# The classical experimental designs

The purpose of the traditional experimental designs is to ascertain whether there is a causal relationship or whether an independent variable has an impact on the dependent variable. The usage of independent and dependent variables is one of the components. The former affects the dependent variable, causing it to change in a positive or negative way (Gabrenya, 2003). Testing beforehand and afterwards Before the experiment begins, the experiment’s subject is measured as part of pretesting; when the experiment is over, the subject is measured as part of posttesting.
While the control group is not, an experimental group is subjected to the experimental stimulus or conditions. Double-blind experiment refers to the situation in which the subjects and experimenters are not aware whether they are in the experimental or control group. Randomization entails assignment of random subjects to control or experimental groups.
The classical experimental design is suitable for establishing causal relationship since it allows for comparison of an experimental group and the control group. One variable (independent) is manipulated by exposing it to the experimental conditions and finding the effect it has on another (dependent).
Question 2
The classical experimental design is suitable for studying real life situations such as the impact of a certain television program on behaviors. For instance, it helps determine whether watching a film focusing on women in politics has an impact on prejudice against them. Thus, prejudice represents the dependent variable while watching the film or not represents the independent variable. The subjects under study are divided into experimental exposed to the stimulus and control groups which do not receive the stimulus (Bhattacherjee, 2012). Levels of prejudice on women are measured before and after the experiment; lastly, conclusions are made.
Question 3
Quasi-experiments are used when researchers are interested in independent variables where randomization is not possible, especially if the independent variable represents an innate characteristic such as level of happiness (Bhattacherjee, 2012). For instance, when doing an education experiment, a researcher can divide the class alphabetically or seating arrangement.
Correlation experiment establishes a relationship between two variables but does not provide proof that one variable can lead to a change in the other (Gabrenya, 2003). For instance, in a research one may ask parents to give a number of violent television programs watched by their children per week. The research can monitor the behavior of the children and establish the level of aggression depending on a number of hours they spend watching such programs in a week.

References
Bhattacherjee, A. (2012). Social science research: Principles, methods, and practices. Retrieved from
http://scholarcommons.usf.edu/cgi/viewcontent.cgi?article=1002&context=oa_textbooks
Gabrenya, W.K (2003). Research Skills for Psychology Majors: Everything you need to know to get started. Retrieved from
http://my.fit.edu/~gabrenya/IntroMethods/eBook/methods.pdf