Probabilistic sampling principle

Market research method A desk research case study method B non-repeated sampling method C sampling survey reset sampling lottery method D multi-dimensional scale quantitative research legal research method Typical survey method Telephone survey Multi-stage sampling equidistant sampling independent control quota sampling equidistant scale equal scale E Second-hand data survey Two-way focus group F non-probability sampling stratified proportional sampling stratified optimal sampling G observation method Probability sampling inflection point survey Snowball sampling H meeting survey J focus interview method Empirical judgment method Feasibility study of random sampling family diary method dealer interview K L joint analysis method lien survey garbage survey method category scale M interview interview method blind descriptive survey P PPS judgment sampling quota sampling balance scale evaluation scale pairing comparison scale Q classification R random sampling S capacity measurement SEM model in-depth interview double sampling experimental survey field survey numerical distribution scale random number table sequence scale T projection technology sales estimation projection research W literature survey questionnaire survey network survey copywriting survey not ready to visit network survey X inquiry syndicate survey destination analysis mutual control quota sampling. Y-mail survey causality survey Z- subjective probability method cluster sampling focus survey door-to-door search method probability sampling can ensure the representativeness of the group, and its principle is that it can well form samples according to the probability of various random events contained in the internal structure of the group, making the samples a microcosm of the group.