What is Statistics?

Statistics is the science and practice of developing human knowledge through the use of empirical data expressed in quantitative form. It is based on statistical theory which is a branch of applied mathematics. Within statistical theory, randomness and uncertainty are modelled by probability theory. Because one aim of statistics is to produce the "best" information from available data, some authors consider statistics a branch of decision theory. Statistical practice includes the planning, summarizing, and interpreting …

…just be a coincidence. In this diagram, Nightingale resolved the problem of the "bat's wing" by using areas to represent the variation in the death rate, instead of the length of radial lines. The blue wedges, representing death by sickness, are far bigger than those representing wounds. The message of this graphic is twofold: first, most of the fatalities during the war were from sickness and second, improvements in hygiene dramatically reduced the death rate.