The System of Rice Intensification and Its Puzzling Impacts on

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The System of Rice Intensification and Its
Puzzling Impacts on Household Welfare:
Evidence from Rural Indonesia
Kazushi Takahashi and Christopher B. Barrett
Presentation at workshop on
The Economics of Global Poverty
Calvin College
July 12, 2012
Motivation
“SRI is pro-poor technology”:
– Nontraditional origins (developed by missionary priest in
Madagascar, not in the labs/fields of a research institute)
– No additional or new external inputs needed
– Intensive use of labor, which the poor commonly have
Controversy within rice community
– Repeated observations of large yields gains (50-200%) on
farmers’ fields while some trials show little impact on yield
in experimental fields (McDonald et al., 2006, 2008).
– Weak theoretical foundation: Science behind SRI is
“mysterious” and is not well accepted by some crop
scientists. (“Scientific Unconfirmed Field Observations”)
Knowledge gap
What are the welfare impacts of SRI?
- Widespread adoption but in some places also much
disadoption … are users really better off?
- Experimental fields may not reflect realities faced by farmers,
while simple with-without comparisons among farmers or over
time ignore selection effects.
- Especially because of its labor use implications, must look
beyond just partial productivity of land (yield) impacts
Our core (as-yet-unanswered) question:
What are the consequence of SRI use for household
income, including off-farm income generation, and
on children’s education?
Our contribution
Use original primary data collected in rural Indonesia to:
• Identify the factors associated with SRI use
• Use those results to match on observables using propensity score
matching (PSM) (w/Rosenbaum bounds for unobservables sensitivity)
• Estimate the impacts of SRI adoption on:
– yield and rice income/HA at plot level
– Farm/off-farm/total incomes, and child school enrollment at hh level
Core findings:
- SRI indeed generates big (~64%) yield and plot-level rice income
(107%) gains but also demands more labor.
- SRI users have lower off-farm earnings, especially women’s selfemployed earnings and as a result have no significant total income gains
- SRI users’ children show no difference in school enrollment patterns
- Puzzle: where do the productivity gains go?
What is SRI?
System of Rice Intensification is a systems-based rice
production approach/technology characterized by:
1.
2.
3.
4.
young seedlings of 8-12 days old
shallow planting (1-2 cm) of one or two seedlings
sparse planting density (more than 20 × 20 cm)
intermittent irrigation (alternate wetting and drying)
It is commonly held that SRI is complex and careful/
timely water management and weed control are required.
Thus both higher yields and higher yield risk.
What is SRI?
SRI Seedling
(10 days after
Seeding)
Non-SRI
Seedlings
(30 days after
seeding)
Photos by Nippon Koei
What is SRI?
Wet
Dry
Photos by
Nippon Koei
What is SRI?
SRI
NonSRI
Photo by Christine Moser (Madagascar)
What is SRI?
Photos by Nippon Koei
Impact Evaluation
Want to know avg treatment effect on the treated (ATT):
ATT = E( y1i  y0i | Di = 1)
= E( y1i | Di = 1)  E( y0i | Di = 1)
But it is never possible to observe the outcome of SRIadopters had they not adopted SRI, ( y0i | Di = 1). So use
PSM to match conditional on probability of SRI use, as
estimable based on plot- and household-level observable
characteristics.
Vulnerable to selection-on-unobservables, so (i) try to
elicit/control for key unobservables, (ii) do sensitivity
testing using Rosenbaum bounds.
Data
Indonesia, South Sulawesi, Jeneponto District
• Poor, agriculture-dependent region
• Annual rainfall is limited (1,000 mm-1,500 mm/year)
• Irrigation project funded by JICA
• SRI promoted under the scheme since 2002
• Sample of 864 rice farmers (122 SRI adopters/742
non-adopters), operating 1202 rice plots
• Wet season, cross-sectional data collected in 2009
Descriptive Stats 1
Mean
sd
Household Characteristics
# of Cultivated Plots
Total Land Size
Adopt SRI
SRI Experience
# Agricultural Advisors
Advisors Ever Adopt SRI
(ha)
(%)
(years)
(%)
1.43
0.64
14.12
0.71
0.77
17.13
0.8
0.6
34.8
1.9
1.0
37.7
13.98
34.69
13.64
13.14
13.56
11.15
9.98
34.34
33.80
34.25
31.49
29.99
Plot Characteristics
Adopt SRI
Young Seedling
Shallow Planting
Parse Planting
Intermittent Irrigation
Full Adoption of SRI
(%)
(%)
(%)
(%)
(%)
(%)
Descriptive Stats 2
SRI
NonSRI
Diff
Plot level outcomes
Yield
(ton/ha)
5.50
2.95
2.54***
Rice income per ha
(Mill Rp)
6.67
168
2.46
1034
4.21***
N
Household level outcomes
Monthly Total Farm income
Monthly Total off-farm labor income
Monthly Off-farm wage earnings
Monthly Self-employed non-farm
income
Monthly Total labor income
N
(000
RP)
(000
RP)
(000
RP)
(000
RP)
(000
RP)
732.50
238.80 493.7***
543.90
503.90
398.10
272.30 125.80
145.90
231.60 -85.69
1276.50
742.70 533.7***
122
742
40.06
Elicited Risk Preferences
Conducted a simple/standard game in the field:
Game
A
B
EV
Difference
Risk Aversion Class
1
50000 75000 50000
12500
Inefficient
2
50000 75000 45000
10000
Risk-averse
3
50000 75000 35000
5000
Risk-averse
4
50000 75000 25000
0
Risk-averse to Risk-neutral
5
50000 75000 15000
-5000
Risk-neutral to Risk-lover
6
50000 75000 5000
-10000
Risk-lover
No change=Risk-lover
Elicited Risk Preferences
.8
1
No real risk preference differences b/n SRI users/non-users:
Risk Loving
.4
.6
Risk Neutral
0
.2
Risk Averse
1
2
3
4
# Game
SRI adopter
5
Non-Adopter
6
7
Probit SRI Use Estimates
Probit Estimates
Dummy equal to 1 if plot is in upstream
Dummy equal to 1 if plot is in midstream
Dummy equal to 1 if plot is in downstream
Dummy equal to 1 if plot recieve water directly from canal
Size of plot (ha)
Number of plots a household operates
Dummy equal to 1 if a household head is female
Number of HH members age 6 and below
Number of HH members age 15 and above
Number of HH members age between 6-14
Proportion of male household members
Number of agricultural technology advisors
Dummy equal to 1 if at least one technology advisor ever adopt SRI
Dummy equal to 1 if household is risk averse
Dummy equal to 1 if household is risk loving
Pseudo R-squared
Estimate (SE)
0.802***(0.238)
0.488** (0.199)
0.388 (0.242)
0.947*** (0.222)
0.243* (0.141)
-0.121** (0.052)
-0.823*** (0.294)
-0.330*** (0.070)
0.071** (0.032)
0.026 (0.073)
-0.432 (0.384)
0.010 (0.055)
1.843*** (0.133)
-0.425* (0.228)
-0.002 (0.269)
0.379
PSM Impact Estimates
Plot-Level Impacts of SRI Use
SRI
Yield
Seasonal rice income per ha
Family labor per ha
(ton/ha)
(Mill RP)
(mandays)
5.54
6.75
62.75
Non-SRI Difference
3.37
3.27
46.72
2.17
3.49
16.03
t-stat
Rosenbaum
bounds critical
level
6.69 ***
4.59 ***
2.56 **
Even allowing for the possibility of selection-on-unobservables,
the impacts of SRI use on rice yields, rice income per hectare and
family labor use per hectare all appear strongly positive.
3.4
2.2
1.2
PSM Impact Estimates
Household-Level Impacts of SRI Use
SRI
Non-SRI
Difference
t-stat
Rosenbaum
bounds critical
level
Monthly total farm income
(000 RP)
661.60
263.10
398.49
Monthly total off-farm labor income
of which
Off-farm wage earnings
Self-employed non-farm income
by gender
(000 RP)
571.62
976.82
-405.21
-2.20 **
1.9
(000 RP)
(000 RP)
419.05
152.57
303.04
673.78
116.01
-521.21
0.72
-5.40 ***
5.4
(000 RP)
(000 RP)
237.67
333.94
147.58
829.25
90.10
-495.30
0.89
-3.64 ***
2.8
(000 RP)
1233.21
1239.93
-6.71
Male
Female
Monthly total labor income
3.88 ***
-0.03
Note: *** p<0.01, ** p<0.05, * p<0.1
Farm income gains from SRI use are completely offset by lower
off-farm earnings, especially women’s self-employed non-farm
income. Puzzling result: no household income gains from SRI.
2.0
-
PSM Impact Estimates
Household-Level Impacts of SRI Use
The proportion of school-aged children actually go to school
of which
Male
Female
The proportion of school-aged children lagged behind
of which
Male
Female
SRI
0.92
Non-SRI
0.92
Difference
0.01
t-stat
0.16
0.99
0.88
0.12
0.95
0.89
0.11
0.04
-0.02
0.01
0.65
-0.26
0.19
0.01
0.20
0.07
0.15
-0.05
0.05
-0.79
0.62
Note: *** p<0.01, ** p<0.05, * p<0.1
Despite increased labor demands of SRI use, children in SRI using
households are no less likely to attend school or no more likely to
be delayed in school progress. Reflects offsetting income effects of
productivity gains and substitution effects on labor demand?
Conclusions
We corroborate claims of SRI’s tremendous plot level
productivity gains, but also of increased labor demand.
But we find that these productivity gains vanish at
household level. SRI seems to induce reallocation of
(women’s) time from off-farm (self-)employment, wiping
out income gains.
Some of those are perhaps invested in keeping children in
school in spite of higher returns to family labor on-farm.
Puzzle: where do the productivity gains go? Why no
disadoption?
Thank you!
Thank you for your time,
interest and insights
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