手法を比較

	シングルブラインドA/Bテスト	ブロック化A/Bテスト
分野	実験計画法	実験計画法
系統	Process / pipeline	Process / pipeline
提唱年	mid-20th century (blinded RCT framework); A/B test nomenclature ~1990s–2000s	1926 (blocking principle); 2000s–2010s (online A/B testing application)
提唱者	Fisher, R. A. (randomisation basis); blinding practice formalised in clinical trials mid-20th century	R. A. Fisher (blocking principle); adapted to online A/B testing by industry practitioners
種類	Controlled experiment with partial blinding	Randomized controlled experiment with variance reduction
原典	Kohavi, R., Tang, D., & Xu, Y. (2020). Trustworthy Online Controlled Experiments: A Practical Guide to A/B Testing. Cambridge University Press. ISBN: 978-1108724265	Fisher, R. A. (1926). The arrangement of field experiments. Journal of the Ministry of Agriculture of Great Britain, 33, 503–513.
別名	single-masked A/B test, single-blind split test, blinded two-condition experiment, participant-blind A/B test	block-randomized A/B test, stratified A/B test, blocked split test, block-design A/B experiment
関連	6	4
概要	A single-blind A/B test is a controlled two-condition experiment in which participants are randomised to condition A (control) or condition B (treatment) but are kept unaware of which condition they have received, while researchers and analysts remain aware. The blind prevents participants from changing their behaviour in response to knowledge of their assignment, reducing demand characteristics and response bias while still allowing the investigator to monitor the trial.	A blocked A/B test is an experimental design that partitions units (users, subjects, or clusters) into homogeneous blocks before randomly assigning them to treatment A or treatment B within each block. Blocking reduces within-experiment noise by ensuring that known sources of variation — such as device type, geography, or user tenure — are balanced across conditions, yielding more precise estimates of the treatment effect than a simple unblocked A/B test.