Viscosity for aircraft primer paint data
viscosity.Rd"The viscosity of an aircraft primer paint is an important quality characteristic. The product is produced in batches, and because each batch takes several hours to produce, the production rate is too slow to allow for rational subgroups of size greater than one." (Montgomery, 2005, p. 232)
Usage
data(viscosity)Format
A data frame with 35 observations on the following 3 variables.
- batch
batch number
- viscosity
viscosity measure
- trial
preliminary sample indicator (TRUE/FALSE)
References
Montgomery, D.C. (2005) Introduction to Statistical Quality Control, 5th ed, New York, John Wiley & Sons, pp. 232-235
Examples
data(viscosity)
describe(viscosity, by = trial)
#> ── trial = FALSE ───────────────────────────────────────────────────────────────
#> Obs Mean StdDev Min Median Max
#> batch 15 28.00 4.4721 21.00 28.00 35.0
#> viscosity 15 34.44 0.5736 33.27 34.55 35.4
#>
#> ── trial = TRUE ────────────────────────────────────────────────────────────────
#> Obs Mean StdDev Min Median Max
#> batch 20 10.50 5.9161 1.00 10.50 20.00
#> viscosity 20 34.09 0.5694 33.27 34.03 35.96
plot(viscosity ~ batch, data = viscosity, type = "o",
pch = ifelse(trial, 19, 1))
