Example: pn (+) = p(-) x n (-)


pnv (-) = p (-) x nv (+)


TABLE 111-3.


Example of a 23 trial on maize with
plant density (P), nitrogen (N), and
variety (V).


Treatments Treat- Treat-
 Code Block I Block II ment ment
 totals means

 kg/plot

P N V (1)* 4.3 3.9 8.2 4.1
o 0 0
P1 N V p 4.5 5.9 10.4 5.2
1 o o
P N V n 4.5 5.4 9.9 4.95

P N V, v 5.7 6.6 12.3 6.15

P1 Nl Vo pn 6.4 6.7 13.1 6.55

P1 N V1 pv 6.9 7.1 14.0 7.0

P N1 V1 nv 6.4 7.0 13.4 6.7

P1 Nl V1 pnv 8.6 8.8 17.4 8.7


Totals 47.3 51.4 98.7

Source: Adapted from CIMMYT data.


*(1) is the local or traditional
level combination.


treatment or the lowest


 Table III-4 has the following characteristics: 1)
every row has an equal number of plus and minus signs,
except for row M; and 2) the sum of products of signs in
any given pair of rows is zero (Montgomery, 1976). For
another reference on the signs for these contrast
coefficients see Cochran and Cox (1957, p 157).

Step 2. The total factorial effects are calculated by the
algebraic addition of the yields of the same treatment
using the corresponding plus (+) or minus (-) sign of each
component, and the result is written in the space for the