Question

1.identify the experimental units,response variable,factors, levels of each factor, and number of treatment of the effect of four different concerntrations of manure ( 0, 0.2, 0.4 and 0.6 cwt per acre) on the yield of three different varieties of cowpea

Answer 1

Experimental units:

In a designed experiment, the experimental units are defined as the items or individuals, on which the researchers perform the experiment.

The researchers use the varieties of oats and manure concentrations on the oats fields, to study the yield of oats.

Thus, the experimental units are field of oats.

Response variable:

In an experimental design, the response variable is defined as the variable which the researchers observe or measure, in order to assess the outcome of the experiment.

The researchers measure the yield of oats per acre, to assess how different varieties of oats and concentrations of manure per acre affect the yield.

Thus, the response variable is the yield of oats per acre.

Factor:

In a designed experiment, the factor is defined as the variable of interest. The experimenter wishes to study the effects of the factor on the response variable.

The researchers are interested to learn about the effects of variety of oat and concentration of manure per acre, on the yield of oat. This means that the variables that are of interest to the researchers are variety of oat and concentration of manure (cwt per acre).

Thus, the two factors in the experiment are variety of oats and concentration of manure (cwt per acre).

Levels:

In an experimental design, the levels are defined as different values that a factor of the experiment may take.

The factor ‘variety of oat’ takes 3 different values.

The factor ‘concentration of manure’ takes 4 different values.