Introduction The …eld of statistics is concerned with the scienti…c study of collecting, or- ganizing, analyzing, and drawing conclusions from data. Statistical methods help us to transform data to knowledge. Statistical concepts enable us to solve problems in a diversity of contexts, add substance to decisions, and re- duce guesswork. The discipline of statistics stemmed from the need to place knowledge management on a systematic evidence base. Earlier works on sta- tistics dealt only with the collection, organization, and presentation of data in the form of tables and charts. In order to place statistical knowledge on a systematic evidence base, we require a study of the laws of probability. In mathematical statistics we create a probabilistic model and view the data as a set of random outcomes from that model. Advances probability theory enable us to draw valid conclusions and to make reasonable decisions on the basis of data.