Experimental Design:

Experimental  design  refers to  the framework or structure of an experiments  and as  such there are several experimental  designs. We can classify experimental design  into two broad categories viz informal experimental design and formal experimental designs.

Information Designs

When these  designs  are used  many of the effects related to the experiment can be quantified. But because of  the fairly loose way in which  they are structured the changes specifically caused by the  treatment cannot be isolated by statistical tests. The  treatments are not allocated to experimental units  randomly  but these  designs  are less expensive and easy to apply in practice.