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Jumps in Soybean Prices
Evidence and Applications
Quant Team
Ruchi Agri-Trading
Singapore
April 24, 2013
Overview
Objective
Introduction
Model Description
Data and Model Estimation
Estimation Results
Applications
Objective
To study and model Dynamic behaviour of daily soybean
prices by 鍖nding strong evidence for conditional
volatility(GARCH) and conditional jump behaviour.
To use modeling framework for simulations and Option pricing
in a trading environment.
Introduction
Q:What are volatility models?
A:Models used to forecast and measure volatility.
Introduction
Simplest Model : Equally weighted volatility
rt is the excess return,
2
t =
1
N + 1
N
j=0
r2
tj
1) all observations from t-N to t are given equal weight
2) all observations before t-N are given no weight
3) the choice of N is left to the trader.
Clustering in Financial Time Series
Introduction
GARCH
GENERALIZED - more general than ARCH model
AUTOREGRESSIVE-depends on its own past
CONDITIONAL-variance depends upon past information
HETEROSKEDASTICITY- fancy word for non-constant
variance
rt = ht t
GARCH(1, 1) where t N(0, ht)
ht =  + 硫ht1 + 留r2
t1
a constant variance
yesterdays forecast
yesterdays news
Introduction
GARCH-JUMP model
Q:Why incorporate Jumps in GARCH?
A1:There is empirical evidence of jumps in both returns and
volatility.
A2:An innovation/news may arrive in a way which cannot be
modelled completely within traditional GARCH framework
Introduction
GARCH-JUMP model
Q:How to incorporate Jump?
A:Compound Poisson process
Q:What does this mean?
Jumps arrive randomly
Size of jumps is also random :
J(了, 慮, 隆2
)
where :
了 is jump intensity or expected number of jumps on a given
day
慮 is the mean jump size
隆 is the variance of jump size
Model Description: DVDJ Model
Daily Return Dynamics
Rt+1  log
St+1
St
= r +(了z 
1
2
)hz,t+1 +(了y 両)hy,t+1 +zt+1 +yt+1
Where
St+1 denotes asset price at close of day t + 1
r denotes risk free rate
zt+1 denotes normal component of daily shocks distributed as
N(0, hz,t+1)
yt+1 denotes jump component of daily shocks distributed by a
compound Poisson process J(hy,t+1, 慮, 隆2)
(了z  1
2) and (了y  両) are mathematical adjustments
required for option pricing
Model Description: DVDJ Model
Daily Variance Dynamics
hz,t+1 = wz + bzhz,t +
az
hz,t
(zt  czhz,t)2
+ dz(yt  ez)2
Daily Jump Intensity
hy,t+1 = wy + by hy,t +
ay
hz,t
(zt  cy hz,t)2
+ dy (yt  ez)2
Total variance of Rt+1 is given by:
Variance(Rt+1) = hz,t+1 + (隆2
+ 慮2
)hy,t+1
Data and Model Estimation
We estimate our model using CBOT Soybean November
futures for last 20 years(1993-2012)
We cut o鍖 each series 20 trading days before expiry
Each future series contributes 1 year daily prices
Model requires estimation of 11 parameters:
Parameters of the GARCH [了z , 了y , wz , b, a, c, d, e]
Parameters of the jump [wy ,慮, 隆]
Model is estimated using optimization of standard maximum
likelihood
Estimation and Results
Table 1 : DVDJ Model- GARCH Parameters
了z 了y wz b a c d e
1.9707 -0.0046 -5.6069e-06 0.9780 8.6808e-06 -11.333 0.0670 -0.0012
Table 2 : DVDJ Model -Jump Parameters
wy 慮 隆
0.0909 -0.0022 0.0218
Table 3 : LogLikihood(lower is better)
GARCH(1,1) DVDJ Model
-14201.66 -15217.42
Table 4 : Vol properties
AVG. Annual Vol-GARCH(1,1) AVG. Annual-Vol DVDJ Model Normal Comp of Vol Jump Comp of Vol
20.67 % 21.1 % 84.03% 15.97%
Estimation and Results
SX 12: DJI Model Vol
Estimation and Results
SX 12: DJI vs GARCH(1,1) Vol Comparison
Estimation and Results
SX 12: Expected number of jumps
Estimation and Results
Contribution of Jump Component to Returns
Estimation and Results
2008 vs. 2012
Application
Option Pricing
Application
Option Pricing
Application
Simulation Framework
To ex-Ante predict impact of information based jump on
Volatility
A full probability model to incorporate known information to
provide more accurate con鍖dence intervals
VaR Calculation
Stress and Scenario Testing

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Dynamic Jump Intensity Dynamic GARCH Volatility

  • 1. Jumps in Soybean Prices Evidence and Applications Quant Team Ruchi Agri-Trading Singapore April 24, 2013
  • 2. Overview Objective Introduction Model Description Data and Model Estimation Estimation Results Applications
  • 3. Objective To study and model Dynamic behaviour of daily soybean prices by 鍖nding strong evidence for conditional volatility(GARCH) and conditional jump behaviour. To use modeling framework for simulations and Option pricing in a trading environment.
  • 4. Introduction Q:What are volatility models? A:Models used to forecast and measure volatility.
  • 5. Introduction Simplest Model : Equally weighted volatility rt is the excess return, 2 t = 1 N + 1 N j=0 r2 tj 1) all observations from t-N to t are given equal weight 2) all observations before t-N are given no weight 3) the choice of N is left to the trader.
  • 7. Introduction GARCH GENERALIZED - more general than ARCH model AUTOREGRESSIVE-depends on its own past CONDITIONAL-variance depends upon past information HETEROSKEDASTICITY- fancy word for non-constant variance rt = ht t GARCH(1, 1) where t N(0, ht) ht = + 硫ht1 + 留r2 t1 a constant variance yesterdays forecast yesterdays news
  • 8. Introduction GARCH-JUMP model Q:Why incorporate Jumps in GARCH? A1:There is empirical evidence of jumps in both returns and volatility. A2:An innovation/news may arrive in a way which cannot be modelled completely within traditional GARCH framework
  • 9. Introduction GARCH-JUMP model Q:How to incorporate Jump? A:Compound Poisson process Q:What does this mean? Jumps arrive randomly Size of jumps is also random : J(了, 慮, 隆2 ) where : 了 is jump intensity or expected number of jumps on a given day 慮 is the mean jump size 隆 is the variance of jump size
  • 10. Model Description: DVDJ Model Daily Return Dynamics Rt+1 log St+1 St = r +(了z 1 2 )hz,t+1 +(了y 両)hy,t+1 +zt+1 +yt+1 Where St+1 denotes asset price at close of day t + 1 r denotes risk free rate zt+1 denotes normal component of daily shocks distributed as N(0, hz,t+1) yt+1 denotes jump component of daily shocks distributed by a compound Poisson process J(hy,t+1, 慮, 隆2) (了z 1 2) and (了y 両) are mathematical adjustments required for option pricing
  • 11. Model Description: DVDJ Model Daily Variance Dynamics hz,t+1 = wz + bzhz,t + az hz,t (zt czhz,t)2 + dz(yt ez)2 Daily Jump Intensity hy,t+1 = wy + by hy,t + ay hz,t (zt cy hz,t)2 + dy (yt ez)2 Total variance of Rt+1 is given by: Variance(Rt+1) = hz,t+1 + (隆2 + 慮2 )hy,t+1
  • 12. Data and Model Estimation We estimate our model using CBOT Soybean November futures for last 20 years(1993-2012) We cut o鍖 each series 20 trading days before expiry Each future series contributes 1 year daily prices Model requires estimation of 11 parameters: Parameters of the GARCH [了z , 了y , wz , b, a, c, d, e] Parameters of the jump [wy ,慮, 隆] Model is estimated using optimization of standard maximum likelihood
  • 13. Estimation and Results Table 1 : DVDJ Model- GARCH Parameters 了z 了y wz b a c d e 1.9707 -0.0046 -5.6069e-06 0.9780 8.6808e-06 -11.333 0.0670 -0.0012 Table 2 : DVDJ Model -Jump Parameters wy 慮 隆 0.0909 -0.0022 0.0218 Table 3 : LogLikihood(lower is better) GARCH(1,1) DVDJ Model -14201.66 -15217.42 Table 4 : Vol properties AVG. Annual Vol-GARCH(1,1) AVG. Annual-Vol DVDJ Model Normal Comp of Vol Jump Comp of Vol 20.67 % 21.1 % 84.03% 15.97%
  • 14. Estimation and Results SX 12: DJI Model Vol
  • 15. Estimation and Results SX 12: DJI vs GARCH(1,1) Vol Comparison
  • 16. Estimation and Results SX 12: Expected number of jumps
  • 17. Estimation and Results Contribution of Jump Component to Returns
  • 21. Application Simulation Framework To ex-Ante predict impact of information based jump on Volatility A full probability model to incorporate known information to provide more accurate con鍖dence intervals VaR Calculation Stress and Scenario Testing