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The Impacts of Animal Disease Crises on the Korean Meat Market. Moonsoo Park Associate Research Fellow Korea Institute for Industrial Economics & Trade Yanhong Jin Assistant Professor of Agricultural Economics Texas A&M University, College Station David A. Bessler - PowerPoint PPT Presentation
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1
The Impacts of Animal Disease Crises on the Korean Meat Market
Moonsoo Park
Associate Research FellowKorea Institute for Industrial Economics & Trade
Yanhong Jin Assistant Professor of Agricultural Economics
Texas A&M University, College Station
David A. Bessler Professor of Agricultural Economics
Texas A&M University, College Station
July, 2008
4
The Unrestricted Vector Autoregression (VAR)
The VAR can be illustrated using a set of m variables each measured at time t; t= 1, 2, 3,…,T:
xt' = (x1t, x2t, x3t, . . . , xmt); t= 1,2,3,…,T .
This vector, xt , can be written as equation (1):
K
(1) xt = Σ α(k)xt-k + et
k=1 Here α(k) is an autoregressive matrix of dimension (mxm) at lag k which
connects xt and xt-k. K is the maximum lag in the VAR. et is a vector residual term of dimension (mx1). The integer K is large enough such that e t is white noise.
5
Analytical Derivation of the MAR The same operations can be done with a vector autoregression. Say we
have a first order vector autoregression (VAR) in two variables x1t and
x21:
We can perform an analytical or a zero/one simulation to derive the MA Representation for this VAR .
t
t
t
t
t
t
e
e
X
X
X
X
,2
,1
1,2
1,1
,2
,1
6.3.
2.9.
6
MAR from the VAR
We can write this in autoregressive form by moving all X’s to the left hand side of the equation.
Solving for the X vector in tems of the innovations:
Unfortunately taking the inverse on the left hand side of this last equation is a difficult task .
t
t
t
t
e
e
X
X
BB
BB
,2
,1
,2
,1]6.3.
2.9.
10
01[
t
t
t
t
e
e
BB
BB
X
X
,2
,11
,2
,1
6.13.
2.9.1
7
Historical Decomposition.
Using the same moving average representation we can study the behavior of a series in a neighborhood of important historical events.
In the example I give below I have fit a VAR to daily stock market data on indexes of return from six markets around the world: Australia, Hong Kong, Japan, Singapore, United Kingdom and the US. I can derive the VARs moving average representation and then partition it in a neighborhood of an historically important date. Here the date is October 19, 1987. The day stock markets around the world
crashed.
8
Partition of MAR by Time Periods
Here we write the vector X in its moving average form.
Where the vector X is written as an infinite series of orthogonalized innovations, et-i. From Equation (3), we can calculate a historical
partition of the vector X at any date T+k into information available at time t = T and information which is revealed at period t = T+1, T+2, … , T+k. We can write the vector X at period T+k as:
)3(0
iti
it eX
)4(][1
0skT
kssskT
k
sskT eeX
9
More on the PartitionThe position of the vector X that is due to information known up to period T is given by the term in brackets (the right-hand-most summation on the right side of the equals sign).Again equation (4) from the previous slide:
Information that is revealed from T+1 to T+k is given by the first summation expression on the right-hand side of the equals sign. Each of these terms ( seT+k-s ) is the product of a matrix (s) and the vector of innovations at period T+k-s (eT+k-s ). The second term on the rhs if (4) is what we call the base (information revealed before of date of interest T.
)4(].[1
0skT
kssskT
k
sskT eeX
][ skTks
se
10
Example: World Stock Market ContagionXHK,T+2 = HK,AUS(0)eAUS,T+2 + HK,AUS(1)eAUS,T+1 [due to Australia]
+ HK,JPN(0)eJPN,T+2 + HK,JPN(1)eJPN,T+1 [due to Japan]
+ HK,HK(0)eHK,T+2 + HK,HK(1)eHK,T+1 [due to Hong Kong]
+ HK,SING(0)eSING,T+2 + HK,SING(1)eSING,T+1 [due to Singapore]
+ HK,UK(0)eUK,T+2 + HK,UK(1)eUK,T+1 [due to U K]
+ HK,US(0)eUS,T+2 + HK,US(1)eUS,T+1 [due to US]
+ baseHK,T
Here we write the value of the Hang Seng Index (Hong Kong) at date T+2 as its moving average representation. This is then decomposed into innovations arising from all other indexes around the world. We can plot each series (XHK,T+k) as well as that part of X at each T+K which is due to shocks in each index (including itself).
11
Several significant animal diseases outbreaks caused
disruption Korean meat market since 2000 FMD (Foot and Mouth Disease) outbreak in April 2000
Total estimated cost: $474 million
AI (Avian Influenza) outbreak in December 2003 Total estimated cost: $ 137 million
BSE discovery in the U.S. in December 2003 Ban import of beef from U.S
Need to investigate quantify the impacts of domestic and
oversea animal disease crises on the Korean meat markets No systematical study for the Korean case
Motivation
12
Investigate in-depth the impacts of multiple disease
outbreaks (domestic and oversea) on Meat prices at different levels of the supply chain
Price margins along the supply chain
Dynamic independence in the meat system
Quantify the relative importance of specific shocks
to each variable along the Korean meat supply
chain
Research Objectives
13
U.K., Europe Burton & Young(1996), Lloyd et al.(2001, 2006), Leeming &
Turner(2004)
U.S, Canada Lusk & Schroeder(2002), Prtchet et al.(2005), Schelenker &
Villa(2006)
Japan
Jin et al.(2003), McCluskey et al.(2005),Peterson and Chen(2005),
Saghaian et al.(2007)
Previous Studies
15
Data source: Korea Agro-Fisheries Trade Corporation
(KAFTC)
Monthly price in meat supply chain
Meat types: beef, pork, chicken
Supply chain levels: Retail, Wholesale, Farm
Study periods: January 1985 to December 2006
Data
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Vector Error Correction Model (VECM)
Forecast future prices using only information known
before the event
Compare forecasted prices with actual prices affected by
all the information including the disease outbreak
Statistical robustness tests for model specification
“Model selection methods” based on information criteria
(Phillips, 1996)
Test for structural change (Hansen and Johansen, 1999)
Forecasting Meat Prices
17
Forecasting (Cont.) Time-varying Rolling Trace test for Structural Change
Detect a significant structural change induced by the 2000 FMD outbreak,
but AI/BSE incidents did not cause significant structural break
The 2000 FMD Outbreak
Forecast prices of 44 months after the outbreak (2000:4—2003:11) using
the data from 1985:1 to 2000:3
The 2003 AI/BSE Events
Forecast prices of 36 months after the outbreak (2004:1—2006:12)
Option 1: Large sample from 1985:1 to 2003:11
Option 2: Small sample from 2000:05 to 2003:11
“Modified DM test" shows option 1 gives better forecasting performance
18
Forecasting (Cont.) Measure the impact of animal disease outbreak
(“size” and “duration” of the shocks) On each price series
On price margins
Widen price margin if PM >0, narrows if PM <0
100
F
FxP d
ij
dij
dijd
ij
FFxxPM dif
dir
dif
dir
drfi ,
FFxxPM dif
diw
dif
diw
dwfi ,
FFxxPM diw
dir
diw
dir
drwi ,
retail-to-farm
wholesale-to-farm
retail-to-wholesale
19
Evaluate how much each price innovation accounts for
the atypical variation of a certain price series due to
animal disease shocks: ““Dynamic price interdependenceDynamic price interdependence””
Identification of contemporaneous causal ordering of
price innovations
Moving Average process:
Historical Decomposition
skT
k
ssskT
ksskTX
1
0
21
Impacts of the 2000 FMD Outbreak on the Meat Prices
Beef Pork Chicken
Decrease beef and pork prices but increase chicken prices Beef sector
Overall, recover back to the pre-event level after 16 months Retail beef price recovered 8 months after the FMD event Wholesale and farm level beef prices recovered 6 or 7 months after the recovery
of the retail price Pork sector
Long term adverse impacts on the farm and wholesale prices: The prices did not fully recover for over 44 months after FMD
Chicken sector Short-run benefit due to the substitution effect
22
Impacts of the 2003 AI/BSE Events on the Meat Prices
Beef Pork Chicken
Beef sector Retail beef price decreased by 10% in the 10th month, rebounded, and recovered
13 months after the incidents Sharp price drop (28% in 6th month) at the farm and wholesale levels wholesale beef recovered after 14 months, farm beef price did not fully recover “Concern of beef safety” may be one of main negative factor
Pork sector Pork market benefited from the outbreak
Chicken sector Negative short-run effect from the incidents
23
Impacts of the 2000 FMD on Price Margins
Price margins of beef and pork at the retail level increased relative to the
farm and wholesale levels, but the price margin between the wholesale and
farm levels stayed the same.
Retailers may gain from the disease outbreaks
The changes of the price margins in the chicken sector are mixed, no
discernable pattern.
Beef Pork Chicken
24
Impacts of the 2003 AI/BSE Events on Price Margins
The price margin of pork and chicken in the retail level gained
relative to the farm and wholesale levels.
The beef price margin increased starting from the 13th month after
the outbreaks.
Beef Pork Chicken
25
Difference Between Both Outbreaks
The BSE outbreak occurred in the oversea market was
greater than that of the domestic FMD outbreak
Initial beef price dropped due to the BSE discovery within the
first six months was much bigger than the FMD outbreak
Price recovery came earlier in the BSE case (13 months after the
BSE and 16 months for the FMD)
FMD negatively affects pork market, but AI/BSE increase
pork prices
26
Information Flows on Meat Prices Contemporaneous Causality from DAG
Retail chicken price
Retail pork price
Retail beef price
Farm chicken price
Farm pork price
Farm beef price
Wholesale chicken price
Wholesale pork price
Wholesale beef price
27
Contribution of Each Price Series on the Innovation of Retail Beef Price
2000 FMD Outbreak 2003 AI/BSE Outbreak
Farm price seems exogenous under both events: Variation of
the farm price was mainly due to the shocks of its own price.
Wholesale price in the 2000 FMD case seems exogenous, but
explained by farm price in the 2003 AI/BSE case.
Farm price played a dominant role in explaining the variation
of the retail prices in both cases.
29
Summary Both domestic and oversee animal disease outbreaks caused
a temporary price shock to the Korean meat market
AI/BSE incidents led to more significant changes in beef
prices compared with the FMD outbreak.
Price margin indicates that both outbreaks triggered
asymmetric price transmission: Retail sector had a windfall
price gain.
Innovation of farm price has played a major role in
explaining the innovations of the wholesale and retail prices.