# Injection Moulding data

### Description

Engel (1992) presented data from an injection-moulding experiment. An industrial Taguchi experiment was performed to study the in uence of several controllable factors on the mean value and the variation in the percentage of shrinkage of products made by injection moulding. The responses y were percentages of shrinkage of products made by injection moulding. There are seven controllable factors (A-G), in a 2^(7-4) fractional factorial design. There are 8 combinations of levels for seven controllable factors (A-G) to allow the estimates of seven main effects for controllable factors. At each setting of the controllable factors, 4 observations were obtained from a 2^(3-1) fractional factorial with three noise factors (M-O).

### Usage

1 | ```
data("injection")
``` |

### Format

A data frame with 32 observations on the following 11 variables.

`y`

percentages of shrinkage of products

`a`

a controllable factor A with levels

`1`

and`2`

`b`

a controllable factor B with levels

`1`

and`2`

`c`

a controllable factor C with levels

`1`

and`2`

`d`

a controllable factor D with levels

`1`

and`2`

`e`

a controllable factor E with levels

`1`

and`2`

`f`

a controllable factor F with levels

`1`

and`2`

`g`

a controllable factor G with levels

`1`

and`2`

`m`

a noise factor M with levels

`1`

and`2`

`n`

a noise factor N with levels

`1`

and`2`

`o`

a noise factor O with levels

`1`

and`2`

### References

Engel, J. (1992). Modelling variation in industrial experiments. Applied Statistics, 41, 579–593.