Transcript Slide 1

Information Transmission in Technology Diffusion:
Social Learning, Extension Services
and Spatial Effects in Irrigated Agriculture
Associate Prof. Phoebe Koundouri
Director of RESEES [Research tEam on Socio-Economic Sustainability]
ATHENS UNIVERSITY OF ECONOMICS & BUSINESS
Visiting Senior Research Fellow
Grantham Research Institute on Climate Change and the Environment
LONDON SCHOOL OF ECONOMICS & POLITICAL SCIENCE
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Co-Authors:
• Margarita Genius, Department of Economics, University of Crete.
• Celine Nauges, Toulouse School of Economics and the University of
Queensland.
• Vangelis Tzouvelekas, Department of Economics, University of Greece.
We acknowledge the financial support of the European Union FP6 financed
project FOODIMA: Food Industry Dynamics and Methodological
Advances (Contract No 044283). www.eng.auth.gr/mattas/foodima.htm.
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Keywords:
•
agricultural technology adoption and diffusion
•
information transmission
•
social learning and social networks
•
extension services
•
dynamic maximization behavioral model under uncertainty
•
risk preferences
•
factor analytic model
•
flexible method of moments
•
duration analysis
•
olive farms
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Aim and Contribution
• To investigate the role and sources information transmission in promoting
irrigation technology adoption and diffusion (TAD) with socioeconomic,
production risk , environmental & spatial considerations .
• Why irrigation technology? Central to increasing water use efficiency,
economizing on scarce inputs, maintaining current levels of farm
production, particularly in semi-arid & arid areas [CAP, WFD, etc.]
• Structure of Work and Methods:
- dynamic maximization behavior model
- econometric duration analysis model merged with:
- factor analysis for identification of info transmission paths and peers
- flexible method of moments for risk attitudes estimation
- applied to micro-dataset olive farms in Crete
• Findings: both extension services and social network are strong
determinants of TAD, while the effectiveness of each type of informational
channel is enhanced by the presence of the other. Policy Implications!
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BACKGROUND LITERATURE
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Several empirical studies, in developed & developing
countries, on modern irrigation TAD patterns:
e.g. Dinar, Campbell and Zilberman AJAE 1992
Dridi and Khanna AJAE 2005
Koundouri, Nauges and Tzouvelekas AJAE 2006, etc.
Evidence that:
• economic factors: e.g. water and other input prices, cost of irrigation
equipment, crop prices
• farm organizational and demographic characteristics: e.g. size of farm
operation, educational level, experience
• risk preferences with regards to production risk
• environmental conditions: e.g. soil quality, precipitation, temperature
…matter in explaining TAD.
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…also TAD patterns are conditional on knowledge
about new technology:
• Besley and Case AER 1993
• Foster and Rosenzweig JPE 1995
• Conley and Udry AER 2010, etc.
Sources of Information and Knowledge:
- Extension Services (private or public).
World Bank: Rivera & Alex 2003; World Bank 2006; Birkhaeuser et al. 1991
Usually ES target specific farmers who are recognized as peers.
- Social Learning:
Rogers 1995: via peers (homophilic or heterophilic neighbors).
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Peers: farmers exerting a direct or indirect influence
on the whole population of farmers in their respective areas.
Homophilic
Farmers exchange information and learn
from individuals with whom they have
close social ties and with whom they
share common professional or/and
personal characteristics (education, age,
religious beliefs, farming activities etc.)
Heterophilic
Farmers may also follow or trust the
opinion of those that they perceive as
being successful in their farming
operation, even though they
occasionally share quite different
characteristics.
Measuring the extent of information transmission via different
channels & identifying its role in TAD is difficult:
1. Set of peers difficult to define (Maertens and Barrett AJAE 2013): we need
to go beyond the simplistic definition of peers as (physical) neighbors.
2. Distinguishing learning from other phenomena (interdependent preferences
& technologies; related unobserved shocks) that may give rise to similar
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observed outcomes is problematic (Manski RES 1993).
THEORETICAL MODEL
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Farmers decision to invest in a new irrigation technology (NIT).
NIT improves irrigation effectiveness (shift in the production technology).
Expected efficiency gains are uncertain at adoption decision time.
Uncertainty can be reduced via accumulation of knowledge:
- Extension Services, before and after adoption
- Social Networks, before and after adoption
- Learning-by-doing /using, after adoption
At each time period the farmer decides whether to adopt by comparing :
- Expected Cost of adoption (decreasing function of time)
- Expected benefit of adoption depending on information transmission &
accumulation, socio-economic (including risk attitudes) & environmental
characteristics
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Farm's j technology, continuous twice-differentiable concave production function:
y j f
x vj , x w
j , Aj  #
yj: crop production
xjv : vector of variable inputs (labor, pesticides, fertilizers, etc.)
xjw: irrigation water
x jw < x w
min , risk of low (or negative) profit in case of water shortage.
Adoption allows hedging against the risk of drought and consequent profit loss.
Aj : technology index: irrigation effectiveness index:
(water used by crop)/(total water applied in field)
Aj⁰ with conventional technology
Aj* with new technology farmer produces same y using same xv and lower xw.
Aj = Aj* : max irrigation effectiveness is reached
Aj* > Aj⁰ : max irrigation effectiveness cannot be reached with Aj⁰
May require time before the new technology is operated at A*.
A j,st, : the expected, at time s, efficiency index for t, under the assumption the
new technology is adopted at time τ.
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c, 
c j,t /
t 0 : fixed cost of NIT known at period t.
Modeling the timing of Adoption
s  0, 1, 2, . . . , T 1,  s 1,  , T, t  
, 1, 2, . . . , T
τ
s
0
Info
gathering
period
s+1
Info
gathering
period
τ+1 s + 2
Info
gathering
period
Fixed time
………………………………… horizon
T
τ (adoption time)
t (time)
E(Profit)
for t until T
E(Profit)
for t until T
E(Profit)
For t until T
Decision:
Adopt
or Not
Decision:
Adopt
or Not
Decision:
Adopt or
Not
………………………..
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Expected Discounted Profit Functions:
- p, ww , wv : expected discounted crop, irrigation water, variable input prices (assumed
dynamically constant by farmer).
-positively linearly homogeneous and convex in p, wv, and ww
-non-decreasing in crop price and irrigation technology index
-non-increasing in variable input and irrigation water prices.
v
w
v v
w w
p, w v , ww , Aj max

pf
x
,
x
,
A

w
x
w
xj 
j
j
No Adoption during t: 
j
j
j
x v ,x w
Adoption at τ: s,,t p,w
v
v
w
v v
w w
,ww ,As t, max

pf
x
,x
,A

t,


w
x
w
x s,,t .
s
s,,t s,,t
s,,t
v w
x ,x
Farmer max over τ her temporal aggregate discounted profit:


T e 1 
T


1
V s,,T :

ts
1


T

s

c s,
t

t1


T e 1 
T





1 s
c s,
T e 1T1

s



T 
T e 1T
 0



1 s 
T 
T e 1T
 0




T e 1T1

s c s, 
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#
Farmer’s Trade-off :
Benefit: Delaying investment by one year allows the farmer to
purchase the modern irrigation technology at a reduced cost.
Cost: Delaying adoption by one year results in producing with the
conventional less efficient technology and bearing a higher risk of
water shortage (thus a loss in expected profit).
Note: Farmer considers that technology efficiency index will remain constant after
adoption because she does not have enough information to predict the
evolution of the technology efficiency after adoption (which is a complex
function of learning from others and learning-by-doing).
The model could be extended to allow for the farmers anticipating learning
after adoption. Such an extension would need to incorporate assumptions about
farmer-specific learning curves, which will differ between adopters based on
initial adoption time and farmer-specific socio-economic characteristics.
Such an extension does not alter the learning processes of our model, neither
before, nor after adoption, but it does make the first order conditions less clear.
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Adoption Decision:
Expected Discounted Equipment Cost:
•
At any point in time, s, farmer j assumes a rate of decrease for the discounted
equipment cost:
c s,sk 
1 a s e c,s k1
c s
•
•
as, c,s 0
c s,sk is a decreasing value of k, and converges to c 
s , the asymptotic
discounted equipment cost for farmer j at time s, as k→∞.
Adoption Equation:

c s,s1 c s 
.
s c,s 
The quantity c s,s1 c s represents approximately the expected excess
discounted cost, between choosing to adopt the new technology at time s+1,
namely, as soon as possible, and postponing the adoption for a very long
period, namely, for a period where the rate of decrease of the equipment cost is
practically zero.
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Heterogeneity of Adoption Decision
Deriving from heterogeneity in E(π), which derives from:
•
Farm-specific expected cost for technology and farm-specific Water Efficiency Index,
depending on farm specific Knowledge Accumulation Via:
extension services before and after adoption
social learning before and after adoption
learning by doing after adoption
•
Farm Specific Knowledge Accumulation depends on
socioeconomic characteristics (age, education, experience)
farm location
identification & behavior of influential peers
•
Farm-specific characteristics
input & output prices
risk preferences
spatial location
environmental conditions (defining min water crop requirements)
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Incorporating Risk Attitudes in the Analysis
Endogenous Technology Adoption Under Production Risk:
Theory and Application to Irrigation Technology
Koundouri, Nauges, Tzouveleka2, AJAE 2006
Investigate the microeconomic foundations of technological adoption under
production risk and heterogeneous risk preferences.
Methodology:
- Construct theoretical model of adoption by risk-averse agents under production risk
- Approximate it with flexible empirical model based on higher-order moments of
profit.
- Derive risk preference from estimation results.
- Use risk preferences to explain adoption through a discrete choice model.
Results:
- Risk preferences affect the prob. of adoption: evidence that farmers invest in new
technologies as a means to hedge against input related production risk.
- The option value (value of waiting to gather better information) of adoption,
approximated by education, access to information & extension visits, affects the
prob. of adoption.
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Technology Choice Depends:
input & output prices
agent 
s characteristics
fixed cost of the new technology
utility function
: U
.
production function
distribution of risk
Deriving an analytical solution is problematic!
: f
.
: G
.
Antle (1983, 1987): max E[U(π)] is equivalent to max a function of moments
of the distribution of ε (=exogenous production risk), those moments having X
as arguments. Agent's program becomes:
max E
U


 F
1 
X
, 2 
X
, . . . , m 
X

X
where j , j 1, 2, . . . , m is the m th moment of profit
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Taking a Taylor approximation of
E
U



, the FOC of the max problem:

1 
X


X 
F
X
/
2 
X

1/2! 2


Xk

Xk

F
X
/
1 
X


X 
F
X
/
3 
X

1/3! 3


Xk

F
X
/
1 
X

m 
X 
F
X
/
m 
X
. . . 
1/m!


Xk

F
X
/
1 
X
k 1, . . . , K 
inputs
The following model is estimated for each
k:

1 
X

2 
X

3 
X

m 
X
 1k 2k
3k

...
mk
u k

Xk

Xk

Xk

Xk
where : 2k a 2k 
1/2!
, 3k a 3k 
1/3!
, . . . , mk a mk 
1/m!
: a jk 

F
X
/
j 
X
/

F
X
/
1 
X



1 
X
:

Xk

2 
X
:

Xk

3 
X
:

Xk
a mk :
marginal contribution of input
k
to expected profit
marginal contribution of input
k
to varaince
marginal contribution of input
k
to skewness
weight attributed by farmer to the
mth
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moment of profit
Estimation Procedure:
1) Estimate conditional expectation of profit using a quadratic functional form: total observed
profit is regressed on all levels, squared and cross-products of input expenditures.
2) Use residuals to compute conditional higher moments, which are regressed on all levels,
squared and cross-products of input expenditures.
3) Compute analytical expressions for derivatives of these moments with respect to each
input.
4) Fit 2SLS of the estimated derivative of the expected profit on derivatives for higher
moments.
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Linking Estimated Parameters with Risk Theory:
1. Arrow-Pratt (AP) Absolute Risk Aversion:
ve if risk averse agent (agent’s welfare is negatively affected by higher variance of returns)

FX/
2 X
EU 
APk  

22k

FX/
1 X
EU 
2. Down-side (DS) Risk Aversion:
ve if agent is averse to DS risk (agent’s welfare is negatively affected by situations, which
offer the potential for substantial gains, but which also leave him slightly vulnerable to losses
below some critical level)
FX/
3 X
EU  
DS k 

63k

FX/
1 X
EU  
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4. kspecific Risk Premium (RP):
The larger amount of money the agent is willing to pay to replace the random vaiable by its
expected value E
, which is a monetary measure of the implicit cost of private risk
bearing.
ve if risk averse agent (concave utility function)
Generalizing Pratt (1964)
APk
DS k
RPk 2
3
2
6
: where 2 , 3 are measures of 2nd & 3rd moments, respectively.
22
SURVEY DESIGN &
DATA DESCRIPTION
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• Survey carried out in Crete during the 2005-06 cropping period.
• Part of EU funded Research Program FOODIMA.5
• Agricultural Census (Greek Statistical Service) used to select a random sample of
265 olive-growers located in the four major districts of Crete.
• Farmers were asked to recall:
- time of adoption (drip or sprinklers)
- variables related to their farming operation on the same year (: production patterns,
input use, gross revenues, water use and cost, structural and demographic
characteristics).
• A pilot survey showed that none of the surveyed farmers had adopted before 1994.
• Interviewers asked recall data for the years 1994-2004 (2004 being the last cropping
year before the survey was undertaken).
•
All information was gathered using questionnaire-based interviews undertaken by
the extension personnel from the Regional Agricultural Directorate.
• Out of the 265 farms in the sample, 172(64.9%) have adopted drip irrigation
technology between 1994 and 2004.
24
25
Table 1: Definitions and Summary of the Variables (cont.)
26
The variable of interest in empirical application is the length of time
between the year of drip irrigation technology introduction (1994)
and the year of adoption. Mean adoption time is 4.68 years in our
sample.
27
Production Risk &
Moments of Profit Distribution
• In order to capture the impact of this uncertainty on farmers' adoption
decision we follow Koundouri, Nauges, and Tzouvelekas (2006) utilizing
moments of the profit distribution as determinants of adoption.
• Using recall data on:
- olive-oil revenues
- variable inputs (labor, fertilizers, irrigation water, pesticides)
- fixed (land) input
• Estimated the linear profit function:
i 2.341 0.657 p Oi 0.321 wLi 0.107 wFi 0.076 wWi 0.034 wPi 0.431 x Ai u i
0.423
0.104
0.098
0.054
0.032
0.021
0.125
The residuals have been used to estimate the kth central moments (k=1,…,4) of farm profit
conditional on variable and fixed input use.
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Measurement of Information Transmission
• Each farmer provided information on:
- number of extension visits on her farm prior to the year of adoption
- age and educational level of her peers (according to farmer)
• Data on farm location:
-geographical distance between the farmer and extension agencies
- geographical distance between farmers and her peers
29
Measurement of Information Transmission
• Stock: stock of adopters on the year the farmer adopted
• HStock: stock of homophilic adopters (farmers in same age group (6 year range)
and with similar education levels (2 year range)).
• RStock: stock of homophilic adopters as identified by the farmer (computed as
stock of homophilic adopters among those identified by farmer as belonging to
his reference group).
• Dista : average distance to adopters
• HDista: average distance to homophilic adopters
• RDista : average distance to homophilic adopters as identified by the farmer
• Ext : no. on-farm extension visits until the year of adoption
• Hext: no. on-farm extension visits to homophilic farmers
• RExt : no. on-farm extension visits to homophilic adopters as identified by the
farmer
• Distx : distance of the respondent to the nearest extension agency
• HDistx : average distance of homophilic farmers to the nearest extension agency
• RDistx : average distance of homophilic adopters as identified by farmer, to the
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nearest extension outlet
31
ECONOMETRIC MODEL :
DURATION ANALYSIS & FACTOR ANALYSIS
& FLEXIBLE METHOD OF MOMENTS
32
Duration Model of Adoption and Diffusion
Survival models in statistics relate the time that passes before some event occurs to one or more
covariates that may be associated with that quantity of time.
Duration model formulated in terms of conditional probability of adoption at a particular period,
given that adoption has not occurred before and given farmer-specific information channels,
socioeconomic (& risk attitudes), environmental &spatial characteristics.
T : duration, 
ve RV with f
tcontinuous prob. density function
t
F
t  f
s
ds P
T t: cumulative distribution function
0
t

0
t
S
t1 F
t1  f
s
ds   f
s
ds : survival function
Prob. of survival (of old technology) beyond t
1 S
t: prob. farmer adopts by t
1 S
t: E
Innovation Diffusionshare of adopting farmers
h
t: hazard function (rate), rate at which individuals will adopt the
technology in period t, conditional on not having adopted before t:
f
t
F
t F
t
h
tlim

0
S
t
S
t
33
empirical counterpart of adoption equation from theoretical model.
Empirical Hazard Function
• Assume T follows a Weibull distribution the hazard function is:
h
t, zit , ,  t 1 
it 
•
•
•
•
•
•
α : scale parameter
α > 1: hazard rate increases monotonically with time
α < 1: hazard rate decreases monotonically with time
α = 1: hazard rare is constant
it expzit 
vector zit : variables that determine farmers' optimal choice
Some vary only across farmers (e.g. soil quality and altitude) other vary
across farms and time (e.g. cost of acquiring the new technology)
• β : corresponding unknown parameters
34
Marginal Effects on Hazard Rate and Adoption Time
Set of unknown parameters can be estimated by maximum likelihood
techniques.
Log-likelihood has to account for right-censoring: at time of survey, not
all farmers have adopted the modern technology (d i 0 if ith is
censored):
N
N
i1
i1
LnL
,   d i lnht, z it ,  lnSt, z it , 
Mean expected survival time (
.  Gamma function):
E
t 1  1 1

it
Marginal effects of the k th continuous explanatory variable on hazard
rate and mean expected survival time:

z it 

h
t,
z
,


h
t,
z
,






it
it
zk

zk
E
t
zk 

z it 

E
t

zk
35
Factor Analysis:
Identification Peers and Information Transmission Paths
Peers are not JUST physical neighbors!
• Statistical method used to describe variability among observed,
correlated variables, in terms of a potentially lower number of
unobserved variables, called factors.
• The observed variables are modeled as linear combinations of the
potential factors, plus error terms.
• The information gained on interdependencies between observed
variables is used later to reduce the set of variables in a dataset.
• Estimated Factors will be included in vector zit in our empirical
hazard function.
36
SOCIAL NETWORK CHANNEL: Observable Indicators for Latent Variable 1:
Total no. of adopters in farmer's reference group
•
•
•
•
•
•
Stock: stock of adopters on the year the farmer adopted
HStock: stock of homophilic adopters (farmers in same age group (6 year range) and with
similar education levels (2 year range)).
RStock: stock of homophilic adopters as identified by the farmer (computed as stock of
homophilic adopters among those identified by farmer as belonging to his reference group).
SOCIAL NETWORK CHANNEL: Observable Indicators for Latent Variable 2:
Distance of farmer to adopters in her reference group
Dista : average distance to adopters
HDista: average distance to homophilic adopters
RDista : average distance to homophilic adopters as identified by the farmer
EXTENSION SERVICES CHANNEL: Observable Indicators for Latent Variable 3:
Overall exposure to extension Services
•
•
•
Ext : no. on-farm extension visits until the year of adoption
Hext: no. on-farm extension visits to homophilic farmers
RExt : no. on-farm extension visits to homophilic adopters as identified by the farmer
•
•
•
EXTENSION SERVICES CHANNEL: Observable Indicators for Latent Variable 4:
Distance of farmer to Extension Agencies
Distx : distance of the respondent to the nearest extension agency
HDistx : average distance of homophilic farmers to the nearest extension agency
37
RDistx : average distance of homophilic adopters as identified by farmer, to the nearest EA
Empirical Factor Analytic Model
• Aim: To proxy 4 latent variables using the 12 observable indicators:
x   v
x : the vector of 12 observable indicators
: latent components, (4x1) random vector with zero mean and
variance-covariance matrix I
μ : vector of constants corresponding to the mean of x
Γ : (12x4) matrix of constants
v: (12x1) random vector with zero mean and variance-covariance
21 212 
matrix  diag
Factor analytic model estimated using principal components method
with varimax rotation.
[From the perspective of individuals varimax seeks a basis that most economically
represents each individual: each individual can be well described by a linear
combination of only a few basis functions.]
38
Note: Estimation of Factor Analytic Model
• Principal component analysis (PCA):
Mathematical procedure: uses an orthogonal transformation to convert a set of
observations of correlated variables into a set of values of linearly uncorrelated
variables called PCs. (no. PCs ≤ no. of original variables.
• Varimax Rotation: maximizes the sum of squared correlations between
variables and factors. Achieved if:
(a) any given variable has a high loading on a single factor but near-zero loadings
on the remaining factors
(b) any given factor is constituted by only a few variables with very high loadings
on this factor, while the remaining variables have near-zero loadings on this factor.
•
If these conditions hold, the factor loading matrix is said to have simple structure,
and varimax rotation brings the loading matrix closer to such simple structure.
•
From the perspective of individuals varimax seeks a basis that most economically
represents each individual: each individual can be well described by a linear
combination of only a few basis functions.
39
Estimation of Factor Scores
to be incorporated in Hazard Function
• All pair-wise correlations between the 12 observed InfoVar are
significant at the 0.01 level
• All 12 InfVar are used in order to predict each of the four
latent variables
• Assuming multivariate normality of observable indicators and
ξi, we estimate factors scores ξmi, m=1,…,4, for the ith farmer
(s = 12 InfVar):
E
mi |x is 
40
Table 3: Estimation Results of the Factor Analytic
Model for Informational Variables
41
Estimation of Proportional Hazard Model
(:effect of a unit increase in a covariate is multiplicative with respect to the hazard rate)
it exp0 1 Age it 2 Age 2it 3 Educ it 4 Educ 2it 5 Cost it 6 Fsize it 7 Dens
4
4
k1
m1
8 w Wit 9 p Oit 10 Ard it 11 Alt i 12 Soilsl,i  k Mkit  m mit 5 1
Using regression calibration we approximate :
E exp  j j zoj  k k Mk  m m m 5 1 3
By:
exp  j z oj  k M k  m E m |z oj , M k , x s 5 E 1 3 |z oj , M k , x s
j
k
m
Assume the 4 latent variables, conditional on 12 InfoVar are
uncorrelated with the explanatory variables, E
m |z oj , M k , x s E
m |x s 
,
the estimated factor scores can be used in the hazard function.
42
EMPIRICAL RESULTS &
POLICY IMPLICATIONS
43
Empirical Analysis
•
•
•
•
Sample of 265 randomly selected olive-growing farms in Crete, Greece.
Estimate higher moments of profit (FMM).
Estimate factor scores (PCA & varimax rotation).
Merge profit moments & factor scores in hazard function and estimate a duration
model (right censored ML)
• Consistent standard errors via stationary bootstrapping (Politis & Romano 1994)
• Empirical Results:
- Determination of diffusion curve of modern irrigation technology
- Insights on impact on diffusion process & adoption time of:
• information and learning channels
• risk preferences
• other socio-economic factors
• environmental and spatial characteristics
-ve coefficient implies a negative marginal effect on duration time before adoption: faster
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adoption.
45
46
Note: Estimation Robustness Check
• Estimation of hazard function including (model A.1) & excluding 4 latent
variables (model A.2).
• All key explanatory variables in both models are found statistically
significant.
• Signs of estimated parameters remarkably stable between models
• Reduced model underestimates the effects of age and tree density on mean
adoption time while it overestimates the effect of education, crop price, and
mean profit.
• Akaike and the Bayesian information criteria indicate that the full model is
more adequate in explaining variability in farmers' adoption times.
• Predicted mean adoption times are not statistically different: 5.76 and 5.74
in the full and reduced model.
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Discussion of Results I : Epidemic Effects
Scale parameter of the Weibull hazard function is statistically
significant and well above unity in both models.
Endogenous learning as a process of self-propagation of information
about the new technology that grows with the spread of that
technology:
a) the pressure of social emulation and competition: not highly
relevant for farming business
b) learning process and its transmission through human contact:
captured explicitly via the latent information variables
c) reductions in uncertainty resulting from extensive use of the new
technology: learning-by-doing effects
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Empirical Results II : Extension & Social Learning
•
•
EXTENSION SERVICES
Exposure to extension services
induces faster adoption (-0.306
years).
The bigger the distance from
extension outlets the shorter the
time before adoption (- 0.0531)
Extension agents primarily targeting
farmers in remote areas, as these
farmers are less likely to visit
extension outlets.
•
•
SOCIAL LEARNING
Larger stock of adopters in the
farmer's reference group induces
faster adoption (-0.293 years).
Greater distance between adopters
increases time before adoption
(0.172 years).
The impact of social learning is comparable to the impact of information
provision by extension personnel (mean marginal effects on adoption times
are -0.293 and -0.306 for the stock of adopters and exposure to extension
services, respectively).
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Empirical Result III:
Complementarity of Information Channels
• Interaction term between the two channels of information transmission is
statistically significant and negative: complementarity.
• The passage of information cannot be made ONLY by using rules of thumb
(manuals and blueprints) mainly utilized by extension personnel, but
instead it also requires strong social networks between olive-growers
already engaged in learning-by-doing.
• The complementarity between the two communication channels in
enhancing technology diffusion points to the need of redesigning the
extension provision strategy towards internalizing the structure and
effects of farmers' social networks.
50
Empirical Result IV: Human Capital Variables
Significant Impact of AGE & EDUCATION
• The marginal effect of farmer's age on adoption time is -0.010 years
Time before adoption of drip irrigation technologies decreases with age up
to 60 years (experience effect) and then follows an increasing trend
(planning horizon effect).
• Time until adoption increases with education whenever education level is
less than 9 years (elementary schooling).
For more than 9 years of education, higher educational levels lead to faster
adoption rates: only highly educated farmers are more likely to benefit
from modern technologies.
51
Empirical Result V: Risk Attitudes
Important Determinants of Adoption Behavior
• Expected profit and profit variance are highly significant. I.e. higher
expected profit & higher variance of profit induce faster adoption.
• Olive-growers in Crete are risk averse and adversely affected by a high
variability in returns.
• The adoption of the modern irrigation technology allows these farmers to
reduce production risk in periods of water shortage (confirms Koundouri et
al. 2006 & Groom et al. 2008).
• 3rd & 4th moments of profit insignificant: farmers are not taking downside
yield uncertainty into account when deciding whether to adopt new
irrigation technology.
52
Empirical Result VI:
Environmental Variables, Input & Output Prices,
Important Determinants of Adoption Behavior
• Adverse weather conditions induce faster irrigation technology
adoption (magnitude of the effect is small).
• Olive farms with high tree density are adopting faster than farms
engaged in more extensive olive tree cultivation.
• An increase of one euro cent in the water price has a very significant
effect on both the hazard and the mean adoption time, speeding up
the diffusion of new irrigation technology (0.145 and -0.95,
respectively): Efficient water pricing important
• Higher crop price delays adoption rates (marginal effect is 0.343
years) as farmers have reduced incentives to change irrigation
practices as means of increasing farms expected returns.
53
Policy Recommendations
PR1: Provision of extension services more effective speeding up the adoption process
in areas where there is already a critical mass of adopters.
PR2: Spatial dispersion of extension outlets could also be designed away from market
centers in a way that allows minimization of the average distance between outlets
and peer farms in remote areas.
PR3: Nature of extension provision should be redesigned taking into account its
complementarity with farmers' social networks.
PR4: Efficient pricing of agricultural inputs and outputs should become an explicit
target of the reformed agricultural policy as it crucial affect adoption.
PR5: Farmer's characteristics (education, age) and environmental variables (aridity,
altitude) are also found to be important drivers of farmers' technology adoption &
diffusion and as such should be integrated in relevant policies.
PR6: Policy makers should take into account the level of farmers' risk-aversion, in
order to correctly predict the technology adoption and diffusion effects, as well as
the magnitude and direction of input responses.
Such policies are particularly relevant nowadays, given EU agricultural policy
(CAP) reform & EU Directives and almost worldwide tight government
budgets.
54
Note: Policy Recommendations
- Over 750 million olive trees are cultivated worldwide, 95% of which are in Mediterranean:
Southern Europe, North Africa and the Near East. 93% of European production from
Spain, Italy and Greece.
- Greek agriculture employs 528,000 farmers, 12% total labor force; produces 3.6% GDP
($16 billion annually).
- Greece devotes 60% of its cultivated land to olive growing; has more varieties of olives than
any other country; holds 3rd place in world olive production with more than 132 million
trees, 350,000 tons of olive oil annually, of which 82% is extra-virgin; half of annual
Greek olive oil production is exported, but only 5% of exports reflects the origin of the
bottled product. Greece exports mainly to European Union (EU), principally Italy, which
receives 3/4 of total exports.
• Greece is among the biggest beneficiaries of CAP and continues to defend a large CAP
budget. CAP reforms and especially the transition to decoupled farm payments, instability
in world agricultural commodity prices and contradicting agricultural policy signals, are
the major causes of changing farming practices. [CAP reform aims at making the
European agricultural sector more dynamic, competitive, and effective in responding to
the Europe 2020 vision of stimulating sustainable (eco & env) inclusive growth.]
• Technology diffusion efforts are strongly influenced by a piecemeal policy framework
and institutional rigidities. These need to change if Greek agriculture is to adopt a
sustainable path, especially in the light of the current financial and economic crisis. 55
CONCLUDING REMARKS
56
Concluding Remarks on Paper’s Contribution
• Our theoretical and empirical models, together with the developed
econometric approach, are general to be applied in varying
agricultural (as well as other economic sectors) setting.
• Results inform basic understanding of the ways learning processes can
be used to bring benefits to individual farmers in an agricultural
community and increase private and social welfare.
• Allows identification of peers and learning processes, identification of
the variables that influence them and identification of their respective
effects on farmers' adoption decision and profitability.
• These information can be integrated in relevant policies towards
incentivizing welfare increasing technology adoption.
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THE PAPER CAN BE DOWNLOADED :
http://www.aueb.gr/users/koundouri/resees/
COMMENTS ARE VERY WELCOMED:
[email protected]
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