boxprod function

Boxplot per category with respect to a categorical variable and a set of quantitative variables

Returns as many boxplots as there are categories for a given categorical variable of interest (in most cases, the product variable). The boxplots are automatically generated for all the quantitative variables (in our type of applications, variables are often sensory descriptors).

boxprod(donnee, col.p, firstvar, lastvar = ncol(donnee), 
    numr = 2, numc = 2)

Arguments

• donnee: a data frame
• col.p: the position of the categorical variable of interest
• firstvar: the position of the first endogenous variable
• lastvar: the position of the last endogenous variable (by default the last column of donnee)
• numr: the number of boxplots per row (by default 2)
• numc: the number of boxplots per column (by default 2)

Details

Missing values are ignored when forming boxplots.

References

Becker, R. A., Chambers, J. M. and Wilks, A. R. (1988) The New S Language. Wadsworth & Brooks/Cole.

Chambers, J. M., Cleveland, W. S., Kleiner, B. and Tukey, P. A. (1983) Graphical Methods for Data Analysis. Wadsworth & Brooks/Cole.

Author(s)

F Husson francois.husson@institut-agro.fr

S Le Sebastien.Le@agrocampus-ouest.fr

See Also

boxplot which does the computation, bxp for the plotting and more examples; and stripchart

for an alternative (with small data sets).

Examples

data(chocolates)
boxprod(sensochoc, col.p = 4, firstvar = 5, numr = 2, numc = 2)