.g.1995: Barings Bank (loss GBP1.3billion)1996: Sumitomo Corporation (loss US$2.6billion)2001: September 112001: Enron, USD 2.2b (largest US bankruptcy so far)2002: Allied Irish, £450m2004: National Australia bank (A$360m)2008: Société Générale (Euro 4.9billion)

Page 11: Pavel V. Shevchenko Quantitative Risk Management CSIRO ...lab.datascience.jp/AJF/presentations/Shevchenko.pdf · CSIRO Mathematical & Information Sciences Track Records in Financial

CSIRO Mathematical & Information Sciences www.cmis.csiro.au

Operational Risk Basel II Business Lines/Event Types

Basel II Business Lines (BL)• BL(1) - Corporate finance• BL(2) - Trading & Sales• BL(3) - Retail banking• BL(4) - Commercial banking• BL(5) - Payment & Settlement• BL(6) - Agency Services• BL(7) - Asset management• BL(8) - Retail brokerage

Basel II Event Type (ET)•ET(1) - Internal fraud:•ET(2) - External fraud: •ET(3) - Employment practices and

workplace safety: •ET(4) - Clients, products and

business practices•ET(5) - Damage to physical assets:•ET(6) - Business disruption and

system failures: •ET(7) - Execution, delivery and

process management:

Page 12: Pavel V. Shevchenko Quantitative Risk Management CSIRO ...lab.datascience.jp/AJF/presentations/Shevchenko.pdf · CSIRO Mathematical & Information Sciences Track Records in Financial

CSIRO Mathematical & Information Sciences www.cmis.csiro.au

Loss Data Collection Exercise 2007 Japan - Annualized data: Number of events(100%=947.7) / Total Loss Amount (100%=JPY 22,650mln)

100% (no.events)100% (loss)

38.6%54.6%

10.9%3.9%

1.9%4.5%

8.8%24.8%

1.5%1.0%

36.5%8.3%

1.8%2.9%

Total

0.4%0.2%

0.02%0.00%

0.09%0.00%

0.13%0.00%

0.00%0.00%

0.02%0.00%

0.11%0.00%

0.09%0.18%

Other

3.5%2.0%

1.06%0.13%

0.18%0.04%

0.00%0.00%

1.40%0.53%

0.01%0.00%

0.00%0.00%

0.84%1.32%

BL(8)

2.1%1.5%

1.50%1.02%

0.05%0.00%

0.00%0.00%

0.48%0.49%

0.1%0.04%

0.00%0.00%

0.00%0.00%

BL(7)

5.3%3.8%

3.14%3.00%

1.19%0.22%

0.01%0.00%

0.92%0.62%

0.01%0.00%

0.00%0.00%

0.00%0.00%

BL(6)

0.6%0.1%

0.23%0.00%

0.38%0.04%

0.00%0.00%

0.00%0.00%

0.00%0.00%

0.00%0.00%

0.00%0.00%

BL(5)

25.7%45.4%

15.05%16.87%

5.87%3.22%

0.69%4.19%

2.02%18.32%

1.16%0.71%

0.64%1.99%

0.29%0.13%

BL(4)

57.2%21.5%

13.21%8.43%

2.83%0.26%

1.11%0.26%

3.62%4.77%

0.14%0.18%

35.73%6.36%

0.54%1.24%

BL(3)

4.7%25.2%

4.12%25.03%

0.26%0.00%

0.00%0.00%

0.22%0.09%

0.04%0.04%

0.00%0.00%

0.01%0.00%

BL(2)

0.5%0.3%

0.28%0.18%

0.07%0.04%

0.00%0.00%

0.11%0.09%

0.01%0.00%

0.01%0.00%

0.00%0.00%

BL(1)

TotalET(7)ET(6)ET(5)ET(4)ET(3)ET(2)ET(1)

Ban

k of

Jap

an, e

t al (

2007

)

Page 13: Pavel V. Shevchenko Quantitative Risk Management CSIRO ...lab.datascience.jp/AJF/presentations/Shevchenko.pdf · CSIRO Mathematical & Information Sciences Track Records in Financial

CSIRO Mathematical & Information Sciences www.cmis.csiro.au

Loss Data Collection Exercise 2004 USA - Annualized data: Number of events(100%=18371) / Total Loss Amount (100%=USD 8,643mln)

Fede

ral R

eser

ve S

yste

m, e

t al (

2005

)

100.0%, 100.0% (US$)

3.2%0.6%

0.8%0.1%

35.3%9.6%

0.7%0.8%

0.7%1.4%

9.2%79.8%

7.6%1.7%

39.0%5.1%

3.40%0.9%

Total

8.0%70.8%

0.08%0.01%

0.07%0.05%

3.45%0.98%

0.02%0.44%

0.12%1.28%

0.40%67.34%

1.75%0.34%

1.66%0.3%

0.42%0.1%

Other

7.3%1.6%

0.20%0.07%

2.20%0.25%

0.01%0.00%

3.30%0.94%

1.38%0.33%

0.10%0.02%

0.06%0.03%

BL(8)

2.4%2.5%

0.09%0.01%

1.82%0.38%

0.04%0.01%

0.00%0.00%

0.13%2.10%

0.10%0.02%

0.26%0.02%

0.00%0.00%

BL(7)

5.1%1.1%

4.52%0.99%

0.14%0.02%

0.01%0.01%

0.31%0.06%

0.04%0.02%

0.03%0.01%

0.01%0.02%

BL(6)

4.5%0.6%

0.23%0.05%

0.01%0.00%

2.99%0.28%

0.05%0.02%

0.01%0.00%

0.04%0.01%

0.18%0.02%

0.44%0.13%

0.52%0.08%

BL(5)

5.1%1.8%

0.44%0.04%

0.02%0.00%

1.38%0.28%

0.03%0.00%

0.01%0.00%

0.36%0.78%

0.17%0.03%

2.64%0.70%

0.05%0.01%

BL(4)

60.1%12.3%

2.10%0.26%

0.69%0.06%

12.28%3.66%

0.21%0.21%

0.56%0.1%

4.41%4.01%

3.76%0.87%

33.85%2.75%

2.29%0.42%

BL(3)

7.3%8.6%

0.05%0.15%

6.55%2.76%

0.24%0.06%

0.03%0.00%

0.19%4.29%

0.17%0.05%

0.01%1.17%

0.02%0.10%

BL(2)

0.3%0.5%

0.01%0.00%

0.03%0.01%

0.12%0.05%

0.00%0.00%

0.08%0.30%

0.06%0.03%

0.01%0.00%

0.01%0.14%

BL(1)

TotalFraudOtherET(7)ET(6)ET(5)ET(4)ET(3)ET(2)ET(1)

Page 14: Pavel V. Shevchenko Quantitative Risk Management CSIRO ...lab.datascience.jp/AJF/presentations/Shevchenko.pdf · CSIRO Mathematical & Information Sciences Track Records in Financial

CSIRO Mathematical & Information Sciences www.cmis.csiro.au

Internal

Loss Data

External

Loss Data

Scenario analysis

Risk Frequency and Severity distributions

Annual loss distribution (per risk and over all risks)

Annual Capital Charge (Capital Allocation, sensitivity, what if scenarios)

Business environment and internal control factors

Insurance Dependence between risks

Operational Risk - Loss Distribution Approach

Monte Carlo simulations

Page 15: Pavel V. Shevchenko Quantitative Risk Management CSIRO ...lab.datascience.jp/AJF/presentations/Shevchenko.pdf · CSIRO Mathematical & Information Sciences Track Records in Financial

CSIRO Mathematical & Information Sciences www.cmis.csiro.au

Operational Risk: Combining internal data, industry data and expert opinions

• BIS (2006), p.152: “Any operational risk measurement system must have certain key features to meet the supervisory soundnessstandard set out in this section. These elements must include the use of internal data, relevant external data, scenario analysis and factors reflecting the business environment and internal controlsystems.”

• An interview with four industry’s top risk executives: Davis, E. (1 September 2006). Theory vs Reality, OpRisk and Compliance: “[A] big challenge for us is how to mix the internal data with external data; this is something that is still a big problem because I don’t think anybody has a solution for that at the moment.” Or: “What can we do when we don’t have enough data [. . .] How do I use a small amount of data when I can have external data with scenario generation? [. . .] I think it is one of the big challenges for operational risk managers at the moment”.

Page 16: Pavel V. Shevchenko Quantitative Risk Management CSIRO ...lab.datascience.jp/AJF/presentations/Shevchenko.pdf · CSIRO Mathematical & Information Sciences Track Records in Financial

CSIRO Mathematical & Information Sciences www.cmis.csiro.au

Ad-hoc procedures for combining internal data, industry data and expert opinions (SA)

)]ˆvar(:min[argˆ;1...,ˆ...ˆˆ.estimators moreor threecombine toextendedeasily be Can

ˆ,ˆ:)ˆvar( minimize to weightsChoose

)1()ˆvar(;1,ˆˆˆ :estimator unbiased Combined

.2,1,]ˆvar[;]ˆ[ i.e. ,parameter for ˆ and ˆ estimatest independen unbiased woconsider t : varianceMinimum

)()1()()(:onsdistributi Mixingseverity estimate data to external&internal

of sample combined andfrequency estimate data to Internal

111

22

21

21

222

21

22

1

22

21

21

21212211

221

21int21

totKKKtot

tot

tottot

mmm

extSA

wwwwww

ww

wwwwww

mE

xFwwxFwxFw

θθθθ

σσσ

σσσθ

σσθθθθ

σθθθθθθ

==++++=

+=

+=

−+==++=

===

•−−++•

Page 17: Pavel V. Shevchenko Quantitative Risk Management CSIRO ...lab.datascience.jp/AJF/presentations/Shevchenko.pdf · CSIRO Mathematical & Information Sciences Track Records in Financial

CSIRO Mathematical & Information Sciences www.cmis.csiro.au

Combining three data sources: internal&externaldata and expert opinion via Bayesian inference

ion)approximat Gaussian methods, MCMCpriors, (conjugatedensity posterior -),|(

opinionsexpert of likelihood- )|(nsobservatio internal of likelihood-)|(

dataindustry by estimated is ondistributiprior -)(

)()|()|(),|(

),...,,( ),...,,( ),...,,(sParameter opinions Expert data Internal

2

1

21

212121

υXθθυθX

θ

θθυθXυXθ

θυX

π

π

ππ

θθθυυυ

hh

hh

XXX KMn

===

Joint work with ETH Zurich: H. Bühlmann, M.Wüthrich, D.Lambrigger

Page 18: Pavel V. Shevchenko Quantitative Risk Management CSIRO ...lab.datascience.jp/AJF/presentations/Shevchenko.pdf · CSIRO Mathematical & Information Sciences Track Records in Financial

CSIRO Mathematical & Information Sciences www.cmis.csiro.au

Combining internal & external data with expertExample: Poisson-Gamma-Gamma

5.0)|(,7.0ˆ:Expert15.0,41.33/2]75.025.0Pr[,5.0][:data External

(0.6) from 0) 2, 1, 1, 2, 0, 1, 1, 1, 0, 1, 0, 0, 0, (0, :counts Annual

==≈≈⇒=≤≤=

=

λυυβαλλ

VcoE

PoissonN

year

Arr

ival

rate

Page 19: Pavel V. Shevchenko Quantitative Risk Management CSIRO ...lab.datascience.jp/AJF/presentations/Shevchenko.pdf · CSIRO Mathematical & Information Sciences Track Records in Financial

CSIRO Mathematical & Information Sciences www.cmis.csiro.au

Modelling dependence

•Basel Committee statement“Risk measures for different operational risk estimates must be added for purposes of calculating the regulatory minimum capitalrequirement. However, the bank may be permitted to use internally determined correlations in operational risk losses across individual operational risk estimates, provided it can demonstrate to the satisfaction of the national supervisor that its systems for determining correlations are sound, implemented with integrity, and take into account the uncertainty surrounding any such correlation estimates (particularly in periods of stress). The bank must validate its correlation assumptions using appropriate quantitative and qualitative techniques.” BIS (2006), p.152.

•Remark: Adding capitals implies perfect positive dependence between risks which is too conservative

Page 20: Pavel V. Shevchenko Quantitative Risk Management CSIRO ...lab.datascience.jp/AJF/presentations/Shevchenko.pdf · CSIRO Mathematical & Information Sciences Track Records in Financial

CSIRO Mathematical & Information Sciences www.cmis.csiro.au

Dependence between risks

Sampler) (Slice via MCMCncalibratio :)parameters c(stochasti profilesrisk thebetween Dependence•

, and losses annual thebetween Dependence• timesame at the occured severities thebetween Dependence•cellsrisk many affecting events common via theDependence•

, and sfrequencie thebetween Dependence•)](|[)(:(ES) shorfall Expected•

failmay ationdiversificformally and measure coherent a not is },)(,min{)()( :VaR•

)C()C()C( :capitala in ationdiversific Possible•

...:

11

1

)(2

1

)2(1

1

)1(

1

jiZZ

jiNNZVaRZZEZES

zFzFZVaR

ZZZ

XXXZZlossannualtotal

ji

ji

ZZ

K

KN

i

Ki

N

ii

N

ii

K

kk

≠>=

≥==

+…+≤

+++==

====∑∑∑∑

αα

α αα

Page 21: Pavel V. Shevchenko Quantitative Risk Management CSIRO ...lab.datascience.jp/AJF/presentations/Shevchenko.pdf · CSIRO Mathematical & Information Sciences Track Records in Financial

CSIRO Mathematical & Information Sciences www.cmis.csiro.au

Example: dependence between frequency profiles;dependence between severity profiles

.,between copula)( ;,between copula)(

.parameter copulaGaussian vs),(n correlatiorank sSpearman'(2)(1)(2)(1)

)2()1(S

μμλλ

ρρ

−∗−o

ZZ

copula via,,between dependence

)1,1(~ and )1.0,2(~),10,4(~

),(~)(),(~

)( and )(

)()()(

)()()(

)()()()()(

)(

1

)()()(

1

)()(

jt

jt

jt

jt

jt

jt

jt

jt

is

jt

jt

jtN

s

js

jt

itN

s

is

it

GammaNGamma

LNtXPoissonN

tXZtXZ

σμλ

σμλ

σμλ

∑=∑===

Page 22: Pavel V. Shevchenko Quantitative Risk Management CSIRO ...lab.datascience.jp/AJF/presentations/Shevchenko.pdf · CSIRO Mathematical & Information Sciences Track Records in Financial

CSIRO Mathematical & Information Sciences www.cmis.csiro.au

Parameter Risk (uncertainty of parameters)

densityposterior the),()|()|(]ˆˆ[

MLEestimator,point a is ˆ);ˆ|(ofquantile999.0ˆ)|(ofquantile999.0ˆ

ondistributipredictive full)|()|()|(,...,1 nsobservatiopast ),(

; year in loss)(

999.0999.0

1999.0

1999.0

11

1

θθYYθ

θθ

Y

θYθθYNXY

ππ

ϕ

πϕ

hQQEbias

ZgQ

ZQ

dZgZMt

ttXZ

BM

MB

MM

tN

iit

∝•−=

−•

−•

−∫ ×=•=−=•

−∑=

+

+

++

=

Page 23: Pavel V. Shevchenko Quantitative Risk Management CSIRO ...lab.datascience.jp/AJF/presentations/Shevchenko.pdf · CSIRO Mathematical & Information Sciences Track Records in Financial

CSIRO Mathematical & Information Sciences www.cmis.csiro.au

Parameter Risk (uncertainty of parameters)

0%

50%

100%

150%

200%

250%

5 10 15 20 25 30 35 40Year

% b

ias

LognormalPareto

Relative bias in the 0.999 quantile estimator induced by the parameter uncertainty vs number of observation years. (Lognormal) - losses were simulated from Poisson(10) and LN(1,2). (Pareto) – losses were simulated from Poisson(10) and Pareto(2) with L=1.

Page 24: Pavel V. Shevchenko Quantitative Risk Management CSIRO ...lab.datascience.jp/AJF/presentations/Shevchenko.pdf · CSIRO Mathematical & Information Sciences Track Records in Financial

CSIRO Mathematical & Information Sciences www.cmis.csiro.au

Modelling commodities/interest rates: state-space models

• Measurement Equation:• Transition Equation:

ttTtttTTt

ttttt

ttt

ttt

Ttttt

tTCtTBtTAThFSEF

dtdWdWEdWdtd

dWdtd

thSFS

χξξχ

ρσδκλχ

σωξλμξ

χξ

χξ

χ

ξ

)()()()(ln],|[

][;][

][

)(lnprices futures rates, long/short,price;spot

,,

)2()1()2(21

)1(1

,

−+−+−+=⇒=

=+−−=

+−−=

++=

−−−

• Commodity spot models: e.g. 2-factor long-short

eXBAF ttrrrr

+×+= ˆ

εrrrr

+×+=+ tt XTMX ˆ1

• Non-Gaussian models/fitting option prices – calibration requires non-linear Kalman filter, particle filter/SMC

Page 25: Pavel V. Shevchenko Quantitative Risk Management CSIRO ...lab.datascience.jp/AJF/presentations/Shevchenko.pdf · CSIRO Mathematical & Information Sciences Track Records in Financial

CSIRO Mathematical & Information Sciences www.cmis.csiro.au

Seasonal and non-seasonal commodities

Crude Oil Future Prices vs maturity month

$60

$62

$64

$66

$68

$70

1 3 5 7 9 11

fitted on 24/02/2006obs on 24/02/2006

Crude Oil standard deviation vs maturity month

20%

22%

24%

26%

28%

30%

32%

1 3 5 7 9 11

fittedobserved

Soy Beans Future Prices vs maturity

$500

$520

$540

$560

$580

$600

1 2 3 4 5 6 7

fitted on 19/10/2004observed on 19/10/2004

standard deviation vs maturity

18%19%20%21%22%23%24%25%26%27%

1 2 3 4 5 6 7

observedfitted

Page 26: Pavel V. Shevchenko Quantitative Risk Management CSIRO ...lab.datascience.jp/AJF/presentations/Shevchenko.pdf · CSIRO Mathematical & Information Sciences Track Records in Financial

CSIRO Mathematical & Information Sciences www.cmis.csiro.au

Pricing Exotic Options: Stochastic Volatility, Implied Volatility Smile

0

200

400

600

800

1000

1200

1400

1600

1800

24/07/1998 6/12/1999 19/04/2001 1/09/20020

0.1

0.2

0.3

0.4

0.5

0.6S&P500Historic vol

800

830

860

890

920

950

980 0.14

0.26

0.39

0.51

0.15

0.2

0.25

0.3

0.35

0.4

implied volatility

strike

maturity

Local Volatility models (e.g. Dupire 1993)Stochastic Volatility and Jump-diffusion models (e.g. Merton 1976,

Heston 1993)

S&P500

Page 27: Pavel V. Shevchenko Quantitative Risk Management CSIRO ...lab.datascience.jp/AJF/presentations/Shevchenko.pdf · CSIRO Mathematical & Information Sciences Track Records in Financial

CSIRO Mathematical & Information Sciences www.cmis.csiro.au

Heston stochastic volatility model (1993)

0,)(

;0Im,)(

]0,max[)( payoff optionPut

1,)(

;1Im,)(

],0,max[)( payoff option Call

)( ;)( ;)()(

:approx or PDF Fourier inverse via price Option

)]()()(exp[),,|,,(

ln ),,,|,,(density tionfor transi FunctionsticCharacteri)(

)(

process neutral-Risk

1

21

1

1

21

1

30201000

000

>+

−=<−

−=

−=•

−<+

−=>−

−=

−=•

====

++==

=•

+−=

+−=

∫∫∫∫

−∞

+∞−

+−+

−∞

+∞−

+−+

adkikk

KpPkikk

Kh

SKxh

adkikk

KpCkikk

Kh

KSxh

dxxpepdxxhehdkhpdxxhxpQ

CvCxCdxdvtvxtvxpep

SXtvxtvxpdZVdtVdV

dWVSdtqrSdS

ia

ia

ik

k

ik

k

ia

ia

ik

k

ik

k

ikxk

ikxkkk

ikxk

tttt

ttttt

π

π

τττ

ξθω

Page 28: Pavel V. Shevchenko Quantitative Risk Management CSIRO ...lab.datascience.jp/AJF/presentations/Shevchenko.pdf · CSIRO Mathematical & Information Sciences Track Records in Financial

CSIRO Mathematical & Information Sciences www.cmis.csiro.au

Heston model - Calibration via today’s prices

impl vol vs strike

12.5%

13.5%

14.5%

0.516 0.526 0.536 0.546

observed at 7daysfitted at 7days

impl vol vs strike

12.5%

13.5%

14.5%

0.416 0.516 0.616

observed at 367daysfitted at 367days

impl vol vs strike

12.5%

13.5%

14.5%

0.516 0.526 0.536 0.546

observed at 7days

fitted at 7daysimpl vol vs strike

12.5%

13.5%

14.5%

0.416 0.466 0.516 0.566 0.616 0.666

observed at 367daysfitted at 367days

Constant model parameters, US$/AU$

Time-dependent model parameters, US$/AU$

Page 29: Pavel V. Shevchenko Quantitative Risk Management CSIRO ...lab.datascience.jp/AJF/presentations/Shevchenko.pdf · CSIRO Mathematical & Information Sciences Track Records in Financial

CSIRO Mathematical & Information Sciences www.cmis.csiro.au

Local volatility model, Dupire 1993

volimplied is .

1

22),(

//))()(()(/2),( :function Volatility

0)))()(()),((),,,( :eq Kolmogorov Fwd.

),,,(),,,( :density neutral-Risk

]0,)([)),(())(( :payoff Call

,),,,()(),( :priceoption Vanilla

).(),()]()([)(/)( :process neutral-Risk

2

12

22

2

1

2

2222

2

222

21

2

2

0

θθθθθ

θθθθθσ

σ

σ

σ

⎥⎥⎦

⎢⎢⎣

⎡⎟⎠⎞

⎜⎝⎛∂∂−

∂∂+⎥⎦

⎤⎢⎣⎡

∂∂+

∂∂

++∂∂

=

∂∂∂∂−++∂∂

=

=∂−∂

+∂

∂−

∂∂

∂∂

=

−==

=

+−=

∫∞

TK

dK

TKK

TKd

KTrK

TT

TK

KCKKCTqTrKCTqTCTK

uupTqTr

upuTu

TTutSp

KTKtSCTKtSp

KTSMaxTTSCTSh

duTutSpuhtSQ

tdWtSdttqtrtStdS

Page 30: Pavel V. Shevchenko Quantitative Risk Management CSIRO ...lab.datascience.jp/AJF/presentations/Shevchenko.pdf · CSIRO Mathematical & Information Sciences Track Records in Financial

CSIRO Mathematical & Information Sciences www.cmis.csiro.au

Local volatility model – Exotic Option Pricing

element finite ,difference finite :methods PDENumerical

),()(),())()((),(),(),(

).(),()]()([/]0,max[payoff call e.g.)];(Payoff[),( :price Option

2

222

21 tSQtr

StSQStqtr

StSQStS

ttSQ

tdWtSdttqtrSdSKSSEtSQ

tt

TTt

=∂

∂−+

∂∂

+∂

+−=−==

σ

σ

Page 31: Pavel V. Shevchenko Quantitative Risk Management CSIRO ...lab.datascience.jp/AJF/presentations/Shevchenko.pdf · CSIRO Mathematical & Information Sciences Track Records in Financial

CSIRO Mathematical & Information Sciences www.cmis.csiro.auJoint work with M.Wüthrich (ETH Zurich) and G.Peters (UNSW/CSIRO)

Claims Reserving (non-life insurance), solvency requirements, claims development triangle

Page 32: Pavel V. Shevchenko Quantitative Risk Management CSIRO ...lab.datascience.jp/AJF/presentations/Shevchenko.pdf · CSIRO Mathematical & Information Sciences Track Records in Financial

CSIRO Mathematical & Information Sciences www.cmis.csiro.au

- predictor for and estimator for

Mean Square Error

of Prediction

“best estimate” of reserveBayesian context – variance decomposition

is model parameter vector modelled as random variable

Page 33: Pavel V. Shevchenko Quantitative Risk Management CSIRO ...lab.datascience.jp/AJF/presentations/Shevchenko.pdf · CSIRO Mathematical & Information Sciences Track Records in Financial

CSIRO Mathematical & Information Sciences www.cmis.csiro.au

Claims reserving: Tweedie’s compound Poisson model

Page 34: Pavel V. Shevchenko Quantitative Risk Management CSIRO ...lab.datascience.jp/AJF/presentations/Shevchenko.pdf · CSIRO Mathematical & Information Sciences Track Records in Financial

CSIRO Mathematical & Information Sciences www.cmis.csiro.au

Page 35: Pavel V. Shevchenko Quantitative Risk Management CSIRO ...lab.datascience.jp/AJF/presentations/Shevchenko.pdf · CSIRO Mathematical & Information Sciences Track Records in Financial

CSIRO Mathematical & Information Sciences www.cmis.csiro.au

Claims reserving – expected reserves (ER), process variance (PV), estimation error (ER). Bayesian (MCMC) vs Maximum Likelihood

Page 36: Pavel V. Shevchenko Quantitative Risk Management CSIRO ...lab.datascience.jp/AJF/presentations/Shevchenko.pdf · CSIRO Mathematical & Information Sciences Track Records in Financial

CSIRO Mathematical & Information Sciences www.cmis.csiro.au

Research topics for collaboration

• Combining different data sources: internal & external data with expert opinions (credibility theory, Bayesian techniques)

• Dependence between risks: copula methods, structural models• Expert elicitation (Bayesian networks) • Extreme Value Models (Modelling distribution tail)• Efficient Markov Chain Monte Carlo, ABC MCMC, Monte Carlo, finite

element/finite difference methods • State-space models (Kalman/particle filters/SMC)

• Pattern recognition – trading strategies • Stochastic/local volatility models• Modelling operational/market/credit risks/insurance risks• Pricing exotic options• Modelling commodities, interest rates, • Portfolio asset allocation

Page 37: Pavel V. Shevchenko Quantitative Risk Management CSIRO ...lab.datascience.jp/AJF/presentations/Shevchenko.pdf · CSIRO Mathematical & Information Sciences Track Records in Financial

CSIRO Mathematical & Information Sciences www.cmis.csiro.au

Recent journal publications

• G. W. Peters, P.V. Shevchenko and M.V. Wüthrich (2009). Chain Ladder Method: Bayesian Bootstrap versus Classical Bootstrap. Submitted to Insurance: Mathematics and Economics.

• G. W. Peters, P. V. Shevchenko and M. V. Wüthrich (2009). Model uncertainty in claims reserving within Tweedie's compound Poisson models. ASTIN Bulletin 39.

• P. V. Shevchenko (2008). Implementing Basel II Loss Distribution Approach for operational Risk. Submitted to Applied Stochastic Models in Business and Industry.

• Peters, G., P. Shevchenko and M.Wuthrich (2009). Dynamic operational risk: modelling dependence and combining different data sources of information. J. of Op Risk

• Shevchenko, P. (2008). Estimation of Operational Risk Capital Charge under Parameter Uncertainty. The Journal of Operational Risk 3(1), 51-63.

• Luo, X., P. V. Shevchenko and J. Donnelly (2007). Addressing Impact of Truncation and Parameter Uncertainty on Operational Risk Estimates. The J. of Op. Risk 2(4), 3-26.

• D. D. Lambrigger, P.V. Shevchenko and M. V. Wüthrich (2007). The Quantification of Operational Risk using Internal Data, Relevant External Data and Expert Opinions. J. of Op. Risk 2(3), 3-27.

• Bühlmann,H., P. Shevchenko and M. Wüthrich. A “Toy” Model for Operational Risk Quantification using Credibility Theory. The J. of Operational Risk 2(1), 3-19, 2007.

• Shevchenko, P. and M. Wüthrich (2006). Structural Modelling of Operational Risk using Bayesian Inference: combining loss data with expert opinions. J. of Op. Risk 1(3), 3-26.

www.cmis.csiro.au/Pavel.Shevchenko

Page 38: Pavel V. Shevchenko Quantitative Risk Management CSIRO ...lab.datascience.jp/AJF/presentations/Shevchenko.pdf · CSIRO Mathematical & Information Sciences Track Records in Financial

Thank you

CSIRO Mathematical & Information SciencesPavel Shevchenko

Email: [email protected]/Pavel.Shevchenkowww.csiro.au/people/Pavel.Shevchenko.html