we_rules {XRSCC}

Estimates the first four Western Electric Rules for detecting patterns

Description

Estimates the first four Western Electric Rules for detecting patterns, starting with under control X chart obtained in the sequence xrs_gr, X_it, R_it functions. At the same time, plots the X chart including the zones above and below the central limit. For last, a binary value for each rule is presented if at least one rule is violated, '1' for 'yes', 0 for 'no'.

Usage

we_rules(prev.results)

Arguments

prev.results

Its a list of previous results obtained by the xrs_gr function in the first iteration, or a list of results obtained in further iterations by the X_it, and if necessary by the R_it function.

Details

The previous results may say that the process is under control, but, it's a conclusion concerning the first Western Electric rule only.

Value

Resultados de analisis

A phrarse saying the process is or not under control

Las siguientes reglas tienen al menos un grupo que viola la regla

The conclussion about the Western Electric rules from 1 to 4, showing a binary response, '1' for 'yes', 0 for 'no'.

Author(s)

Erick Marroquin

References

Montgomery, D.C. (2005) Introduction to Statistical Quality Control, 5th ed. New York: John Wiley & Sons, ISBN 0-471-65631-3

SMALL, Bonnie B. (1956) Statistical Quality Control Handbook, 2th ed. Easton : Western Electric Co, Inc.

yhat The Yhat Blog. Machine Learning, Data Science, Engineering, [On line] http://blog.yhathq.com/posts/quality-control-in-r.html

See Also

xrs_gr, X_it, R_it, Cp_X

Examples

data(qqsugar)
results1<-xrs_gr(qqsugar)
results2<-R_it(results1)
we_rules(results2)