J ou r n al of E con om i cs a nd R ur al D e vel op m ent vol . 1 8 N o. 1
Rural Economics
and Development
Post Harvest Grain Management Storage Techniques and Pesticides Use by Farmers
in South-West Nigeria
Okoruwa V.O.1*., O.A. Ojo1, C.M. Akintola1, A.D. Ologhobo2 and F.K. Ewete3
1
Department of Agricultural Economics University of Ibadan, Nigeria
2
D e p a r t m e n t o f A n i m a l S c i e n c e U n i v e r si t y o f I b a d a n , N i g e r i a
3
Department of Crop Protection and Environmental Biology, University of
Ibadan, Nigeria
A b s t ra c t
P o st h a r v e s t fa c i l it ie s o r a p p r o p r ia t e s t o r a g e t e c h n o lo g y h a s b e e n t h e ma jo r
p r o b le m o f N i g e r ia n a g r ic u lt u r e fo r a lo n g t i m e t h a t h a s r e s u lt e d i n c o n s i d e r a b l e
w a s t e o f a g r ic u lt u r a l o u t p u t a n d h e n c e c o n s id e r a b le lo s s t o t h e e c o no m y. T h is
s t u d y t h e r e fo r e e x a m i n e s t h e p o st h a r v e s t c h o ic e s o f g r a i n s t o r a g e t e c h n iq u e s a n d
p e s t ic id e s u s e b y f a r me r s i n s o u t h - w es t N ig e r ia . M u lt i s t a g e s a mp l i n g t e c h n i q u e
w a s u s e d t o d r a w a s a mp le o f 1 9 2 f a r me r s fr o m w h o m n e c e s s a r y i n fo r ma t io n
w h e r e e l i c it e d , w h i l e M u lt i n o m ia l lo g it mo d e l w a s u s e d i n a n a l y s i n g t h e d a t a . T h e
r e s u lt s r e v e a l e d q u a n t it y o f g r a in s t o r e d , e d u c at io n , g e n d e r o f fa r me r , c a p it a l
i n v e s t e d a n d p r ic e o f g r a i n s , a s f a c t o r s t h a t a f fe c t fa r me r s ’ c h o ic e o f s t o r a g e
t e c h n iq u e s . A l s o c h o ic e o f p e s t ic i d e u s e d b y f a r me r s w a s i n f l u e n c e d b y q u a n t it y
o f g r a i n s h a r v e s t e d , co st o f p e s t ic id e a n d c o st o f i n v e s t me n t . T h e n e e d t o ed u c a t e
f a r me r s o n t h e u s e o f p e s t ic id e s i n o r d e r t o a v o id p r o b le m s o f g r a i n c o n t a m i n a t io n
a n d a s s i s t fa r me r s ’ t o a c c e s s lo a n s a n d c r e d it fa c i l it ie s b e c o me s in e v it a b le .
K e y w o rd s : P o s t h a r v e s t , S t o r a g e t e c h n i q u e s , P e s t i c i d e s , S o u t h - we s t N i g e r i a .
*Correspondence
+2348037223832
E-mail:
v o k o ru wa @ g m a i l . c o m ;
Telephone
n u mb e r :
s u p p l y d u r in g t h e h a r v e s t i n g s e a s o n fo r
g r a d u a l r e le a s e t o t h e ma r k e t d u r i n g
o f f- s e a s o n p e r io d s . I n t h e p r o c e s s ,
s e a s o n a l p r ic e s a r e s t a b i l i z e d . P o st h a r v e s t fo o d lo s s e s a r e o n e o f t h e
i m p o r t a n t s o u r c e s o f fo o d i n s e c u r it y i n
A fr i c a . AM C O S T ( 2 0 0 6 ) e st i m a t e d p r e a n d p o st h a r v e s t fo o d c r o p lo s s a mo n g
A fr i c a n c o u n t r ie s t o b e a b o u t 1 0 % ,
w h i c h i s h i g h e r t h a n t h e g lo b a l
I n t ro d u c t i o n
S t o r a g e is p a r t ic u l a r l y i m p o r t a nt i n
a g r ic u lt u r e
because
a g r i c u lt u r a l
p r o d u ct io n is s e a s o n a l w h i l e d e m a n d s
fo r a g r ic u lt u r a l c o m mo d it ie s a r e mo r e
e v e n l y s p r e a d t h r o u g ho u t t h e ye a r . I n
t h i s c ir c u m s t a n c e , t h e r e i s n e e d t o
m e e t a v e r a g e d e ma n d b y s t o r i n g e x c e s s
53
J ou r n al of E con om i cs a nd R ur al D e vel op m ent vol . 1 8 N o. 1
a v e r a g e . N ig e r ia i s lo s i n g a b o u t 2 . 4
b i l l io n t o n n e s o f fo o d ye a r l y t o p o o r
harvest
and
storage
fa c i l it i e s
( O lu m e k o ,
1999).
Thus,
lo s s e s
a s s o c ia t e d w it h t h e s e c r o p s l i m it t h e
p o t e n t ia l i n c o me o f t h e fa r me r s ,
t h r e at e n fo o d s e c u r it y a n d e x a c e r b a t e
c o n d it io n s o f p o v e r t y a mo n g r u r a l
h o u s e h o ld s ,
w ho se
i n c o me
stream
d e p e n d s o n t h e a b i l it y t o s t o r e e x c e s s
far m
produce
fo r
a
la t e r
d at e
( Nt io k w a n a 1 9 9 9 c it e d b y T h a m a g a C h it ja e t a l . , 2 0 0 4 ) . A l l a g r i c u lt u r a l
p r o d u c e w h et h e r o f p la n t o r a n i m a l
o r ig i n , s t a r t d et e r io r at in g a l mo s t a s
s o o n a s t h e y a r e h a r v e s t e d . T h is
d e t er io r at io n ma y s t a r t w it h i n a f e w
m i n u t e s o f h a r v e s t r e s u lt i n g i n p a r t ia l
o r t o t a l lo s s w it h i n d a y s ; it ma y t a k e
p la c e v e r y s lo w l y m a k i n g t h e c r o p t o
r et a i n
s o me
q u a l it y
fo r
mo n t h s
( S et a mo u e t a l , 1 9 9 8 ) . G r a i n lo s s e s i n
m a iz e fo r e x a mp le c a n r e a c h 2 0 - 3 0 %
u n d e r r e a s o n a b le c o n d it io n s . T h i s s o r t
o f lo s s lo w e r s t h e i n c o me a n d s t a n d a r d
o f l i v i n g o f t h e fa r me r s a n d a l s o le a d s
t o w a st e o f a l a r g e fr a c t io n o f t h e
c o nt r ib u t io n t o t h e n a t io n ’ s fo o d
s u p p l y ( A s ie d u a n d V a n G a s t e l, 2 0 0 1 ;
F AO , 2 0 0 4 ) .
U d o h e t a l . , ( 2 0 0 0 ) c la s s i f i e d
storage
t e c h n iq u e s
int o
t hree
c a t e g o r ie s n a m e l y : T r a d it io n a l / lo c a l
g r a i n s s t o r a g e ( L S ) t e c h n iq u e s a t fa r m
a n d d o me s t ic l e v e l w h i c h i n c l u d e s
lo c a l c r i b s a n d r h o m b u s , p la t fo r m,
open
fie ld,
roo f
a nd
f ir e p la c e ;
I mp r o v e d / s e m i mo d e r n g r a i n s s t o r a g e
( S M S ) t e c h n iq u e s a t fa r m a n d d o me s t ic
l e v e l w h i c h a r e t h e v e n t i l a t e d c r ib s ,
i m p r o v e d r h o m b u s ; a n d B r ic k b i n s a n d
mo d e r n c e n t r a l i z e d s t o r a g e ( M S ) at
c o m me r c i a l le v e l w h i c h i n c lu d e s s i lo s
a n d w a r e h o u s e s . F a r me r s u s u a l l y m a k e
u s e o f s t o r a g e t e c h n iq u e s t h a t a r e mo s t
s u it a b le t o t h e m a n d t h e ir p o c k et at a
p o in t i n t i m e ( A s ie d u e t a l , 2 0 0 2 ) . T h e
p r o b le m s o f g r a i n s t o r a g e d i f fe r w id e l y
t h r o u g ho u t N ig e r ia a n d d e p e n d la r g e l y
o n t h e c l i m a t ic c o n d it io n s o f t h e a r e a .
T h e ma i n o b j e c t i v e s o f g r a i n s t o r a g e
a r e t o ma i n t a i n q u a l it y o f t h e p r o d u c e
fo r a lo n g p e r io d o f t i me . H o w e v e r ,
a p p r o p r ia t e h a r v e s t i n g , t r a n s p o r t at io n ,
s t o r a g e a n d ma r k e t i n g fa c i l it i e s a r e
r e q u ir e d , a s mo s t fo o d co m mo d it ie s a r e
n o t p r o c e s s e d p r o mp t l y i n t o s e co n d a r y
p r o d u ct s, d u e t o lo w le v e l o f fo o d
p r o c e s s i n g t e c h n o lo g y i n N i g e r ia . L o n g
t er m p o st - h a r v e s t p r o t e ct io n o f s t o r e d
grains aga inst
p e s t s r e ma i n s t h e
p r i m a r y c o n s t r a i n t t o ma i n t e n a n c e o f
s u f f i c i e n t fo o d s u p p l ie s i n N ig e r i a .
M o d er n
me t h o d s
of
fo o d
grain
t r e at me n t
using
i n s e c t ic id e s
a nd
fu m i g a n t s t o c h e c k p o st h a r v e s t lo s s e s
d u r i n g s t o r a g e a r e h ig h l y e x p e n s i v e
( Wh it e a n d L e e s c h , 1 9 9 5 ) . Ap a r t fr o m
b e i n g e x p e n s i v e , t h e s e t r e at me n t s d u e
t o t h e ir r e s id u a l e f f e c t s a r e t o x ic a n d
c o nt i n u o u s
a p p l ic a t io n s
of
such
che mica ls
leads
to
e n v ir o n m e n t a l
p o l lu t io n a n d h e a lt h h a z a r d s , b e s i d e s
d e v e lo p i n g r e s is t a n c e i n o r g a n is m
( S u b r a ma y a m e t a l , 1 9 9 5 ) . T h is s t u d y
t h e r e fo r e a s s e s s e s t h e c h o ic e s o f
f a r me r s i n s o u t h - w e st N ig e r ia fo r p o st
h a r v e s t g r a i n s t o r a g e t e c h n iq u e s a n d
p e s t ic id e s u s e . T h e r e s t o f t h e a r t ic le i s
o r g a n is e d a s fo l lo w s . T h e n e x t s e ct io n
d is c u s e s t h e fr a m e w o r k fo r w h ic h t h e
s t u d y w a s b a s e d , w h i l e s e c t io n t h r e e
p r e s e n t s t h e mo d e l a n d d e s c r i b e s t h e
d a t a t h i s is fo l lo w e d b y t h e r e s u lt s i n
s e c t io n fo u r a n d c o n c lu s io n i n s e c t io n
five.
54
J ou r n al of E con om i cs a nd R ur al D e vel op m ent vol . 1 8 N o. 1
a c t io n s a lo n e , w it h n o r o le fo r la r g e r
i n s t it u t io n s . C h o ic e mo d e ls e s t i ma t e d
w i l l r e f l e c t t h e a p r i o r i a s s u mp t io n s o f
t h e mo d e le r a s t o w h a t fa c t o r s a f fe c t
t h e d e c is io n p r o c e s s .
C h o ic e mo d e l s a r e d e v e lo p e d fr o m
e c o n o m ic t h e o r ie s o f r a n d o m u t i l it y. I n
e c o n o m ic s ; u t i l it y m e a n s t h e r e a l o r
f a n c i e d a b i l it y o f a g o o d o r s e r v ic e t o
s a t is f y a h u m a n w a n t . T h e c o n c e p t o f
u t i l it y a p p l i e s t o b o t h s i n g le - a t t r ib u t e
a n d mu lt i- a t t r i b u t e a lt e r n a t iv e s . T h e
fu n d a m e n t a l a s s u m p t io n
in
u t i l it y
t h eo r y i s t h a t t h e d e c is io n m a k e r s u c h
a s a fa r m e r a lw a y s c h o o s e s t h e
a lt e r n a t iv e fo r w h ic h t h e e x p e c t e d
v a lu e o f t h e u t i l it y i s ma x i m u m. I f t h a t
a s s u mp t io n i s a c c e p t e d , u t i l it y t h e o r y
c a n b e u s e d t o p r e d ic t o r p r e s c r ib e t h e
c h o ic e t h a t t h e fa r m e r w i l l m a k e , o r
s h o u ld ma k e , a mo n g t h e a v a i l a b l e
a lt e r n a t iv e s . F o r t h a t p u r p o s e, a u t i l it y
has t o be assigned to each o f t he
po ssible
(and
mu t u a l l y
e xc lusive)
a lt e r n a t iv e s . T h e p r i n c ip l e o f e x p e c t e d
u t i l it y m a x i m i z a t io n s t at e s t h at a
r at io n a l i n v e s t o r s u c h a s a fa r me r ,
w h e n fa c e d w it h a c h o ic e a mo n g a s e t
of
c o mp e t in g
fe a s i b l e
i n v e s t me n t
a lt e r n a t iv e s l i k e c h o ic e o f s t o r a g e
t e c h n iq u e s , a c t s t o s e le c t a n i n v e s t me n t
w h i c h m a x i m i z e s h i s e x p e c t e d u t i l it y
o f w e a lt h . E x p e c t e d u t i l it y t h e o r y
( E UT ) , fo r g o t t e n u n t i l V o n N e u m a n
a n d M o r g e n s t er n ( 1 9 4 4 ) , h a s b e e n t h e
b a s i s fo r mu c h d e c is io n - ma k i n g t h e o r y.
E U T a s s u me s t h a t t h e p r e fe r e n c e s o f
t h e d e c is io n m a k e r c o mp l y w it h t h e
a x io ms o f o r d er i n g , co n t i n u it y a n d
i n d e p e n d e n c e ( S t a r me r , 2 0 0 0 ) , a n d t h a t
t h e r e is a u t i l it y fu n c t io n U t h a t
a s s ig n s a n u me r ic a l v a l u e t o e a c h
a lt e r n a t iv e ( H a r d a k e r et a l . , 1 9 9 7 ) . Fo r
e x a mp l e , i f Y i s a s e t o f c h o ic e o b j e c t s
2.
T h e o re t i c a l f ra m e w o r k
R a t io n a l c h o i c e t h e o r y, a l s o k n o w n
a s c h o ic e t h e o r y o r r at io n a l a c t io n
t h eo r y i s t h e ma i n t h e o r et ic a l p a r a d ig m
i n t h e c u r r e n t l y- d o m i n a n t s c h o o l o f
m i c r o e c o no m i c s . I t is a fr a m e w o r k fo r
underst anding
and
o ft e n
fo r ma l l y
mo d e l i n g s o c i a l a n d e c o n o m i c b e h a v io r
( L a w r e n c e a n d E a s l e y, 2 0 0 8 ) . R a t io n a l
c h o ic e t h e o r y, a t t e mp t s t o d e d u c e w h a t
w i l l h a p p e n w h e n i n d i v i d u a l s a r e fa c e d
w it h a s it u a t io n s u c h a s fa r me r s c h o ic e
o f p o st h a r v e s t ma n a g e m e n t o f g r a i n s .
T h e t h e o r y b o r r o w s fr o m e c o n o m i c s t h e
a s s u mp t io n t h a t a l l i n d i v i d u a l s a r e
r a t i o n a l e g o i s t s. F a r me r s a r e a s s u m e d
t o b e r at io n a l i n t h e ir c a p a c it y t o
d e v i s e , c h o o s e , a n d p u t i n t o p r a ct ic e
e f fe c t i v e m e a n s t o c le a r e n d s ( i m p r o v e
s t a n d a r d o f l i v i n g , in c o me a n d p r o f it
m a x i m i z a t io n ) ;
t he y
are
e g o is t s
b e c a u s e t h e e n d s i n q u e s t io n g e n e r a l l y
r e fe r t o t h e s e l f- i n t e r e s t o f t h a t
i n d i v id u a l. R a t io n a l c h o ic e t h e o r y u s e s
a s p e c i f i c a n d n a r r o w d e f i n it io n o f
" r at io n a l it y " s i m p l y t o me a n t h a t a n
i n d i v id u a l s u c h a s a f a r me r a c t s t o
b a l a n c e c o s t s a g a in s t b e n e f it s t o a r r i v e
a t a ct io n t h a t ma x i m i z e s p e r s o n a l
a d v a n t a g e ( M i lt o n , 1 9 5 3 ) . Q u a l it a t i v e
c h o ic e a n a l y s i s m e t h o d s a r e u s e d t o
describe
and/o r
p r e d ic t
discret e
c h o ic e s o f d e c i s io n - ma k e r s o r t o
c la s s i f y a d i s c r e t e o u t co me a c c o r d i n g
t o a ho st o f r e g r e s so r s. F a r me r s c h o o s e
t h e a lt e r n a t iv e t h a t is l i k e l y t o g i v e
t h e m t h e g r e a t e st s at is f a c t io n i n t e r ms
o f p o st h a r v e s t t e c h n o lo g ie s ( H e a t h ,
1 9 7 6 ; C a r l i n g 1 9 9 2 ; C o le m a n , 1 9 7 3 ) .
M o d e ls t h a t r e l y o n r at io n a l c h o ic e
t h eo r y o ft e n a d o p t me t h o d o lo g ic a l
i n d i v id u a l i s m, t h e a s s u mp t io n t h a t
s o c ia l
s it u a t io n s
or
co l l e c t i v e
b e h a v io r s a r e t h e r e s u lt o f i n d i v i d u a l
55
J ou r n al of E con om i cs a nd R ur al D e vel op m ent vol . 1 8 N o. 1
( t yp e
of
storage
t e c h n iq u e s
a nd
p e s t ic id e s t o u s e ) a n d a f i n it e s u b s e t D
o f Y r e p r e s e n t s a d e c is io n p r o b le m
( i. e . t h e fa r me r s ’ b e h a v io r is d e s c r i b e d
b y a r a n d o m c h o ic e r u le ρ w h i c h
a s s ig n s t o e a c h d e c is io n p r o b le m a
p r o b a b i l it y d i s t r i b u t io n o v e r fe a s i b l e
c h o ic e s ) , t h e n t h e p r o b a b i l it y t h a t t h e
f a r me r c h o o s e s x  D is d e n o t ed
(x).
A r a n d o m u t i l it y i s a p r o b a b i l it y
m e a s u r e µ o n s o me s e t o f u t i l it y
fu n c t io n s U  { u : Y → I R } . T h e
r a n d o m c h o ic e r u le ρ m a x i m i z e s t h e
r a n d o m u t i l it y µ i f
(x) is equa l to
t h e µ ( p r o b a b i l it y o f c h o o s i n g s o me
u t i l it y f u n c t io n u t h a t at t a i n s it s
m a x i m u m i n D a t x ) . A r a n d o m u t i l it y
i s a p r o b a b i l it y m e a s u r e d e f i n e d o n a n
a p p r o p r ia t e a lg e b r a o f U . L et M ( D, u )
d e n o t e t h e ma x i m i z e r s o f u i n t h e
c h o ic e p r o b le m D ( t yp e o f s t o r a g e
t e c h n iq u e s a n d p e s t ic i d e s t o u s e ) . T h a t
is,
s t u d y i n v o l v i n g c h o ic e s a r e t h e b i n a r y
lo g it mo d e l, b i n a r y p r o b it mo d e l,
m u lt i n o m i a l
lo g it
(MNL)
mo d e l,
m u lt i n o m i a l
p r o b it
(MNP)
mo d e l,
n e s t e d lo g it mo d e l e t c .
In t hese
mo d e ls , t h e s e t o f a lt e r n a t iv e s mu s t b e
e x h a u s t i v e ( i. e . t h e s e t i n c l u d e s a l l
po ssible
a lt e r n a t iv e s ) ,
mu t u a l l y
e x c lu s i v e ( i. e . c h o o s in g o n e a lt e r n a t i v e
mea ns
not
choo sing
any
o t her
a lt e r n a t iv e s ) a n d f i n it e ( H e n s h e r e t a l .
2000).
S i n c e t h e p io n e e r i n g w o r k b y D a n i e l
McFadden in t he 1970s and 1980s
(McFadden, 1973, 1981, 1982, 1984;
H a u s ma n a n d M c F a d d e n , 1 9 8 4 ) d i s c r e t e
( mu lt i n o m ia l ) r e s p o n s e mo d e ls h a v e
b e c o me a n i m p o r t a nt t o o l o f e mp ir i c a l
r e s e a r c h e r a n d t h e s e mo d e l s h a v e b e e n
applied in ma ny areas o f eco no mic s,
i n c lu d i n g
a g r ic u lt u r a l
eco no mic s.
P r o b it mo d e l a n d lo g it mo d e l h a v e
b e e n u s e d i n e m p ir i c a l s t u d ie s t o
capture
t he
influe nce
of
s o c io e c o n o m ic
v a r ia b l e s
on
fa r m e r s ’
a d o p t io n d e c is io n s ( R a h m a n d H u f m a n ,
1 9 8 4 ; H a i l u , 1 9 9 0 ; Ke b e d e e t a l . ,
1 9 9 0 ; Ad e s i n a , 1 9 9 6 ) . I n t h e s e mo d e l s ,
f a r me r s a r e a s s u m e d t o ma k e a d o p t io n
d e c is io n s b a s e d u p o n a n o b j e c t i v e o f
u t i l it y ma x i m i z a t io n . O n t h e o t h e r
h a n d , b o t h t h e mu lt i n o m ia l lo g it a n d / o r
p r o b it a n a l y s e s h a v e b e e n e x t e n s i v e l y
u s e d in s o c ia l r e s e a r c h i n v o l v i n g mo r e
t h a n t wo d e p e n d e n t v a r ia b l e s ( T e s fa y e
e t a l . , 2 0 0 1 ; S t a t M at h C e n t e r , 2 0 0 3 ) .
I t h a s a l s o b e e n u s e d i n a g r i c u lt u r a l
p r o d u ct io n e c o n o m ic s l it e r a t u r e t o
mo d e l a c r e a g e s h a r e c h o ic e s ( e . g . ,
C a s w e l l a n d Z i l b e r ma n 1 9 8 5 ; B e w l e y
e t a l . , 1 9 8 7 ; L ic h t e n b e r g 1 9 8 9 ; Wu a n d
S e g e r so n
1995),
cro p
d e c is io n s
( L iv i n g s t o n et a l. 2 0 0 8 ) o r la n d u s e
d e c is io n s ( e . g . , L u bo w s k i e t a l . , 2 0 0 6 ) .
M(D, u) = {x  D | u · x ≥ u · y  y 
D} ……………………. (1)
W h e n a fa r me r f a c e s t h e d e c is io n
p r o b le m D a n d t h e u t i l it y fu n c t io n u is
r e a l i z e d t h e n t h e fa r me r mu s t c h o o s e
a n e l e m e n t in M ( D , u ) . Co n v e r s e l y,
w h e n t h e c h o ic e x  D is o b s e r v e d t h e n
t h e fa r m e r ’ s u t i l it y fu n c t io n m u s t b e i n
t h e s et :
N (D, x):= {u  U | u · x ≥ u · y  y 
D} ……………………..(2)
C h o ic e
mo d e ls
are
used
in
a g r ic u lt u r e
and
ot her
fie lds
to
r e p r e s e n t t h e s e le c t io n o f o n e a mo n g a
s e t o f mu t u a l l y e x c l u s i v e a lt e r n a t i v e s .
T h e a n a l yt ic a l a p p r o a c h e s t h at a r e
c o m mo n l y u s e d i n a n a d o p t io n d e c is io n
56
J ou r n al of E con om i cs a nd R ur al D e vel op m ent vol . 1 8 N o. 1
Mabo udu
et
al.,
(2000)
used
m u lt i n o m i a l lo g it a n a l y s i s mo d e l t o
assess t he co mbined e ffect o f t hree
k in d s o f v a r i a b l e s : fa r m e r s ’ s o c io e c o n o m ic
fa c t o r s ,
t e c h n o lo g y
c h a r a c t e r is t ic s a n d t h e fa r m s p e c i f i c
f a c t o r s o n t h e u s e o f fo u r t yp e s o f
i m p r o v e d c la y s t o r a g e. I n a n o t h e r
r e s e a r c h , L ia ( 1 9 9 4 ) ma d e u s e o f t h e
mo d e l t o p r e s e nt p a r a me t e r e st i m a t e s
r e p r e s e n t in g a l l c o n t r a ct s a mo n g fo u r
m a jo r c at e g o r ie s o f s t e r i l i z a t io n a mo n g
U . S . A w h it e w o me n . T h e s e mo d e ls
h a v e a ls o b e e n e mp lo ye d i n c l i m a t e
c h a n g e s t u d ie s b e c a u s e o f c o n c e p t u a l
s i m i l a r it ie s
w it h
a g r i c u lt u r a l
t e c h n o lo g y
a d o p t io n
s t u d ie s .
Fo r
e x a mp l e , N h e m a c h e n a a n d H a s s a n
(2007)
e mp lo ye d
t he
mu lt i v a r ia t e
p r o b it
mo d e l
to
a n a l yz e
facto rs
i n f l u e n c i n g t h e c h o ic e o f c l i m a t e
cha nge
a d a p t at io n
o p t io n s .
Ku r u k u la s u r i y a a n d M e n d e l s o h n ( 2 0 0 6 )
e mp lo ye d t h e m u lt i n o m i a l lo g it mo d e l
t o s e e i f c r o p c h o ic e b y f a r me r s i s
c l i m a t e s e n s it i v e . S i m i l a r l y S e o a n d
Mende lso hn
(2006)
used
t he
m u lt i n o m i a l lo g it mo d e l t o a n a l y z e
h o w l i v e s t o c k s p e c ie s c h o ic e i s c l i m a t e
s e n s it i v e . A l s o D e r e s s a e t a l . , ( 2 0 0 9 )
a d o p t e d t h e mu lt in o m i a l lo g it mo d e l t o
a n a l y z e f a c t o r s t h at a f fe c t t h e c h o ic e
o f a d a p t at io n me t h o d s i n t h e N i l e b a s i n
of
E t h io p ia .
In
t his
study
t he
m u lt i n o m i a l
lo g it
mo d e l s
were
e mp lo ye d t o e x a m i n e t h e f a c t o r s
a f fe c t i n g t h e fa r me r s ’ d e c i s io n t o u s e a
p a r t ic u la r
storage
technique
and
p e s t ic id e .
3.
M e t h o d o l o g y A n a l y t i c a l t e ch n i q u e
and data
3 . 1 . E m p i r i c a l m o d el
The
mu lt i n o m ia l
lo g it
mo d e l
( M N L ) i s i m p o r t a nt fo r a n a l yz i n g
f a r me r
a d a p t at io n
d e c i s io n s .
This
a p p r o a c h is a l s o
a p p r o p r ia t e fo r
e v a lu a t i n g a lt e r n a t iv e c o m b i n a t io n s o f
a d a p t at io n
s t r at e g ie s ,
inc lud ing
i n d i v id u a l s t r at e g ie s ( H a u s ma n a n d
W i s e , 1 9 7 8 ; Wu a n d B a b c o c k , 1 9 9 8 ) .
F u r t h e r mo r e, t h e mu lt i n o m ia l lo g it
mo d e l i s s u it a b l e fo r a lt e r n a t iv e s t h a t
can
be
u na mbiguo usly
de fined.
M u lt i n o m ia l lo g it mo d e l d e s c r i b e s t h e
b e h a v io r o f fa r me r s w h e n t h e y a r e
f a c e d w it h a v a r ie t y o f c h o ic e s w it h a
c o m mo n c o n s u mp t io n o b je c t i v e . T h e
mo d e l a s s u me s t h a t d at a ar e c a s e
spec ific ; t hat is, each independe nt
v a r ia b l e h a s a s i n g l e v a l u e fo r e a c h
case.
T h e c h o ic e o f t h e mo d e l w a s
b a s e d o n it s a b i l it y t o p er fo r m b e t t e r
w it h
d is c r e t e
c h o ic e
s t u d ie s
(McFadden, 1974 and Judge, et al,
1 9 8 5 ) . T h e mu lt i n o m ia l mo d e l w a s
u s e d t o e x p r e s s t h e p r o b a b i l it y o f a
f a r m h o u s e h o ld h e a d b e i n g i n a
p a r t ic u la r
c a t e g o r y.
The
i m p l i c it
t h eo r et ic a l
u n d e r p in n i n g
of
such
mo d e l i n g i s t h e a s s u mp t io n o f u t i l it y.
S u p p o s e a n i n d i v i d u a l f a r me r ’ s u t i l it y
a ft e r a d o p t in g a p a r t ic u l a r s t o r a g e
t e c h n o lo g y ( e . g . lo c a l s t o r ag e et c ) fo r
a g i v e n v e c t o r o f e c o n o m ic , s o c ia l, a n d
p h y s i c a l f a c t o r s ( X ) is d e n o t e d b y U i j
( X ) . T h e n , t h e p r e fe r e n c e fo r a d o p t in g
or not adopt ing can be de fined a s a
l i n e a r r e la t io n s h ip g i v e n b y:
57
J ou r n al of E con om i cs a nd R ur al D e vel op m ent vol . 1 8 N o. 1
Uij(X) = γj Xij + eij … (3)
a s s o c ia t e d w it h t h e fo u r c ho ic e s , w it h j
= 0 i f n o n e u s e o f s t o r a g e t e c h n iq u e , j
= 1 i f lo c a l s t o r a g e is u s e d , j = 2 i f
s e m i- mo d e r n s t o r a g e is u s e a n d j = 3 i f
mo d e r n s t o r a g e is u s e d . F o l lo w i n g
B a b c o c k e t a l . , ( 1 9 9 5 ) t h e p r o b a b i l it y
o f a n i n d i v i d u a l g r a i n f a r me r a d o p t in g
e it h e r o f k n o w n s t o r a g e t e c h n o lo g y ( j
which is LS =1; SMS =2; a nd MS =3),
g iv e n e c o n o m i c , s o c ia l, a n d p h y s i c a l
c h a r a c t e r is t ic s ( X ) is , P ( J | X ) a n d c a n
be spec ified by:
Or
Y i j ( X) = γ j X i j + e i j … … ( 4 )
W h e r e U i j d e n o t e t h e u t i l it y t h a t t h e
f a r me r s d e r iv e b y c h o o s in g o n e o f t h e
fo u r o u t co me s ( i. e . j i s e q u a l e it h e r o f
t h e fo l lo w i n g n o s t o r a g e ; lo c a l s t o r a g e
L S ; s e m i mo d e r n s t o r a g e S M S ; a n d
mo d e r n s t o r a g e M S ) γ j v a r ie s a n d X i j
r e ma i n s c o n s t a n t a c r o s s a lt e r n a t i v e s ;
a n d e i j is a r a n d o m e r r o r t er m
r e f l e c t i n g i n t r i n s ic a l l y r a n d o m c h o ic e
b e h a v io u r ,
me a s u r e me n t
or
s p e c i f i c a t io n e r r o r a n d u n o b s e r v e d
a t t r ib u t e s o f t h e a lt e r n a t iv e o u t co me s .
As s u m i n g t h a t t h e q u a l it a t iv e v a r ia b l e
Y i n d e x e s t h e a d o p t io n d e c is io n , t h e n it
w i l l t a k e a v a lu e o f o n e i f t h e fa r me r
a d o p t s a p a r t ic u la r t e c h n o lo g y a n d z e r o
o t h e r w is e . T h e p r o b a b i l it y t h a t a g i v e n
f a r me r w i l l u s e a lo c a l s t o r a g e
t e c h n iq u e fo r e x a m p le c a n b e e x p r e s s e d
a s a fu n c t io n o f X a s :
Pij 
1   3j 1 exp( y j X i )
Fo r j = 1, 2, 3
………….
(6)
w h e r e P i j is t h e p r o b a b i l it y o f b e i n g i n
each o f t he gro ups 1, 2 and 3
Pi 0 
1 
3
j 1
1
Fo r j = 0…… (7)
exp( y j X i )
w h e r e P i o is t h e p r o b a b i l it y o f b e i n g i n
t h e r e fe r e n c e g r o u p o r g r o u p 0 .
I n p r a ct ic e , w h e n e s t i m a t i n g t h e
mo d e l t h e c o e f f i c i e n t s o f t h e r e fe r e n c e
g r o u p ar e n o r ma l i z e d t o z er o ( M a d d a la ,
1990; Greene, 1993; Kimhi, 1994).
T h is i s b e c a u s e t h e p r o b a b i l it i e s fo r a l l
t h e c h o ic e s mu s t s u m u p t o u n it y
( G r e e n e , 1 9 9 3 ) . H e n c e , fo r 4 c h o ic e s
o n l y ( 4 - 1 ) d is t i n c t s et s o f p a r a me t e r s
c a n b e i d e n t i f i e d a n d e s t i ma t e d . T h e
n a t u r a l lo g a r it h m s o f t h e o d d r at io o f
e q u at io n s ( 6 )
and
(7)
g ive t he
e s t i ma t i n g e q u at io n ( G r e e n e , 1 9 9 3 ) a s :
P (Y  1)  P (U i1  U i 0,2,3 )
 P ( X  i1  ei1  X  i 0,2,3  ei 0,2,3 )
 P{ X ( i1   i 0,2,3 )  ei 0,2,3  ei1}
exp( y j X i )
… (5)
 P( X    )  F ( X  )
w h e r e P i s a p r o b a b i l it y fu n c t io n , ξ =
ε i o , 2 , 3 – ε i 1 is a r a n d o m d i s t u r b a n c e
t er m,  = (  i1   i 0,2,3 ) a v e c t o r o f
u n k n o w n p a r a me t e r s w h ic h c a n b e
i n t e r p r et e d a s t h e n e t i n f l u e n c e o f t h e
v e c t o r o f i n d e p e n d e n t v a r ia b l e s o n
a d o p t io n o f i n t e r c r o p p i n g , a n d F ( X  )
i s t h e c u mu l a t i v e d is t r i b u t io n fu n c t io n
fo r ξ e v a lu a t e d at X  . A ls o le t P i j ( j =
0 , 1 , 2 , 3 ) d e n o t e t h e p r o b a b i l it y
58
J ou r n al of E con om i cs a nd R ur al D e vel op m ent vol . 1 8 N o. 1
 Pij 
ln     j X i
 Pi0 
3.2. Em pirical
variables
……(8)
Marginal effects
Margina l
effect s
me a s u r e
t he
e x p e c t e d c h a n g e i n p r o b a b i l it y o f a
p a r t ic u la r c h o ic e b e i n g m a d e w it h
r e s p e ct t o a u n it c h a n g e i n a n
e x p la n a t o r y v a r i a b l e ( L o n g , 1 9 9 7 ;
G r e e n e , 2 0 0 0 ) . Ac c o r d i n g t o G r e e n e
( 1 9 9 3 ) , b y d i f f e r e n t ia t i n g e q u a t io n s ( 6 )
a n d ( 7 ) , t h e p a r t ia l d e r iv a t i v e s o r
m a r g i n a l e f f e c t s o f t h e mo d e l o n t h e
p r o b a b i l it ie s a r e :
Pj
of
T h e d e p e n d e n t v a r ia b l e i n t h e
e mp ir i c a l e s t i ma t io n fo r t h is s t u d y i s
t h e c h o ic e o f a fa r m e r u s i n g a
p a r t ic u la r s t o r a g e t e c h n iq u e s a n d / o r
p e s t ic id e s .
F o r t h e p u r p o s e s o f t h is
s t u d y, n o n - u s e o f s t o r a g e t e c h n i q u e s
a n d n o u s e o f p e s t ic i d e s w e r e t a k e n a s
t h e b a s e c a t e g o r y r e s p e c t iv e l y. T h e
c h o ic e o f e x p l a n a t o r y v a r ia b l e s i s
d ic t at e d
b y t h e o r et ic a l b e h a v io r a l
h yp o t h e s e s , e mp ir i c a l l it e r a t u r e a n d
d a t a a v a i l a b i l it y. T h e e x p la n a t o r y
v a r ia b l e s c o n s i d e r e d i n t h is s t u d y
i n c lu d e q u a n t it y o f g r a i n s h a r v e s t e d ,
p r ic e o f g r a i n s , c o st o f p e s t ic id e s ,
c a p it a l
invest ed,
gender,
ag e ,
e d u c at io n a n d fa r m i n g e x p e r ie n c e o f
t h e r e s p o n d e n t s . T a b le 1 p r o v id e s t h e
p o s s i b l e s ig n s o f t h e c o e f f ic i e n t o f
t h e s e v a r ia b l e s a s o b s e r v e d fr o m
v a r io u s st u d ie s .
Q u a n t it y
of
gra ins
har vest ed,
s t o r e d , a n d o r co n s u me d a s w e l l a s
t h e ir p r ic e a r e i m p o r t a n t i n mo d e l i n g a
d is c r e t e
c h o ic e
invo lving
storage
t e c h n iq u e s . Ac c o r d in g , B e r g a n d Ke n t
( 1 9 9 1 ) w h e n t h e r e a r e s ig n i f i c a n t i n t e r s e a s o n a l p r ic e v a r ia t io n s , fa r me r s o ft e n
s t o r e d fo r s p e c u la t i v e g a i n s . W i l l i a m e t
a l ( 1 9 9 9 ) s u g g e st e d t h at it is a d v i s a b l e
t o st o r e w h e n t h e p o st st o r ag e v a lu e
(revenue) exceeds t he tot al e xpenses
i n c u r r e d in t h e s t o r ag e p r o c e s s . S o c ia l
- e co n o m ic f a c t o r s s u c h a s t h e i n f l u e n c e
o f a g e o n c h o ic e s h a s b e e n m i x e d i n
t h e l it e r a t u r e. S o me s t u d ie s fo u n d t h a t
a g e h a d n o i n f l u e n c e o n a fa r m e r ’ s
d e c is io n t o p a r t ic ip a t e i n fo r e s t a n d
s o i l a n d w a t e r ma n a g e m e n t a c t iv it i e s
(Thacher et al., 1997; Anim, 1999;
Zha ng a nd Flick, 2001; Beke le a nd
T h is d e n o t e s t h e r e la t i v e p r o b a b i l it y o f
each o f gro ups 1, 2 and 3 to t he
p r o b a b i l it y o f t h e r e fe r e n c e g r o u p . T h e
e s t i ma t e d c o e f f i c i e n t s fo r e a c h c h o ic e
t h e r e fo r e r e f le c t t h e e f f e c t s o f X i` s o n
t h e l i k e l i h o o d o f t h e fa r me r s ’ c h o o s i n g
t h at
a lt e r n a t i v e
r e la t i v e
to
t he
r e fe r e n c e g r o u p . T h i s a p p r o a c h w a s
a ls o u s e d t o d et e r m i n e t h e c h o ic e o f
i n o r g a n ic p e s t ic i d e s ( n o u s e ; Ap r o n
p lu s a n d P h o s t o x in w it h n o u s e b e i n g
t h e r e fe r e n c e g r o u p 0 ) .
Pj
specification
 Pj [ B jk   j 1 Pj B jk ] … … … ( 9 )
W h e n t h e ma r g i n a l e f f e c t s o r p a r t ia l
d e r i v a t i v e s a r e o b t a i n e d t h e d e r i v a t io n
t e c h n iq u e s i m p l i c it l y i n d i c a t e t h a t
n e it h e r t h e s i g n n o r t h e m a g n it u d e o f
t h e ma r g in a l e f f e c t s n e e d b e a r a n y
r e la t io n s h i p
to
t h e s ig n
o f t he
c o e f f i c ie n t s u s e d i n o b t a i n i n g t h e m
(Greene, 1993).
59
J ou r n al of E con om i cs a nd R ur al D e vel op m ent vol . 1 8 N o. 1
D r a k e , 2 0 0 3 ) . Ot h e r s , h o w e v e r , fo u n d
t h at a g e is s i g n i f i c a n t l y a n d n e g a t i v e l y
r e la t e d t o fa r me r s ’ c h o i c e t o a d o p t n e w
t e c h n o lo g ie s ( G o u ld e t a l . , 1 9 8 9 ;
Feat hersto ne
and
G o o d w in ,
1993;
L a p a r a n d P a n d e l y, 1 9 9 9 ; B u r t o n e t a l . ,
1 9 9 9 ; Do l i s c a e t a l . , 2 0 0 6 ; N ya n g e n a ,
2 0 0 7 ; A n l e y e t a l . , 2 0 0 7 ) . V a r io u s
s t u d ie s h a v e s h o w n t h at g e n d e r is a n
i m p o r t a n t v a r ia b le a f f e c t i n g a d o p t io n
d e c is io n a t t h e fa r m l e v e l . F e m a l e
f a r me r s h a v e b e e n fo u n d t o b e mo r e
like ly
to
adopt
natural
resource
m a n a g e me n t a n d c o n s e r v a t io n p r a c t ic e s
( N e w ma r k e t a l . , 1 9 9 3 ; B u r t o n e t a l . ,
1 9 9 9 ; Do l i s c a e t a l . , 2 0 0 6 ; B a ya r d e t
a l . , 2 0 0 7 ) . E d u c at io n a n d fa r m i n g
e x p e r ie n c e o n t h e o t h e r h a n d a r e
i m p o r t a n t fa c t o r s in f lu e n c i n g a d o p t io n
d e c is io n s . S e v e r a l s t u d ie s h a v e s h o w n
t h at
i m p r o v in g
e d u c a t io n
a nd
d is s e m i n a t i n g
k n o w le d g e
is
an
impo rt ant
p o l ic y
me a s u r e
fo r
s t i mu l a t i n g
lo c a l
p a r t ic ip a t io n
in
v a r io u s
d e v e lo p me n t
and
nat ural
resource
ma n a g e m e n t
i n it ia t i v e s
( B u lt e n a a n d H o i b e r g , 1 9 8 3 ; A n d e r s o n
a n d T h a mp a l l a i, 1 9 9 0 ; S h i e l d s e t a l . ,
1 9 9 3 ; H e i n e n , 1 9 9 6 ; T r ao r é e t a l . ,
1 9 9 8 ; H ig m a n e t a l . , 1 9 9 9 ; A n i m,
1999;
Lapar
and
P a n d e l y,
1999;
G le n d i n n i n g e t a l . , 2 0 0 1 ; D o l i s c a e t
a l . , 2 0 0 6 ; A n l e y e t a l . , 2 0 0 7 ; T iz a l e
2 0 0 7 ) . B et t er e d u c at io n a n d mo r e
f a r m i n g e x p e r ie n c e i m p r o v e a w a r e n e s s
o f p o t e n t ia l b e n e f it s a n d w i l l i n g n e s s t o
p a r t ic ip a t e i n lo c a l n a t u r a l r e s o u r c e
m a n a g e me n t
and
co n s e r v a t io n
a c t iv it ie s .
Table 1:
Definition
of
v a ri a b l e s
u s e d i n t h e e m p i ri c a l a n a l y s i s
V a r ia b l
es
QH
PR
GD
AG E
ED
FE
CP
CI
D e f i n it io
n
Q u a n t it y
o f grains
harvest ed
P r ic e
of
grains per
kg
Gender o f
t he
respo nden
ts
Ag e
of
respo nden
ts
E d u c at io n
al
le ve l
of
respo nden
ts
Far ming
e x p e r ie n c
e
of
respo nden
ts
C o st
of
p e s t ic id e s
C a p it a l
inve st ed
Measur
e
K i lo g r a
m
Expect e
d s ig n
±
N a ir a
±
1
=
m a le
and
0
=
f e ma l e
Years
±
Years
±
Years
±
N a ir a
-
N a ir a
±
±
3.3. Data and descriptive statistics
The st udy was co nduct ed t he Sout h
w e s t er n N ig e r ia w h i c h c o n s i s t s o f
L a g o s , O g u n , O yo , O s u n , O n d o a n d
E k it i s t a t e s. T h e a r e a l i e s b e t w e e n
lo n g it u d e 2 0 3 1 1 a n d E a st 6 0 0 0 1 a n d
L a t it u d e 6 0 2 1 1 a n d 8 0 3 7 1 N ( Ag b o o la ,
1 9 7 9 ) w it h a t o t a l la n d a r e a o f 7 7 , 8 1 8
k m2 a n d a p r o je c t e d p o p u la t io n o f 2 8 ,
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767, 752 in 2002 (NPC, 2010). The
c limat e
of
S o u t h w e st
N ig e r ia
is
t r o p ic a l i n n a t u r e a n d it i s c h a r a c t e r iz e
by
wet
and
dry
seaso ns.
The
t e mp e r a t u r e r a n g e s b e t w e e n 2 1 a n d
34
while t he a nnua l ra infa ll ra nges
b e t w e e n 1 5 0 0 m m a n d 3 0 0 0 m m. T h e
v e g e t at io n i n S o u t h w e s t N ig e r ia i s
m a d e u p o f fr e s h w a t e r s w a mp a n d
m a n g r o v e fo r e st at t h e b e lt , t h e lo w
l a n d i n fo r e s t st r et c h e s i n l a n d t o O g u n
a n d p a r t o f O n d o s t at e w h i l e s e c o n d a r y
fo r e s t is t o w a r d s t h e n o r t h e r n b o u n d a r y
where derived a nd so ut hern Savanna h
e x i s t ( Ag b o o la , 1 9 7 9 ) . T h e ma i n
o c c u p at io n o f t h e p eo p le i n t h e a r e a is
far ming
w it h
s o me
petty
e n t r e p r e n e u r s h ip a n d o f f i c e w o r k s .
D a t a w e r e so u r c e d fr o m a t o t a l o f 1 9 2
g r a i n c r o p fa r me r s w h o w e r e r a n d o m l y
s a mp l e d
t hro ugh
t he
mu lt i- s t a g e
s a mp l i n g a p p r o a c h . O yo a n d O s u n
s t at e s w er e s e le c t e d o u t o f t h e f i v e
s t at e s o f s o u t h w e s t er n N ig e r ia b e c a u s e
t h e y w e r e t h e ma jo r g r a i n p r o d u c i n g
s t at e s in t h e z o n e . T wo a g r ic u lt u r a l
z o n e s e a c h w a s r a n d o m l y s e l e c t e d fr o m
t h e t wo st at e s o u t o f w h i c h s i x t e e n
v i l l a g e s ( e ig h t v i l l a g e s p e r s t at e ) w e r e
l a t e r s a mp l e d . U s in g t h e fr a m e o f
f a r me r s o b t a in e d fr o m t h e z o n a l o f f i c e s
of
t he
Ag r ic u lt u r a l
D e v e lo p me n t
P r o g r a m m e ( AD P ) o f b o t h s t at e s ,
t w e lv e f a r me r s w e r e r a n d o m l y s e le c t e d
p e r v i l l a g e a n d i n fo r ma t io n o n t yp e o f
s t o r a g e t e c h n iq u e s a n d p e s t ic id e s u s e ,
s o c io - e co n o m ic c h a r a c t er is t ic s , p r ic e s ,
t yp e a n d q u a n t it y o f g r a i n s c u lt i v a t e d
a n d s t o r e, et c w e r e o bt a i n e d fr o m t h e m
w it h s t r u ct u r e d s u r v e y i n s t r u me n t .
T h e c h a r a c t er is t ic s o f f a r me r s i n
T a b le 2 s h o w s t h at t h e r e w e r e mo r e
m a le g r a in f a r me r s t h a n f e m a le f a r me r s
i n s o u t h - w e st , N ig e r ia a n d a l a r g e
p r o p o r t io n o f t h e s e f a r me r s w e r e i n
t h e ir p r o d u ct iv e y e a r s ( 3 1 - 5 0 ye a r s ) .
A l s o , a la r g e p e r c e n t a g e ( 3 0 . 4 % ) o f t h e
f a r me r s h a d n o fo r ma l e d u c a t io n w h i l e
a la r g e p r o p o r t io n ( 7 4 . 5 % ) e n g a g e d i n
f a r m i n g a s ma jo r o c c u p at io n . T h e
s t o r a g e t e c h n iq u e s u s e d i n t h e s t u d y
a r e a in c l u d e b a s k e t s , b a g s , d r u m s ,
i m p r o v e d r h o mb u s , r a is e d p la t fo r m s ,
s i lo s a n d w a r e h o u s e s t o r a g e fa c i l it ie s .
H o w e v e r , fo l lo w i n g U d o h e t a l . ( 2 0 0 0 ) ,
t h e s t o r a g e t e c h n iq u e s w e r e c la s s i f i e d
int o
t hree
c at e g o r ie s
na me ly:
T r a d it io n a l/ lo c a l
gra ins
storage
t e c h n iq u e s ( L S ) a t fa r m a n d h o u s e h o ld
l e v e l ( t h e s e i n c lu d e - lo c a l c r i b s a n d
r h o m b u s , p la t fo r m, o p e n f i e ld , r o o f a n d
f i r e p la c e ) ; i m p r o v e d / s e m i mo d e r n
g r a i n s s t o r a g e t e c h n iq u e s ( S M S ) at
far m a nd
h o u s e h o ld
le v e l ( t h e s e
i n c lu d e - v e n t i la t e d
c r ib s ,
impro ved
r h o m b u s ) a n d b r ic k b i n s a n d mo d e r n
c e n t r a l i z e d s t o r a g e ( M S ) at co m me r c ia l
le ve l
(t hese
inc ludes i lo s
and
w a r e h o u s e s ) . I t w a s o b s e r v e d t h a t lo c a l
s t o r a g e t e c h n iq u e s w e r e mo s t l y u s e d b y
f a r me r s
(39.8%).
The
t yp e
of
p e s t ic id e s u s e d w e r e a p r o n p lu s a n d
p h o st o x i n w it h a t o t a l o f 1 3 3 fa r me r s
u s i n g p h o st o x i n . M o d e r at e l y l a r g e
p r o p o r t io n ( 4 7 . 7 % ) o f fa r me r s t h a t
u s e d lo c a l s t o r a g e t e c h n iq u e s u s e d
p h o st o x i n t o p r o t e ct t h e ir g r a i n s .
4.
Results and discussion
4.1. Determ inants of choice of grain
storage use by farmers in south-west,
Nigeria
V a r io u s
fa c t o r s
have
be ing
mo d e le d a s a f f e c t i n g t h e c h o ic e o f
s t o r a g e t e c h n i q u e s u s e d b y f a r me r s .
T h e s e f a c t o r s i n c lu d e t o t a l o f o u t p u t
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h a r v e s t e d , p r ic e o f g r a i n s , g e n d e r ,
e d u c at io n , ye a r s o f fa r m i n g e x p e r ie n c e
a n d c a p it a l i n v e s t e d . T h e e s t i ma t e d
c o e f f i c ie n t s a n d t h e c o r r e s p o n d i n g t r at io s a s w e l l a s t h e m a r g in a l i m p a c t s
o f c h a n g e s i n t h e i n d e p e n d e n t v a r ia b l e s
o n t h e p r o b a b i l it y o f fa r me r s c h o o s i n g
to use any o f t he sto rage technique are
s h o w n i n T a b le 3 . T h e l i k e l i h o o d - r at io
t e st
o f t he hypot hesis t hat
t he
c o e f f i c ie n t s o f a l l t h e e x p la n a t o r y
v a r ia b l e s a r e z e r o h a s a C h i- s q u a r e d
v a lu e o f 7 6 . 3 8 w it h 1 8 d . f. , s u g g e st i n g
t h at t h e e s t i m a t e d mo d e l i s h ig h l y
s ig n i f i c a n t a t 1 % le v e l w it h a lo g
like liho o d o f -197.628 t hus ind icat ing
a w e l l f it t e d mo d e l. T h e t a b le s h o w s
t h at t h e co e f f i c ie n t o f q u a n t it y o f
g r a i n s h a r v e s t e d ( Q H ) w a s p o s it i v e l y
s ig n i f i c a n t fo r b o t h lo c a l a n d s e m i mo d e r n
storage
t e c h n iq u e s .
The
m a r g i n a l i m p a c t s o f t h is s u g g e s t s t h a t
a 1 % i n c r e a s e i n t h e q u a n t it y o f g r a i n s
h a r v e s t e d w i l l i n c r e a s e f a r me r s o d d s
( p r o b a b i l it y) o f u s i n g lo c a l o r s e m imo d e r n s t o r a g e t e c h n iq u e s b y 0 . 0 1 % .
T h is r e s p o n s e h o w e v e r , is p e r fe c t l y
i n e la s t ic w h e n e v a l u a t e d a t t h e me a n
v a lu e s o f t h e i n d e p e n d e n t v a r ia b l e .
S i m i l a r l y,
t h e c o e f f ic i e n t
o f t he
v a r ia b l e o n ye a r s o f e d u c a t io n ( E D )
w a s p o s it i v e l y s ig n i f i c a n t fo r u s e r s o f
Age
15 – 30
31 – 50
51 – 70
71 – 90
Mean
Level
of
education
No
fo r ma l
e d u c at io n
Primar y
scho o l
Seco ndary
scho o l
P o st seco ndary
scho o l
Occupation
Far ming
Ar t is a n s
C ivil
s e r v ic e
Storage
facilities
No n- use
Local
storage
Semimo d e r n
M o d er n
Type
of
pesticides
Non use
Ap r o n p lu s
P h o st o x i n
T a b l e 2 : D i s t ri b u t i o n o f re s p o n d e n t s
a c c o rd i n g t o t h ei r s o c i o e c o n o m i c s
v a ri a b l e s
V a r ia b l e
Gender
M a le
F e ma l e
Frequenc y
165
27
Percent age
85.9
14.1
62
14
92
78
8
50.1
7.3
47.9
40.6
4.2
58
30.4
53
27.8
59
30.7
22
11.5
143
43
6
74.5
22.4
3.6
69
76
36.1
39.8
14
6.8
33
inorganic
17.3
42
17
133
21.9
8.9
69.3
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f a c t i s t h a t a n y i n c r e a s e i n c a p it a l
i n v e s t me n t ma y fo r c e fa r me r s t o
c h a n g e t h e ir s t r u ct u r e o f p r o d u ct io n
and
storage
t e c h n iq u e s
e it h e r
p o s it i v e l y o r n e g a t iv e l y. Ap a r t fr o m
t he
p o s it i v e
sig nificance
of
t he
c o e f f i c ie n t o f q u a n t it y o f h a r v e s t e d
g r a i n s , t h e co e f f i c i e n t o f p r ic e v a r ia b l e
( P R ) w a s a l s o p o s it i v e l y s ig n i f i c a n t fo r
f a r me r s u s i n g s e m i- mo d e r n s t o r a g e
f a c i l it y. T h e ma r g in a l i m p a c t is s u c h
t h at s u g g e st a 0 . 0 2 % i n c r e a s e i n t h e
o d d s o f u s i n g s e m i- mo d e r n s t o r a g e
t e c h n iq u e b y fa r m e r s fo r e v e r y 1 %
i n c r e a s e i n t h e p r ic e o f a k i lo g r a m o f
g r a i n . J u s t l ik e o t h e r s , t h e r e s p o n s e is
a ls o i n e l a s t ic a s i n d i c a t e d b y t h e
e la s t i c it y v a l u e o f 0 . 1 3 .
lo c a l a n d mo d e r n s t o r a g e t e c h n iq u e s .
T h e ma r g i n a l i m p a c t o f t h i s i n d i c a t e s
t h at a p e r c e nt a g e i n c r e a s e i n t h e ye a r s
o f fa r me r s ’ e d u c a t io n
is l i k e l y t o
i n c r e a s e t h e o d d s o f u s i n g lo c a l a n d
mo d e r n s t o r a g e t e c h n iq u e s b y a b o u t
0 . 0 3 % a n d 0 . 0 4 % r e s p e ct i v e l y b y
f a r me r s . I n t er ms o f r e s p o n s e , t h e
i n d i c a t io n a r e t h a t t h e i n c r e a s e le a d s t o
l e s s t h a n p r o p o r t io n a t e i n c r e a s e ( lo c a l,
0.02
and
mo d e r n ,
0.04)
in
t he
p r o b a b i l it y o f u s i n g lo c a l s t o r a g e a n d
mo d e r n s t o r ag e t e c h n iq u e s . T h e g e n d e r
( G D ) co e f f i c ie n t s o f t h e t h r e e s t o r a g e
t e c h n iq u e s
were
a ll
p o s it i v e l y
s ig n i f i c a n t . T h e r e w e r e ho w e v e r , so me
d i f f e r e n c e s i n t h e m a g n it u d e o f t h e
m a r g i n a l e f f e c t o f b o t h t h e lo c a l
storage
and
s e m i - mo d e r n
storage
t e c h n iq u e fr o m t h a t o f t h e mo d e r n
s t o r a g e t e c h n iq u e . Wh i l e ma r g i n a l
i m p a c t o f t h e g e n d e r v a r ia b le s u g g e s t s
a a n i n c r e a s e i n t h e o d d s o f fa r me r s
u s i n g t h e t h r e e t yp e s o f s t o r a g e
t e c h n iq u e s fr o m a p e r c e n t a g e i n c r e a s e
i n t h e n u m b e r o f fa r me r s ( e s p e c i a l l y
m a le f a r me r s ) c u lt i v a t in g g r a i n s , t h a t
o f mo d e r n t e c h n iq u e w a s mu c h h i g h e r
( 0 . 2 1 % ) w h e n c o mp a r e d w it h t h e 0 . 0 3 %
o f b o t h lo c a l a n d s e m i - mo d e r n s t o r a g e
t e c h n iq u e s . I n a l l t h e r e s p o n s e s o f
f a r me r s t o t h is c h a n g e s w a s o b s e r v e d
t o b e e la s t ic w h e n e v a l u a t e d at t h e
mea n
v a lu e s
of
t he
independe nt
v a r ia b l e . D e s p it e t h e s ig n i f i c a n c e o f
t h e e s t i ma t e d co e f f i c i e n t o f c a p it a l
i n v e s t e d v a r ia b l e ( C I ) , it s ig n i f i c a n c e
w a s h o w e v e r n e g a t iv e w it h r e s p e c t t o
t h e u s e o f lo c a l s t o r ag e t e c h n iq u e a n d
w it h a ma r g i n a l i m p a c t o f 0 . 1 0 . T h is
s u g g e s t in g a d e c r e a s e b y 0 . 1 % t h e o d d s
o f u s i n g t h e t e c h n i q u e b y fa r me r s fo r
1 % i n c r e a s e i n c a p it a l i n v e s t me n t . T h e
4.2. Determinants
of
choice
of
i n o r g a n i c p e s t i c i d e u s e b y f a rm e r s i n
south-west, Nigeria
I n t h is s e c t io n , fa c t o r s a f fe c t i n g t h e
c h o ic e o f i n o r g a n ic p e s t ic i d e s u s e d b y
f a r me r s
to
preserve
grains
were
ident ified.
Fro m
t he
p a r a me t e r
e s t i ma t e s p r e s e n t e d i n T a b l e 4 , t h e
l i k e l i h o o d - r at io t e st o f t h e h yp o t h e s is
t h at t h e c o e f f i c ie n t s o f a l l t h e
e x p la n a t o r y v a r i a b l e s a r e z e r o s h o w a
C h i- s q u a r e d v a lu e o f 2 3 1 . 7 9 w it h d . f.
1 8 , s u g g e st i n g t h a t t h e e st i m a t e d mo d e l
i s h i g h l y s i g n i f i c a n t a n d w e l l f it t e d
w it h a lo g l ik e l i h o o d o f - 3 7 . 9 . T h e
t a b le a l s o s o s h o w q u a n t it y o f g r a i n s
h a r v e s t e d ( Q H ) , co st o f p e s t ic id e ( C P )
a n d c o s t o f i n v e s t me n t ( C I ) a s t h e ma i n
v a r ia b l e s d e t e r m i n i n g t h e u s e o f
p e s t ic id e s b y f a r me r s i n t h e s t u d y a r e a .
W h e r e a s t h e c o e f f i c ie n t o f c o s t o f
p e s t ic id e w a s p o s it i v e l y s i g n i f i c a n t fo r
b o t h t h e u s e o f Ap r o n p lu s a n d
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J ou r n al of E con om i cs a nd R ur al D e vel op m ent vol . 1 8 N o. 1
P h o st o x i n p e s t ic i d e s b y f a r me r s , t h e
c o e f f i c ie n t
of
total
o ut put
was
p o s it i v e l y s i g n i f i c a n t o n l y fo r t h e u s e
of
it
P ho st o x i n
p e s t ic i d e .
The
i m p l i c a t io n s
w it h
respect
to
t he
m a r g i n a l e f f e c t is t h a t a p e r c e n t a g e
i n c r e a s e i n c o s t o f b o t h Ap r o n p lu s a n d
P h o st o x i n
p e s t ic i d e
is
like ly
to
i n c r e a s e t h e p r o b a b i l it y o f u s e o f b o t h
p e s t ic id e s b y fa r me r s b y a b o u t 0 . 0 3 %
a n d 0 . 0 4 % r e s p e ct i v e l y. T h e r e s p o n s e
o f fa r me r s t o s u c h i n c r e a s e i s h o w e v e r
i n e la s t ic . S i m i l a r l y , t h e m a r g i n a l e f f e c t
of
q u a n t it y
of
harve st ed
grains
c o e f f i c ie n t s u g g e st s a n i n c r e a s e i n t h e
p r o b a b i l it y
of
use
of
P ho sto xin
p e s t ic id e b y fa r me r s b y a b o u t 0 . 0 1 %
fo r e v e r y 1 % in c r e a s e i n t o t a l o u t w it h
t h e r e s p o n s e o f fa r me r s b e i n g i n e l a s t i c .
E st i m a t e d
c o e f f ic i e n t
of
c a p it a l
i n v e s t me n t w a s h o w e v e r , n e g a t iv e l y
s ig n i f i c a n t i n d e t e r m i n i n g t h e u s e o f
bot h
Ap r o n
p lu s
a nd
P ho sto xin
p e s t ic id e s b y fa r m e r s . T h e ma r g i n a l
e f fe c t i m p l i c a t io n is t h a t t h e r e is l i k e l y
t o b e a d e c r e a s e i n t h e p r o b a b i l it y o f
u s e o f b o t h t yp e s o f p e s t ic i d e s b y
f a r me r s b y a b o u t 0 . 0 4 % i f c a p it a l
i n v e s t me n t i n c r e a s e s b y 1 % . A ls o
f a r me r s ’ r e s p o n s e t o t h is c h a n g e i s
l i k e l y t o b e i n e l a s t ic a s s u g g e s t e d b y
t h e e la s t ic it y v a lu e .
T a b l e 3 : P a r a m e t e r e s t i m a t e s o f d e t e r mi n a n t s o f c h o i c e o f f a r m e r s s t o r a g e t e c h n i q u e s
Variable
Local Storage
QH
PR
ED
FE
GD
CI
Constant
Semi Modern Storage
QH
PR
ED
FE
GD
CI
Constant
Modern storage
QH
PR
ED
FE
GD
CI
Constant
Number of observations
Log l ikeli hood
LR chi 2( 18)
Pseudo R2
Coefficient
estimate
Standard
error
Asymptoti
c t-ratio
Elasticity
at means
Slopea
0.001***
0.114
0.141***
0.002
0.765***
-0.010***
-1.073
0.000
0.802
0.038
0.015
0.210
0.001
0.666
3.490
0.140
3.710
0.100
3.648
-4.000
-1.610
0.00
-0.02
0.02
0.00
1.12
0.00
0.01
0.03
0.03
-0.01
0.03
0.10
0.001**
2.413**
0.058
-0.013
1.912***
0.000
-19.007
0.000
1.033
0.073
0.025
0.122
0.000
1006.079
2.430
2.340
0.790
-0.530
3.074
0.180
-0.020
0.00
0.13
-0.01
-0.01
1.06
0.00
0.01
0.02
0.00
0.00
0.03
0.00
0.000
-0.142
0.100**
0.014
1.795***
-0.000
-1.326
192
-197.628
76.38***
0.162
0.000
0.992
0.046
0.018
0.01
0.000
0.763
1.530
-0.140
2.190
0.760
2.565
-0.550
-1.740
0.00
-0.06
0.04
0.02
1.38
0.00
0.000
-0.04
0.04
0.02
0.21
0.00
* * * s ig nif ic ant at 0. 0 1 %, ** si gn ifi c a nt at 0.0 5 %. * sig ni fic an t a t 0 .1 %.
a
M ar gi na l eff ect s eval u at ed at t h e s a mpl e mea ns
64
J ou r n al of E con om i cs a nd R ur al D e vel op m ent vol . 1 8 N o. 1
T a b l e 4 : P a ra m e t e r e s t i m a t e s o f d e t e rm i n a n t s o f f a r m e rs ’ c h o i c e o f u s e o f
pesticides
V a r ia b l e
C o e f f i c ie
nt
e s t i ma t e
St andard
error
As y m p t o
t ic t r at io
E la s t ic
it y a t
mea ns
S lo p e a
0.002
-1.552
0.340
-0.157
0.018
0.072**
-0.019*
-5.684
0.001
8.854
0.305
0.131
0.089
0.030
0.010
4.139
1.610
-0.180
1.110
-1.200
0.200
2.440
-1.890
-1.370
0.00
-0.03
-0.02
0.01
-0.01
0.00
0.00
0.00
-0.04
-0.02
0.00
-0.01
0.03
0.04
0.002*
-0.785
0.393
-0.170
0.044
0.066**
-0.020*
-1.339
0.001
8.720
0.298
0.113
0.067
0.030
0.010
3.304
1.690
-0.090
1.320
-1.500
0.650
2.250
-1.960
-0.410
0.00
0.02
0.06
-0.02
0.01
0.00
0.00
0.01
0.04
0.02
-0.01
0.01
0.06
0.04
Ap r o n p lu s
QH
PR
ED
AG E
FE
CP
CI
C o n s t a nt
P h o st o x i n
QH
PR
ED
AG E
FE
CP
CI
C o n s t a nt
N u m b e r o f o b s e r v a t io n s
Lo g like liho o d
L R c h i2 ( 1 8 )
192
-37.982
231.79**
*
Pseudo R2
0.753
* * * s i g n i f i ca n t a t 0 . 0 1 % , * * s i g n i f i c a n t a t 0 . 0 5 % . * s i g n i f i c a n t a t 0 . 1 % .
a
M a r g i n a l ef f e c t s e v a l u a t e d a t t h e s a mp l e m e a n s
65
J ourn al of Econ omi cs a nd Rur al De vel op ment vol. 1 8 No. 1
5.
a g r ic u lt u r e
a nd
fo o d
s e c u r it y.
T he r e fo r e t he r e is a h i g h ne e d t o
e nc o u r a g e wo me n t o p a r t ic ip a t e t o
e ns u r e
adequat e
fo o d
s u p p l y.
P r o vi s io n
of
mo d e r n
s t o r ag e
f a c i l it ie s i s h i g h ly i mp o r t a nt in t h e
s t u d y a r e a . T h is is t o r e d u c e t he
d e p e nd e nc e o f fa r me r s o n lo c a l
storage
fa c i l it ie s
w h ic h
was
d o m i na nt
in
t he
st udy
areas.
M u g h o g ho ( 1 9 8 9) , O mo r u y i e t a l . ,
( 1 9 9 5) a nd T yl e r ( 1 9 8 2) , o bs e r ve d
t ha t
p r o d u c e st o r e d
under
t he
t r a d it io na l s ys t e m u s u a l l y d o no t
k e e p lo ng a nd fa r me r s u s u a l l y s u ff e r
g r e a t lo s s e s . C a p it a l i n ve s t e d w a s
fo u nd
to
ha ve
s ig n i fi c a nt l y
i n f l u e nc e d
t he
use
of
s t o r ag e
f a c i l it ie s .
This
i mp l i e s
t ha t
G o ve r n me nt s ho u ld a s s i s t fa r me r s b y
g iv i n g t h e m a c c e s s t o lo a n s a nd
c r e d it s w h ic h w i l l i n n o s ma l l w a y
e ns u r e i n c r e a s e in p r o d u ct io n o f
g r a i ns , a d e q u a t e pr e s e r vat io n a nd
t i me l y
d i s t r ibu t io n
of
g r a i ns .
M a jo r it y o f t he fa r m e r s in t he s t u d y
a r e a w e r e o bs e r v e d t o u s e i no r g a n i c
p e s t ic id e s t o p r o t e ct ha r ve s t e d g r a i n
c ro p s bu t t he c o s t o f t he s e p e s t ic id e s
ha ve be e n fo u nd t o d e cr e a s e t he u s e .
T he r e ,
t h e r e fo r e
t he
ne e d
to
e nc o u r a g e fa r me r s t o ind u lg e i n t h e
u s e o f o r g a n ic p e s t ic id e s w h ic h i s
l e s s e xp e n s i ve a nd w it h i n t he r e a c h
o f fa r me r s . T he r e is a l s o t h e ne e d
fo r t h e p r o v is io n o f b a s i c a d u lt
e d u c a t io n fo r fa r me r s in t he a r e a i n
o r d e r t o i nc r e a s e t he ir l it e r a c y l e ve l
a nd le ve l o f u nd e r s t a nd i ng s o m e
s t o r a g e i n s t r u ct io ns a nd u s e o f
p e s t ic id e s .
Conclusio n
T he s t u d y e xa m in e d t he p o s t
h a r ve s t g r a in ma na g e me nt c ho ic e s o f
s t o r a g e a n d p e s t ic id e s u s e o f fa r me r s
i n s o ut h - w e s t N ig e r ia . F r o m t he
e mp ir i c a l f i n d i ng s , it co u ld b e
c o nc lu d e d t ha t g r a in fa r me r s in t he
s t u d y a r e a a r e mo s t ly ma l e w h i l e
mo s t o f t h e fa r m e r s w e r e i n t he ir
p ro d u ct ive ye a r s . F u r t he r mo r e , lo c a l
s t o r a g e t e c h no lo g y p r e d o mi n a t e d t h e
s t u d y a r e a a nd w a s u s e d b y g r a i n
f a r me r s . T he s t ud y e s t a b l i s h e d t ha t a
l a r g e p r o po r t io n o f t he fa r me r s h a d
n o fo r ma l e d u c a t io n w h i l e i n o r g a ni c
p e s t ic id e s i n t h e fo r m o f p ho s t o x i n
w e r e mo s t l y u s e d b y fa r me r s i n
s o ut h- w e st ,
N ig e r ia
to
pr o t e ct
h a r ve s t e d g r a i ns . F a c t o r s w h ic h
s ig n i f i c a nt l y i n f l u e nc in g fa r me r s ’
c ho ic e o f s t o r a g e t e c hn iq u e s a nd
p e s t ic id e s u s e d i n c lu d e d q u a nt it y o f
g r a i n s ha r ve s t e d , co s t o f p e s t ic id e
a nd c o s t o f i n ve s t me nt , pr ic e o f
g r a i n s , g e nd e r o f fa r me r s , e d u c a t io n,
c a p it a l
i n ve s t e d
a nd
c o st
of
p e s t ic id e s .
Fro m
h i s t o r y,
past
g o ve r n me nt p o l ic y s e e ms t o ha ve
c o nc e nt r a t e d mo r e o n a s p e c t s o f
p ro d u ct io n a nd ma r k e t in g p r o p er a nd
l e s s o n w ha t ha p p e ns i n b e t w e e n
t he s e t wo pr o c e s s e s . T he ne e d t o
s t o r e a nd p r e s e r ve fo o d w h ic h ha s
b e e n h a r ve s t e d i s t he r e fo r e a s
i m p o r t a nt a s it s p r o d u ct io n. T h e
fo l lo w i n g
are
d e s ir a b l e
a c t io n s
r e c o mm e nd e d t o e n s u r e a p e r fe c t
p r e s e r va t io n a nd s u p p l y o f g o o d
q u a l it y g r a i ns a l l ye a r r o u n d , w it h
t he u s e o f a d e q u a t e a nd a p p r o pr ia t e
s t o r a g e t e c hn iq u e s a nd e f fi c ie nt u s e
of
p e s t ic i d e s .
T he r e
is
ne e d
t he r e fo r e,
to
inc r e a s e
t he
p a r t ic ip a t io n o f w o me n i n g r a i n
p ro d u ct io n
in
t he
stu dy
area.
V a r io u s s t u d ie s ha v e s ho w n t ha t
w o me n p l a y a ve r y im p o r t a nt r o le i n
66
J ourn al of Econ omi cs a nd Rur al De vel op ment vol. 1 8 No. 1
P ro c e e d in g .
I I T A - Co t o no u .
Be n i n.
A s i e d u , E . A , P . Ad u s e i- A k o w u a h,
A. G . J . V a n G a s t e l a nd P . Y . K .
S a l l a h,
( 2 0 0 2) :
E f fe c t
of
d e hu m i d i f i e r s
d r yi ng
on
the
s t o r a g e l i f e o f ma i z e . Cr o p R e s .
I n s t . , 4 2 : 1 96 - 1 99 .
B a bc o c k , B. A; Cha he r l i, N . M . a n d
L a k s h m i n a r ia ya m, P . G . ( 1 99 5 ) :
“P r o gr a mm e
P a r t ic ip a t io n
a nd
F a r m- Le ve l.
Ad o pt io n
of
Co n s e r va t io n T i l l a g e : E s t i ma t e s
fr o m a M u lt ino mi a l L o g it M o d e l”
Wo r k i ng
paper
9 5 - WP
136,
Ce nt r e fo r A g r ic u lt u r a l a n d R u r a l
D e ve lo p me nt ,
Iowa
State
U n i ve r s it y, A me s , Io w a.
B a ya r d , B . J o l l y, C . M . a nd S ha n n o n,
D . A . ( 2 0 0 7) : T he e co no m ic s o f
a d o pt io n a nd ma n a g e m e nt o f a l le y
c r o p p i ng i n H a it i. J o u r na l o f
E n v ir o n me nt a l M a n a g e me nt 8 4 ,
6 2 – 7 0.
B e k e le , W a nd D r a k e , L . ( 2 00 3 ) :
So il
and
wat er
c o ns e r v a t io n
d e c is io n be h a v io r o f s u bs is t e nc e
fa r me r s i n t he E a s t er n H ig h l a nd s
o f E t h io p ia : a c a s e s t u d y o f t h e
H u n d e - La ft o
ar e a . e co lo g ic a l
E c o no m ic s 4 6 , 4 3 7 –5 1 .
B e r g , E . a nd L . K e nt ( 1 99 1 ) : T he
e c o n o mic s o f c e r e a l ba nk s i n t h e
S a he l.
C o ns u lt a nc y
Report
prepared
fo r
U S AI D
by
D e ve lo p me nt A lt e r na t iv e s I nc . ,
Be t h s e d a , M ar yl a nd .
B e w le y, R . , Y o u ng , T . , Co l ma n, D .
( 1 9 8 7) : A s y s t e m a p p r o a c h t o
mo d e ll i ng s u p p l y e q u a t io n s i n
a g r ic u lt u r e .
J o ur na l
of
Ag r ic u lt u r a l E c o no mic s , 3 8 ( 2 ) :
1 5 1 - 1 66 .
B u lt e na , G . L . a nd H o i be r g , E . O
( 1 9 8 3) : F a ct o r s a f fe c t i ng fa r me r s ’
a d o pt io n
of
c o ns e r v a t io n
t i l l a g e . jo u r n a l o f S o i l a n d Wa t e r
Co n s e r va t io n 3 8 , 2 8 1 –8 4 .
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An a l ys i s
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a d o pt io n
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K l e m me ,
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fa r m a nd o p e r at o r c h a r a ct e r is t ic s
a nd
t he
p e r c e p t io n
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so il
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G r e e ne , WH , 2 0 0 0 . E co no me t r ic
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a bo u t t h e i mp a c t o f h o u s e ho ld
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s ys t e ms
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H a u s ma n, J a nd Wis e , D . ( 1 9 7 8) : A
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c ho ic e :
D is c r e t e
d e c is io n s
r e c o g n iz i n g
i nt e r d e p e n d e nc e
a nd
he t e r o g e neo u s
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E c o no me t r ic a 4 6 , 4 03 – 2 6.
H e a t h A. ( 1 9 7 6) : R a t i o n a l C h oi c e
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H e i ne n ,
J.T.
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H u ma n
be ha v io r ,
in c e nt i ve s
a nd
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areas
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J ourn al of Econ omi cs a nd Rur al De vel op ment vol. 1 8 No. 1
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M i me o ,
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J u d g e G . G . , H i l l R. C . , G r if f it h s
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e c o n o m e t r i c s . J o hn W i le y a nd
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K e be d e , Y . , K. G u n ja l a nd G . C o ff i n
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ne w
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in
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Ag r ic . E co n ., 4: 2 7 - 43 .
K i mh i, A . ( 1 9 9 4 ) : “P a r t ic ip a t io n o f
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o f F u l l- T im e O f f- F a r m Wo r k ”
Jo urnal
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CEEPA
D is c u s s io n P a p e r N o . 2 6. C e nt r e
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E co no m ic s 2 1 , 2 4 1 –5 6 .
L a w r e nc e E . Blu me a nd D a v i d
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I nt er pr et i ng
P r o ba b i l it y M o d e l s . L o g it , P r o b it
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Linear
M o d e ls . Q u a nt it a t iv e A p p l i c a t io n
in
t he
S o c ia l
Science
I nt e r n at io na l.
E d u c at io n
a nd
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L a nd
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N o r t he r n h ig h p l a i n s . A me r i c a n
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L i v i ng s t o n, M . , Ro be rt s , M . J. , Ru st ,
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me e t i n g , O r la nd o , F lo r id a , 2 7 - 2 9
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J.S.
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Re g r e s s io n
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fo r
c a t e go r ic a l
a nd
l i m it e d
d e p e nd e nt
va r ia b l e s :
Ad v a nc e d q u a nt it a t iv e t e c h n iq u e s
i n t he s o c ia l s c i e nc e . S e r ie s 7 .
S a g e , T ho u s a n d O a k s , Ca l ifo r n i a .
L u bo w s k i, R. N . , P la n t i ng a , A . J . ,
S t a v i ns , R. N . ( 2 0 0 6 ) : L a nd - u s e
a nd c a r b o n s i nk s :
E co n o me t r ic
e s t i ma t io n
of
the
c a r bo n
s e q u e s t r at io n
su pp ly
fu nc t io n. Jo ur na l o f
E nv ir o n me nt a l
E c o no mi c s
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M a bo u do u , A . G . , P . Y. A d e g b o la ,
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A mo u z o u,
( 2 0 0 0) :
Fact ors
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fo r ma iz e i n Ce nt r a l a n d N o r t he r n
Be n i n, b io lo g ic a l C o nt r o l C e nt e r
fo r A fr ic a , I nt e r nat io na l I n s t it u t e
o f T ro p ic a l A g r ic u lt u r e ( II T A) ,
0 8 B P 0 9 32 , Co t o no u, Be n in.
M a d d a la , G . S . ( 1 9 90 ) : L im it e d
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V a r ia b l e s i n E co no me t r ic s .
C a mb r id g e
U n iv e r s it y
Pr ess,
Ca mbr id g e .
M c F a d d e n , D . ( 1 9 73 ) : “ C o nd it io na l
L o g it An a l ys i s o f Q u a l it a t i v e
Ch o ic e B e ha v io r ” i n P . Z a r e mbk a
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M c fa d d e n D . ( 1 9 7 4 ): Co nd it io na l
L o g it A na l ys i s o f Q u a l it a t i ve
C ho ic e B e ha v io u r . I n: Z a r e mb k a
P.,
(E d s . ),
F r o nt ie r s
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M c F a d d e n, D . ( 1 9 8 1 ) : “E co n o me t r ic
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S t r u c t u r a l A n a l y s i s of D i s c r e t e
Da ta
wi t h
Econ ometric
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MIT
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M c F a d d e n, D . , ( 1 9 8 2) : “Q u a l it a t iv e
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I nvited Papers fo r the Fou rth
World
Congress
of
th e
Econometric
Society,
1-37,
C a mbr id g e
U n iv e r s it y
Pr ess,
C a mbr id g e , U K.
M c F a d d e n, D . ( 1 9 8 4 ) : “E co n o me t r ic
A n a l ys i s o f Q u a l it a t iv e R e s p o ns e
M o d e ls , ” i n G r i l i c he s a nd
I nt r il i g a t o r
(eds),
Handbook
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Vo l.
2,
13 9 5 1 4 5 7 , A ms t e r d a m, No rt h H o l la nd .
M i lt o n F r ie d ma n ( 1 9 5 3 ) : E s s a y s i n
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M u g ho g ho M . J . K ( 1 9 8 9) : M a la w i :
Foo d
s e c u r it y
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Rukuni
(Ed):
Food
Secu rity
Policies in the SADC Region.
H a r a r e . U n i ve r s it y o f Z i m b a bw e
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Foo d
S e c ur it y
Research
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S o ut he r n
A fr ic a
P r o je c t .
D e p a r t me nt
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Ag r ic u lt u r a l
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N e w ma r k ,
W. D . ,
Le o na r d ,
N.L,
S a r ik o , H . I . a nd G a ma s s a , D . M .
( 1 9 9 3) : Co ns e r v a t io n a t t it u d e s o f
lo c a l p e o p le l i v i n g a d ja c e nt t o
f iv e p r o t e c t e d a r e a s in T a nz a n i a .
B io lo g ic a l C o ns e r va t io n 6 3 ( 2 ) ,
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N he m a c he na , C. a n d H a s s a n , R .
( 2 0 0 7) : M i c r o- L e v e l A na l y s i s of
F a r m e r s ’ A d a p t at i o n t o Cl i m a t e
Ch a n g e i n S ou t h e r n A f r i c a . I F P R I
D is c u s s io n P a p e r No . 0 0 7 1 4 .
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Foo d
P o l ic y
Re s e a r c h I ns t it u t e. Wa s h in g t o n
DC.
N P C ( 2 0 1 0) : N at io na l P o p u la t io n
Co m mi s s io n: S t at e po p u la t io n i n
N ig e r ia , A bu j a , N ig e r ia .
h t t p : / / ww w. p o p u l a t i o n. g o v. n g / i n d e x.
p h p ? o p ti o n . . .
N ya ng e na ,
W.
( 2 0 0 7) :
S o c ia l
d e t er mi na nt s o f s o i l a nd w a t e r
c o ns e r va t io n i n r u r a l K e n y a .
Environment,
Development
Sustainability.
and
O lu me k o , D . O . ( 1 9 9 9 ) : S i m u la t io n
a nd P e r fo r ma nc e E v a lu a t io n o f
M e t a l a nd B r ic k O n - fa r m G r a i n
S t o r a g e S t r u c t ur e in S o u t h w e s t e r n
N ig e r ia . U np u b l i s he d P hD T he s i s
S u b mit t e d t o t he D e p a r t me nt o f
Ag r ic u lt u r a l
E ng in e e r i ng ,
U n i ve r s it y o f I ba d a n, N ig e r ia .
O mo r u yi S . A, O r h u e U . X , Ak e - o b o
A. A ,
Ak h i mi e n
C. I .
( 1 99 5 ) :
Prescrib ed agricultural science
fo r sen ior seco ndary schoo ls,
Be n i n
C it y:
Idodo
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E c o n. As s o c ia t io n, 4 0 5 - 4 1 3.
S e o , N . a nd M e nd e l s o h n, R . ( 2 0 0 6 ) :
Cl i m a t e c h a n g e ad a p t at i o n i n
A f r i c a: a m i c r o e c o n o m i c a na l y s i s
of
livestock
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CEEPA
D is c u s s io n P a p e r N o . 1 9. C e nt r e
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S e t a mo h, M , K. F . C a r d w e l l, F .
S c u lt he s s a nd K . H e l l ( 1 9 9 8 ) :
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e a r s in Re p u b l i c o f B e n in . J . E c o n
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S h ie l d s , M . L , Ra yu n i ya r , G . P a nd
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A
lo ng it u d i na l a na l ys i s o f fa c t o r s
i n f lu e nc i n g i nc r e a s e d t e c hn o lo g y
a d o p t io n i n S w a z il a nd , 1 9 8 5 –
1 9 9 1 . T h e J o ur na l o f D e v e lo p i ng
a r e a s 2 7, 4 6 9 – 84 .
S t a r me r , C. , 2 0 0 0. D e ve lo p me nt s i n
no n- e x p e c t e d ut i l it y t he o r y: t he
hu nt fo r a d e s c r ip t i ve t he o r y o f
c ho ic e u nd e r r is k , J o u r na l o f
E co no m ic L it e r a t u r e 3 8, 3 3 2 - 3 8 2.
St at
Mat h
C e nt e r
( 2 00 3 ) :
M u lt i no mia l lo g it r e g r e s s io n a
c a t e go r ic a l
a na l ys i s .
I nd ia na
U n iv e r s it y.
URL/s t a t ma t h/ s t at / a l l/ c a t / 2 c l. ht m l.
S u br a ma n y a m,
B.,
and
D . W.
Hagstr um
(1995):
R e s is t a nc e
me a s u r e me nt a nd ma na g e me nt . I n:
I nt e gr at e d ma n a g e m e nt o f in s e c t s
in
s t o r ed
pr o d u c t s .
Marcel
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T e s fa ye , Z . , T . B e d a s s a a nd T .
S h ie f e r a w ( 2 0 0 1) : D et e r mi na nt o f
a d o p t io n
of
im p r o ve d
ma iz e
t e c hn o lo g ie s
in
ma jo r
ma iz e
g r o w i ng r e g io ns o f E t h io p ia .
P a p e r p r e s e nt e d at t he s e c o nd
N a t io n a l M a i z e Wo r k s ho p o f
E t h io p ia .
T ha c he r , T . , L e e D . R a nd S c he l h a s ,
J . W. ( 1 9 9 7 ) : F a r me r p a r t ic ip a t io n
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r e fo r e st at io n
i nc e nt i ve
p r o gr a ms
in
Co st a
R ic a .
Ag r o fo r e s t r y S ys t e ms 3 5 ( 3 ) ,
2 6 9 – 8 9.
T ha ma g a - C h it i j a , J . M . , H e nd r ik s ,
S . L ., O r t ma na , G . F . , a nd G r e e n,
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S t o r a g e o n r u r a l h o u s e ho ld fo o d
s e c u r it y i n no r t he r n Kw a z u lu Natal Tydskrif vir Gesin sekologie
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Fro m
ht t p : / / w w w . u p. a c . z a / a c a d e mi c / a c a
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T iz a l e , C . Y . ( 2 00 7 ) : T he d yn a mi c s
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fo r o pt i ma l m a na g e me nt i n t h e
Ce nt r a l H i g h la nd s o f E t h io p ia .
P hD
t he s is ,
D e p a r t me nt
of
Ag r ic u lt u r a l
E c o no mi c s ,
E x t e ns io n
a nd
Rural
D e ve lo p me nt , F a c u lt y o f N a t u r a l
a nd
A g r ic u lt u r a l
S c ie nc e s ,
U n i ve r s it y o f P r et o r ia .
T r ao r é , N. , L a nd r y, R a nd A ma r a , N .
( 1 9 9 8) : O n - fa r m a d o pt io n o f
c o ns e r va t io n p r a ct ic e s : T he r o le
of
fa r m
a nd
fa r me r
c ha r a c t e r is t ic s , p e r c e p t io ns , a nd
he a lt h ha z a r d s . L a nd E c o no mic s
7 4 , 1 14 – 2 7.
T yl e r P . S . ( 1 9 8 2) : M is c o nc e p t io n o f
fo o d lo s s e s F o o d a n d N ut r i t i o n
B u l l e t i n 4( 2 ) , T he U n it e d N a t io ns
U n i ve r s it y
Pr ess,
fr o m
< ht t p : / / w w w . u nu . e d u /
u nu p r e s s / fo o d / 8 F 0 4 2 e / 8 F 0 4 2 E 05 .
ht m>
( R e t r ie ve d
Au g u s t
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2006).
U d o h J . M . , K . F . C a r d w e l l a nd T .
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5 a g r o e c o lo g ic a l Z o ne s o f
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W h it e , N . D. G . a n d J . G . L e e s c h
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I n t e g r a t e d M a na g e m e n t of I n s e c t s
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S u br a ma n ya m, D . W. H a g s t r u m.
Marcel
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New
York,
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W i l l i a m, T . T . , L . W. M ar k a n d H . A .
S t e p he n , ( 1 9 9 9) : S e a s o na l it y a nd
it s e f fe c t s o n c r o p ma r k e t s. T e xa s
Ag r ic u lt u r a l E xt e ns io n S e r v ic e ,
T h e T e xa s A a nd M U n iv e r s it y
S ys t e m. 1 . 5 M , N e w E C O . L - 5 3 0 6
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Wu , J . a nd B a bc o c k B. A . ( 1 99 8 ) :
T he c ho ic e o f t i l l a g e , r o t at io n,
a nd
so il
t e s t ing
p r a c t ic e s :
E co no m ic
a nd
e n v ir o n me nt a l
i mp l i c a t io ns .
A me r ic a n J o u r na l o f Ag r ic u lt u r a l
E co no m ic s 8 0 , 4 9 4 –5 1 1 .
Wu , J . a n d S e g er so n , K . ( 1 9 9 5 ) : T h e
i mp a c t o f p o l ic i e s a nd la nd
c ha r a c t e r is t ic s
on
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g r o u nd w at e r
p o l lu t io n
in
W i s c o n s i n. A m e r ic a n J o u r na l o f
Ag r ic u lt u r a l E c o no mic s , 7 7 ( 4 ) :
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Z ha ng , D a nd F l i c k , W. ( 2 0 0 1 ) :
S t ic k s , c a r ro t s , a nd r e fo r e s t at io n
i n ve s t me nt .
La nd
E c o no mic s
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72