In experiments, instead of assessing the values of the variables as they naturally occur, the researchers interfere and they are the ones who assign the values of the explanatory variable to the indiv...In experiments, instead of assessing the values of the variables as they naturally occur, the researchers interfere and they are the ones who assign the values of the explanatory variable to the individuals. The researchers “take control” of the values of the explanatory variable because they want to see how changes in the value of the explanatory variable affect the response variable. (Note: By nature, any experiment involves at least two variables.)