welding {statmod}

Data: Tensile Strength of Welds

Description

This is a highly fractionated two-level factorial design employed as a screening design in an off-line welding experiment performed by the National Railway Corporation of Japan. There were 16 runs and 9 experimental factors. The response variable is the observed tensile strength of the weld, one of several quality characteristics measured. All other variables are at plus and minus levels.

Usage

data(welding)

Format

A data frame containing the following variables. All the explanatory variables are numeric with two levels, -1 and 1.

	Variable	Description
	Rods	Kind of welding rods
	Drying	Period of drying
	Material	Welded material
	Thickness	Thickness
	Angle	Angle
	Opening	Opening
	Current	Current
	Method	Welding method
	Preheating	Preheating
	Strength	Tensile strength of the weld in kg/mm. The response variable.

Source

http://www.statsci.org/data/general/welding.html

References

Smyth, G. K., Huele, F., and Verbyla, A. P. (2001). Exact and approximate REML for heteroscedastic regression. Statistical Modelling 1, 161-175.

Smyth, G. K. (2002). An efficient algorithm for REML in heteroscedastic regression. Journal of Computational and Graphical Statistics 11, 1-12.