Statistics is the mathematical science involved in the application of quantitative principles to the collection, analysis, and presentation of numerical data. The practice of statistics utilizes data from some population in order to describe it meaningfully, to draw conclusions from it, and make informed decisions. The population may be a community, an organization, a production line, a service counter, or a phenomenon such as the weather. Statisticians determine which quantitative model is correct for a given type of problem and they decide what kinds of data should be collected and examined. Applied statistics concerns the application of the general methodology to particular problems. This often calls for use of the techniques of computer-based data analysis. Some examples of statistical problems are:
Interpretation of evidence linking environmental factors and disease,
Design of experiments to evaluate effectiveness of pharmaceuticals,
Mining data to discover target segments in the population,
Market research to estimate demand for a new product,
Opinion polling in politics,
Estimation of the size of an animal population to aid in establishing regulations for conservation,
Reliability studies for determining warranties,
Improving the quality of a service or manufactured item,
Weather forecasting,
Analysis of errors in scientific experiments, and
Prediction of stock market prices.
Statisticians are key contributors to scientific methodologies. They use their quantitative knowledge to the design data collection schemes, process the data, analyze the data, and interpret the results. Further, statisticians often make critical evaluations on the reliability of data and whether inferences drawn from can be made confidently. They also help to identify misleading abuses of data that may be portraying an inaccurate account of a situation.
Theoretical statistics concerns general classes of problems and the