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statmod (version 1.4.26)

welding: 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)

Arguments

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.

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.