strengths

•  Practical - Control

  A laboratory experiment is a controlled experiment. The laboratory is an artificial environment in which the scientist can control of different variables and in order to discover what effect they have. In an experiment, an IV or independent variable (the cause) is manipulated and the DV or dependent variable (the effect) is measured; any extraneous variables are controlled.
• Practical Control (2)Through the use of an experimental group (those who are exposed to an independent variable) and a control group (those who are not exposed to the independent variable), the scientist can establish whether the independent variable impacts behaviour. Therefore, a cause and effect relationship to be established. 
• 1. Theoretical – Reliability 

  A reliable method is one that can be replicated. Positivists regard the laboratory experiment as reliable for three reasons:

  • As the original experimenter can control the conditions and specify the precise steps that were followed, others can easily repeat these steps to re-run it. Produces quantitive data so results can be compared. Detached and very objective method
• 1. Theoretical – Hypothesis testing

  Because laboratory experiments can control any variable that is of interest to the researcher, they are also an effective way to test hypotheses and predictions. If it is believed that a particular variable is the cause of a phenomenon, then an experiment can be set up where an experimental group is exposed to that variable and the control group is not, then compare the outcomes.