# Research Design

**Topics:**Randomness, Randomization, Experimental design

**Pages:**1 (342 words)

**Published:**February 25, 2013

TWO GROUP SIMPLE RANDOMIZED DESIGN: This is a form of completely randomized design (C.R. design). In a two-group simple randomized design, first of all the population is defined and then from the population a sample is selected randomly. Further, requirements of this design is that items, after being selected randomly from the population, be randomly assigned to the experimental and control groups (such random assignment of items to two groups is technically described as principle of randomization). Thus, this design yields two groups as the representatives of the population. In a diagram form, this design can be shown in this way:

Since in the sample randomized design, the elements constituting the sample are randomly drawn from the same population and randomly assigned to the experimental and control groups, it becomes possible to draw conclusions on the basis of samples applicable for the population. The two groups (experimental and control groups) of such a design are given different treatments of the independent variables. This design of experiment is quite common in research studies concerning behavioural sciences. The merit of such a design is that it is simple and randomizes the differences among the sample items. The disadvantage is that the individual differences among those conducting the treatments are not eliminated, i.e., it does not control the extraneous variable and as such the result of the experiment may not depict a correct picture. This can be illustrated by taking an example. Suppose a researcher wants to compare two groups of students who have been randomly selected and randomly assigned. Two different treatments namely; the usual training and the specialized training are being given to the two groups. The researcher hypothesises greater gains for the group receiving specialized training. To determine this, he tests each group before and after...

Please join StudyMode to read the full document