Research is the scientific tool to explore an idea and support it with evidence collected. Broadly there are three types of evidence namely Logical evidence, Empirical evidence, and Anecdotal evidence. Out of these, three Empirical evidence is the most practical and reliable source of the evidence. Copy the link given below and paste it in new browser window to get more information on Empirical Evidence:- http://www.transtutors.com/homework-help/economics/empirical-evidence.aspx