scalebypanelist function

Scale by panelist

Returns a data frame with entries the means of the products over the sessions for the whole panel and for each panelist.

scalebypanelist(matrice, center = TRUE, scale = FALSE, col.p, 
    col.j, firstvar, lastvar = ncol(matrice), method = "coeff")

Arguments

• matrice: a data frame made up of at least two qualitative variables (product, panelist) and a set of quantitative variables (sensory descriptors)
• center: boolean, if T scores given by panelists are centered
• scale: boolean, if T scores given by panelists are scaled to unit varaince
• col.p: the position of one categorical variables of interest (the product variable)
• col.j: the position of one categorical variables of interest (the panelist variable)
• firstvar: the position of the first endogenous variable
• lastvar: the position of the last endogenous variable (by default the last column of donnee)
• method: the method to replace the missing values: "average" or "coeff" (coefficients of the product variable in the anova model)

Returns

Returns a data frame of dimension (p(1+j),k+2*), where p is the number of products, j the number of panelists, and k the number of sensory descriptors (the first two variables correspond to the panelist and the product variables). This data frame contains the means of the products over the sessions for the whole panel and for each panelist (data may be scaled to unit variance or not, this parameter is set by users).

Author(s)

Francois Husson

Examples

data(chocolates)
res=scalebypanelist(sensochoc, col.p = 4, col.j = 1, firstvar = 5)
res