SixSigma (version 0.7-0)

ss.lfa: Loss Function Analysis

Description

This function performs a Quality Loss Function Analysis, based in the Taguchi Loss Function for "Nominal-the-Best" characteristics.

Usage

ss.lfa(lfa.data, lfa.ctq, lfa.Delta, lfa.Y0, lfa.L0,
    lfa.size = NA, lfa.output = "both",
    lfa.sub = "Six Sigma Project")

Arguments

lfa.data

Data frame with the sample to get the average loss.

lfa.ctq

Name of the field in the data frame containing the data.

lfa.Delta

Tolerance of the process.

lfa.Y0

Target of the process (see note).

lfa.L0

Cost of poor quality at tolerance limit.

lfa.size

Size of the production, batch, etc. to calculate the total loss in a group (span, batch, period, ...)

lfa.output

Type of output (see details).

lfa.sub

Subtitle for the graphic output.

Value

• lfa.k
  Constant k for the loss function
• lfa,lf
  Expression with the loss function
• lfa.MSD
  Mean Squared Differences from the target
• lfa.avLoss
  Average Loss per unit of the process
• lfa.Loss
  Total Loss of the process (if a size is provided)

Details

lfa.output can take the values "text", "plot" or "both".

References

Taguchi G, Chowdhury S,Wu Y (2005) Taguchi's quality engineering handbook. John Wiley Cano, Emilio L., Moguerza, Javier M. and Redchuk, Andres. 2012. Six Sigma with {R}. Statistical Engineering for Process Improvement, Use R!, vol. 36. Springer, New York. http://www.springer.com/statistics/book/978-1-4614-3651-5.

See Also

ss.lf, ss.data.bolts.

Examples

ss.lfa(ss.data.bolts, "diameter", 0.5, 10, 0.001,
		lfa.sub = "10 mm. Bolts Project",
		lfa.size = 100000, lfa.output = "both")