Statistics Symbols

R

The subgroup range (highest minus lowest value).

R = R-Bar

The average range of a series of subgroups of constant size.

s = sigma = s

Sample Standard Deviation

SL

A unilateral engineering specification unit.

u

The number of nonconformities per unit in a sample which may contain more than 1 unit.

u = u-Bar

The average number of nonconformities per unit in samples not necessarily of the same size.

UCL

The upper control limit.

USL

The upper engineering specification limit.

x

An individual value upon which other subgroup statistics are based.

x = x-Bar

The average of values in a subgroup.

x = x-Double bar

The average of subgroup averages (weighted, if necessary, by sample size). The measured process average.

Sigma = Standard Deviation = s

The standard deviation of the distribution of individual values of a process characteristic.

s = Sigma-Hat

An estimate of the standard deviation of a process characteristic.

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The Juran Trilogy	The Deming PDCA Cycle	QMS Implementation	FMEA Information	APQP Information
Auditing Information	8-D Problem Solving	Statistics	Error Proofing (Poka Yoke)	Brainstorming
Identifying Waste	Pull Systems	Lead Time Reduction	Planned Maintenance	Quick Setup
Discovering Change	Process Capability - Cp vs. Cpk	Histogram Animation	Process Loop Animation	Taguchi Loss Function
		Fishbone / Cause and Effects Animation

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