Survey Data is data collected from a well considered sample of individual units or measuring points to construct a reliable description of the reality. In human research statistical survey methodology is used to collect data from a sample of individuals to describe a population. In land surveying spatial measurements are collected to construct a spatial representation of the physical reality. Surveys are also conducted in other domains for example to model geological of hydrographic fenomena, to investigate the market or to make an inventory of the agricultural production.
Surveys can be used to create a complete inventory or a register for administrative purposes (Administrative Data). Though generally surveys do not intend to collect all the information. Instead of aiming for completeness, survey data aims to be representative. Survey Data contains only partial information but is used to reliably infer, model or represent the whole.
Using Survey Data therefore requires attention to the collection methodology, response rates, representativity of the sample individuals or sample measures and knowledge of statistical inference, modeling and representation techniques.