solder
AT&T Solder Experiment
Description
The solder data frame, a design object, contains 900 observations
(rows), which are the results an
experiment varying 5
factors relevant to the wave-soldering procedure for mounting
components on printed circuit boards. The response variable, skips
is a count of how many solder skips appeared to a visual inspection.
The solder.balance data frame,
contains 720 rows representing a balanced subset of
all the experimental runs. The variables (columns) are the same; it is
also a design object.
The solder2 contains 750 observations which are the results of a similar
experiment incorporating some of the knowledge gained in the first.
The factors still have the same names and it is still a design object.
These data frames contains the following columns:
Arguments
| Opening |
ordered factor indicating the amount of clearance around the mounting
pad (`S < M < L').
|
| Solder |
ordered factor indicating the amount of solder used (`Thin < Thick').
|
| Mask |
factor indicating which of 5 types of solder mask was used. The
type and thickness of the material used for the mask were varied. The
levels are A1.5 , A3 , A6 , B3 , and B6 .
|
| PadType |
factor indicating which of 10 mounting pads was used. The geometry
and size of the mounting pad were varied. The
levels are W4 , D4 , L4 , D6 , L6 , D7 , L7 , L8 , W9 , and L9 .
|
| Panel |
factor indicating which of panels 1 , 2 or 3 on a board is being counted.
|
| skips |
numeric vector giving the number of visible solder skips on a circuit board.
|
Source
Comizzoli, R. B, Landwehr, J. M., and Sinclair, J. D. (1990)
Robust Materials and Processes:
Key to Reliability. AT&T Technical Journal Vol. 69, No. 6, pp. 113--128.
John M. Chambers and Trevor J. Hastie, Statistical Models in S,
Wadsworth and Brooks, Pacific Grove, CA 1992, pg. 7.
Examples
data(solder.balance)
fit1 <- aov(sqrt(skips) ~ ., data=solder.balance)
fit2 <- aov(sqrt(skips) ~ .^2, data=solder.balance)