مقایسهٔ روش‌ها

	نمونه‌گیری طبقه‌بندی چندسطحی	نمونه‌گیری نظام‌مند
حوزه	روش‌شناسی پیمایش	روش‌شناسی پیمایش
خانواده	Process / pipeline	Process / pipeline
سال پیدایش	1950s–1970s	Mid-20th century (Cochran 1953; Kish 1965)
پدیدآور	Formalized by Leslie Kish and William G. Cochran in the mid-20th century survey sampling literature	William G. Cochran; formalized in survey sampling theory
نوع	Probability sampling design	Probability sampling design
منبع بنیادین	Cochran, W. G. (1977). Sampling Techniques (3rd ed.). John Wiley & Sons. ISBN: 978-0471162407	Cochran, W. G. (1977). Sampling Techniques (3rd ed.). John Wiley & Sons. ISBN: 978-0471162407
نام‌های دیگر	hierarchical stratified sampling, nested stratified sampling, multilevel stratified design, stratified multilevel sampling	interval sampling, systematic random sampling, equal-interval sampling, fixed-interval sampling
مرتبط	6	5
خلاصه	Multi-level stratified sampling applies stratification at two or more hierarchical levels of a nested population structure — for example, first stratifying geographic regions, then stratifying schools within each region, then stratifying classrooms within each school. This layered control over the composition of the sample at every level reduces variance and supports analysis at each level of the hierarchy, making it a powerful design for large-scale educational, epidemiological, and organizational surveys.	Systematic sampling is a probability sampling technique in which every k-th element is selected from an ordered list of the population after a random starting point. With population size N and desired sample size n, the sampling interval k = N/n is computed and one unit is chosen at random from the first interval; all subsequent units are selected by adding k repeatedly. The method is operationally simple, yields a spread-out sample, and often achieves lower variance than simple random sampling when the list has no harmful periodicity.