Incomplete block design, experimental

These experimental designs are known as balanced incomplete blocks. They are balanced because each treatment occurs to exactly the same extent they are incomplete because no block contains the full number of treatments. They suffer from the restriction that balanced arrangements are not possible for all experimental set-ups. Broadly speaking, if we fix the number of treatments that we wish to compare, and if the number of experiments per batch (or block ) is also fixed, then the number of replication of each treatment is thereby determined. This is the principal disadvantage of these designs the number of replications they require may be greater than we think are necessary to attain sufficient accuracy. 

A general description of the experimental design known as balanced incomplete blocks have been given in Chapter I Section (f), and will not be repeated here. This chapter will give the methods of computation for such experiments, the method and notation being based on Yates( ). 

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