Agriculture Reference
In-Depth Information
between the two factors are measured with
higher precision than either of the two factors.
y
ijk
¼ μ þ γ
i
þ α
j
þ e
ij
þ β
k
þ e
0
ik
þðαβÞ
jk
þ e
00
ijk
Randomization and Layout
Like split plot design, the randomization and
allocation of the two factors in strip plot design
is done in two steps. First,
where
i ¼
1, 2,
...
,
r
;
j ¼
1, 2,
...
,
m
;
k ¼
1, 2,
...
,
n
n
horizontal factors
μ ¼
general effect
are randomly allocated to
n
horizontal strips.
γ
i
¼
additional effect due to the
i
th replication
Next the
m
levels of factor B are distributed
α
j
¼
additional effect due to the
j
th level of
among the
vertical strips independently and
randomly. The procedure of randomization is
repeated for each and every replication indepen-
dently. The ultimate layout of an
m
vertical factor A and
m
j¼
1
α
j
¼
0
β
k
¼
additional effect due to the
k
th level of
m n
strip
horizontal factor B and
P
n
j¼
plot design in
r
replication is given in
1
β
k
¼
0
(Table
10.20
):
Analysis
The analysis of strip plot design is performed in
three steps: (a) analysis of horizontal factor
effects, (b) analysis of vertical factor effects,
and (c) analysis of interaction factor effects.
Statistical Model
ðαβÞ
jk
¼
interaction effect due to the
j
th level of
factor A and the
k
th level of factor B and
P
ðαβÞ
jk
¼
P
k
ðαβÞ
jk
¼
0
r
j
e
ij
(error I)
¼
error associated with the
i
th repli-
cation and the
j
th level of vertical factor A and
2
~
e
ik
~ i.i.d.
N
(0,
σ
1
)
Table 10.20
Layout of
m n
strip plot design
1
2
:
:
:
:
:
1 …………… ….r
n-1
n
A) Whole experimental
B) Experimental area divided
in to r replications
C) Each replication divided into
m horizontal rows
1
…………………
1…
…..
………………...
1
2
:
:
:
:
n-1
n
D) Each replication divided in
m vertical columns
E) Whole experimental area n
´
m
horizontal and vertical rows
