ControlRuleSets.WesternElectric Property

public static ControlRuleSet WesternElectric { get; }

Public Shared ReadOnly Property WesternElectric As ControlRuleSet
	Get

public:
static property ControlRuleSet^ WesternElectric {
	ControlRuleSet^ get ();
}

static member WesternElectric : ControlRuleSet with get

Property Value

The shipped Western Electric preset evaluates the following four rules:

• PointBeyondControlLimits — one point strictly beyond ±3σ (window length 1). Equivalent to Nelson rule 1 / WE1.
• TwoOfThreeBeyondTwoSigmaSameSide — two out of three consecutive points beyond ±2σ on the same side (window length 3). Equivalent to Nelson rule 5 / WE3.
• FourOfFiveBeyondOneSigmaSameSide — four out of five consecutive points beyond ±1σ on the same side (window length 5). Equivalent to Nelson rule 6 / WE4.
• ConsecutivePointsOnSameSide(Int32) with run length 8 — eight consecutive points on the same side of the center line (window length 8). Note: the Western Electric handbook uses run length 8 while the Nelson standard uses run length 9.

Appropriate for general-purpose variables charts. Not recommended for attribute charts (P, NP, C, U) where zone rules produce excessive false alarms due to non-normality. Use AttributeConservative for those families.

Reference