เปรียบเทียบวิธี

	กฎของลิตเติล (L = λW)	Six Sigma DMAIC
สาขาวิชา	การวิจัยดำเนินงาน	การจัดการคุณภาพ
ตระกูล	Regression model	Process / pipeline
ปีกำเนิด	1961	2014
ผู้ริเริ่ม	John D. C. Little	Motorola; Pyzdek & Keller
ประเภท	Exact queueing identity	Structured process improvement methodology
แหล่งต้นตำรับ	Little, J. D. C. (1961). A proof for the queuing formula: L = λW. Operations Research, 9(3), 383–387.	Pyzdek, T., & Keller, P. (2014). The Six Sigma Handbook (4th ed.). McGraw-Hill. ISBN: 978-0-07-184053-9
ชื่อเรียกอื่น	L = λW Theorem, Little's Theorem, Little's Result, Little Yasası	DMAIC Framework, Six Sigma Process Improvement Cycle, Define-Measure-Analyze-Improve-Control, Altı Sigma DMAIC
ที่เกี่ยวข้อง	3	3
สรุป	Little's Law is a fundamental theorem in queueing theory that relates the long-run average number of items in a stable system (L) to the long-run average arrival rate (λ) and the long-run average time an item spends in the system (W), expressed as L = λW. Introduced and rigorously proved by John D. C. Little in 1961, the law holds for virtually any stable stochastic system, requiring no assumptions about arrival distributions, service distributions, or queue disciplines.	Six Sigma DMAIC is a data-driven, five-phase process improvement methodology — Define, Measure, Analyze, Improve, and Control — used to reduce defects and process variation to fewer than 3.4 defects per million opportunities. Originating at Motorola in the 1980s and systematized by practitioners including Pyzdek and Keller, it is widely adopted in manufacturing, healthcare, finance, and service industries seeking sustained quality gains.