Recording sheets should meet the following require-
ments:
 a. Field data should be usable directly for
 processing; eliminating transcriptions saves
 time, cuts the costs of trials,and eliminates
 one source of error.
 b. There should always be at least one
 original and one copy of records.
 c. Records should be easy to read; this
 implies not too many records per sheet.
 d. Sheet size should be such that it can easily
 be handled in the field, as well as filed in
 standard files.

Processing

 Before data are analyzed, they must be inspected for
irregularities, processed,and standardized.

Unusual values

 Before any data analysis is attempted, the patterns
of variation in the data should be studied. Attention
should be given to numbers which appear to be unusual
(called outliers), and those which are missing (called
missing plots). An attempt should also be made to see if
the variation is homogeneous throughout the data set. The
range is a useful device for this. An example of the use
of the range, to look for non-homogeneity of variation, is
illustrated with field data from a trial with six
treatments and three replications:

 BLOCK I BLOCK II BLOCK III
 Treatment 1 40 60 80
 Treatment 2 30 55 120
 Treatment 3 20 70 92
 Treatment 4 20 42 60
 Treatment 5 40 58 80
 Treatment 6 50 68 92

The range in yield for each of the treatments is obtained
by finding the difference between the highest and lowest
values in each treatment: