1) Differentiate between the Laboratory and Field Experiments
The difference between Laboratory experiment and the field experiment is simple. Usually the laboratory experiment is conducted in an artificial situation. Where as the field experiment is carried out in a real-life setting.

2) Enumerate the different experimental designs.
Before – After or Pre test experimental design
After only or Post-test only experimental design
Quasi – Design or Post-facto experimental design; and
Special design or Mixed design

3) State the advantages of experimental method.

  • Its power to determine casual relationship is much better that that of all other methods
  • The influence of extraneous variable can be more effectively controlled
  • The element of human error is more reduced
  • More conditions may be created and tested in this method
  • This method yields generally exact measurement and it can be repeated.


Variable : The treatment variable
Null Hypothesis : Hypothesis, that there is no evidence that the treatment has an effect
Experimental Hypothesis : A prediction that the treatment will cause an effect
Randomisation : A tool used to establish internal variability
Mixed Design : A special design where one factor is between and the other is within.

Source:IGNOU Study Material