statistik

Statistik, or statistics, is the discipline that studies data: its collection, organization, analysis, interpretation, and presentation. It provides methods to describe data, estimate population characteristics, test hypotheses, and quantify uncertainty. Statistics rests on probability theory and mathematical modeling, and it supports evidence-based decision making across fields.

Descriptive statistics summarize the main features of a data set, using measures such as mean, median, mode, variance and standard deviation, as well as graphical displays like histograms and box plots.

Inferential statistics uses information from samples to draw conclusions about larger populations. It relies on probability models to quantify uncertainty and to make inferences through estimation (point and interval estimates) and hypothesis testing, with common tools including regression analysis, analysis of variance, time-series, and multivariate methods. Bayesian statistics offers an alternative framework to incorporate prior information.

Data types: statistics deals with qualitative (categorical) and quantitative (numerical) data. Scales of measurement include nominal, ordinal, interval, and ratio, which influence suitable methods.

Applications are widespread: sciences, health, engineering, economics, public policy, quality control, market research, and sports analytics. Statistics also underpins data science, enabling data wrangling, modeling, and interpretation.

History: probabilistic ideas date to early gambling problems and demography; modern statistics developed in the 19th and 20th centuries with contributors such as Fisher, Neyman, Pearson, and Cochran, who formalized experimental design and hypothesis testing.