The primary role of statistics is to analyze and interpret data. This is achieved by dividing the independent factors that influence the data into their component parts. However, an accurate interpretation of the data can only be made when the data is collected in such a way that facilitates the description of these independent factors.
Statistics, considered to be a distinct mathematical science rather than a branch of mathematics, is believed to have originated in 1663 with the publication of Natural and Political Observations upon the Bills of Mortality by John Graunt. Early uses of statistical methods involved the creation of policies that were based on demographic and economic data. In the 19th century, statistics was eventually recognized for its ability to collect and analyze data in general and as a result became more widely used. Today, statistics is used in almost every field of study of which includes government, business, and the natural and social sciences.
The applications of statistics can be divided into two categories: descriptive and inferential statistics. Descriptive statistics summarizes a population of data by describing what was observed in the sample of the population provided that the sample is an accurate representation of the entire group. This can be described numerically or graphically. Numeric descriptions include the mean, standard deviation, frequency, and percentage. Inferential statistics allows an experimenter to make interpretations, and predictions on the population by analyzing patterns found in the sample data.
Courses in statistics are commonly offered to students at the college level of education at most higher learning institutions. However, even some high schools around the world introduce statistics to students by the 11th or 12th grade.