panelmatch {SensoMineR} | R Documentation |
Confidence ellipses around products based on panel descriptions
Description
Comparison of panels.
Usage
panelmatch(donnee, col.p, col.j, firstvar,
alpha = 0.05, coord = c(1,2), scale.unit = TRUE, nbsimul = 500,
nbchoix = NULL, centerbypanelist = TRUE,
scalebypanelist = FALSE, name.panelist = FALSE, cex = 1,
color = NULL, hierar = NULL)
Arguments
donnee |
a list of data frames, each one made up of at least two qualitative variables (product, panelist) and a set of quantitative variables (sensory descriptors) |
col.p |
the position of the product variable (in each data frame, the same position) |
col.j |
the position of the panelist variable (in each data frame, the same position) |
firstvar |
the position of the first sensory descriptor (in each data frame, the same position) |
alpha |
the confidence level of the ellipses |
coord |
a length 2 vector specifying the components to plot |
scale.unit |
boolean, if T the descriptors are scaled to unit variance |
nbsimul |
the number of simulations (corresponding to the number of virtual panels) used to compute the ellipses |
nbchoix |
the number of panelists forming a virtual panel, by default the number of panelists in the original panel |
centerbypanelist |
boolean, if T center the data by panelist before the construction of the axes |
scalebypanelist |
boolean, if T scale the data by panelist before the construction of the axes (by default, FALSE is assigned to that parameter) |
name.panelist |
boolean, if T then the name of each panelist is displayed on the |
cex |
cf. function |
color |
a vector with the colors used; by default there are 35 colors defined |
hierar |
hierarchy in the variable (see |
Value
A list containing the following elements:
eig |
a matrix with the component of the factor analysis (in row) and the eigenvalues, the inertia and the cumulative inertia for each component |
coordinates |
a list with: the coordinates of the products with respect to the panel and to each panelists and the coordinates of the partial products with respect to the panel and to each panelists |
hotelling |
Returns a matrix with the P-values of the Hotelling's T2 tests for each pair of products: this matrix allows to find the product which are significatnly different for the 2-components sensory description |
Returns a graph of the products as well as a correlation circle of the descriptors.
Returns a graph where each product is displayed with respect to a panel and to each panelist composing
the panel; products described by the panel are displayed as square, they are displayed as circle when
they are described by each panelist.
Returns a graph where each product is circled by its confidence ellipse generated by virtual panels.
When a Multiple Factor Analysis is performed, returns a graph where each partial product is circled by its confidence ellipse generated by virtual panels.
Author(s)
Francois Husson
References
Husson F., Le Dien S. & Pages J. (2005). Confidence ellipse for the sensory profiles obtained by Principal Components Analysis. Food Quality and Preference. 16 (3), 245-250.
Pages J. & Husson F. (2005). Multiple Factor Analysis with confidence ellipses: a methodology to study the relationships between sensory and instrumental data. To be published in Journal of Chemometrics.
See Also
panellipse
, panellipse.session
Examples
## Not run:
data(chocolates)
Panel1=sensochoc[as.numeric(sensochoc[,1])<11,]
Panel2=sensochoc[as.numeric(sensochoc[,1])<21 & as.numeric(sensochoc[,1])>10,]
Panel3=sensochoc[as.numeric(sensochoc[,1])>20,]
res <- panelmatch(list(P1=Panel1,P2=Panel2,P3=Panel3), col.p = 4, col.j = 1, firstvar = 5)
## End(Not run)