Sampling Error Estimation for Complex Surveys // Estimates sampling errors and produces indicator tables for complex survey data. Supports weighted totals, proportions, standard errors, confidence intervals, coefficients of variation, design effects, unweighted frequencies, grouped estimates, domain estimates, optional stratification and clustering variables, and customizable exports to '.xlsx' files. Survey estimation is based on design-based inference using Taylor series linearization implemented in the 'survey' package (Lumley, 2004, doi:10.18637/jss.v009.i08; Lumley, 2010, ISBN:9780470284308). The package provides a reproducible workflow for official statistics, household surveys, and applied survey research.