手法を比較

	実地体系的サンプリング	系統抽出法
分野	調査方法論	調査方法論
系統	Process / pipeline	Process / pipeline
提唱年	1940s–1950s (systematic sampling foundations); field adaptations consolidated by 1970s	Mid-20th century (Cochran 1953; Kish 1965)
提唱者	William G. Cochran (systematic sampling foundations); adapted to field contexts in ecological and agricultural survey literature	William G. Cochran; formalized in survey sampling theory
種類	Probability sampling design	Probability sampling design
原典	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
別名	systematic field sampling, grid-based field sampling, regular interval field sampling	interval sampling, systematic random sampling, equal-interval sampling, fixed-interval sampling
関連	6	5
概要	Field-based systematic sampling applies systematic (regular-interval) selection to real-world field environments — plots of land, transects, geographic grids, or physical survey routes. A random starting point is chosen, then every k-th unit or location is sampled at equal spatial or sequential intervals. Widely used in ecology, agriculture, environmental science, and field surveys, it delivers spatially even coverage at low operational cost while maintaining probability-sampling properties.	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.