Research

• Research design is a complete sequence of steps or procedures that need to be followed when obtaining the needed data during an investigation
• It serves as a guide during the actual experimentation
• It minimizes the cost of experimentation while maximizing the gathered information relevant to the problem
• A research design is embodied in a research proposal which is a written plan about what the researcher proposes to do in his investigation
• A research proposal contains sections like Introduction, Review of Related Literature, Methodology, and Literature Cited
• Principles of a Research Design
• Replication:

  • The experiment should be repeated several times to find an estimate of variations among observations on the group of subjects treated alike
  • Replication allows the researcher to assess the significance of the observed differences
  • Only through several repetitions of the experiment will make statistical test of significance possible
• Randomization:

  • Randomization refers to the assignment of the experiment subjects to the treatments by chance
  • It is done to create equivalent groups prior to the experiment
  • It reduces possible bias in comparative experiments
  • It also assures a valid or unbiased estimate of population parameters and the validity of the statistical test of significance
• Local Control:

  • Local control is done when balancing, grouping, and blocking of experimental units are employed in the adopted design
  • Experimental units are allocated to a block in such a manner that the units within the block are relatively homogeneous
  • Experimental units may be blocked according to certain characteristics such as height, age, weight, gender, grade level, pH level, and so on
• Control of Extraneous Variables:

  • In an experimental design, we have to make sure that no outside or extraneous variables may affect the experimental subjects
  • Identical conditions must be provided for the control and experimental groups
  • These two groups should differ only in terms of the absence (control) or presence of the treatment (experimental)
  • The principles of experimental design can be applied to single-factor, two-factor, and three-or more-factor experiments
• Types of Research Design
• There are four kinds of research designs: historical, descriptive, experimental, and case study