opls-class {ropls} | R Documentation

## Class "opls"

### Description

An S4 class to store PCA and (O)PLS(-DA) models: Objects can be created by calls of the form `new("opls", ...)` or by calling the `opls` function

### Slots

`typeC`

  character: model type (PCA, PLS, PLS-DA, OPLS, or OPLS-DA)

`descriptionMC`

  character matrix: Description of the data set (number of samples, variables, etc.)

`modelDF`

  data frame with the model overview (number of components, R2X, R2X(cum), R2Y, R2Y(cum), Q2, Q2(cum), significance, iterations)

`summaryDF`

  data frame with the model summary (cumulated R2X, R2Y and Q2); RMSEE is the square root of the mean error between the actual and the predicted responses

`subsetVi`

  Integer vector: Indices of observations in the training data set

`pcaVarVn`

  PCA: Numerical vector of variances of length: predI

`vipVn`

  PLS(-DA): Numerical vector of Variable Importance in Projection; OPLS(-DA): Numerical vector of Variable Importance for Prediction (VIP4,p from Galindo-Prieto et al, 2014)

`orthoVipVn`

  OPLS(-DA): Numerical vector of Variable Importance for Orthogonal Modeling (VIP4,o from Galindo-Prieto et al, 2014)

`coefficientMN`

  (O)PLS(-DA): Numerical matrix of regression coefficients (B; dimensions: ncol(x) x number of responses; B = W*C' and Y = XB + F

`xMeanVn`

  Numerical vector: variable means of the 'x' matrix

`xSdVn`

  Numerical vector: variable standard deviations of the 'x' matrix

`yMeanVn`

  (O)PLS: Numerical vector: variable means of the 'y' response (transformed into a dummy matrix in case it is of 'character' mode initially)

`ySdVn`

  (O)PLS: Numerical vector: variable standard deviations of the 'y' response (transformed into a dummy matrix in case it is of 'character' mode initially)

`xZeroVarVi`

  Numerical vector: indices of variables with variance < 2.22e-16 which were excluded from 'x' before building the model

`scoreMN`

  Numerical matrix of x scores (T; dimensions: nrow(x) x predI) X = TP' + E; Y = TC' + F

`loadingMN`

  Numerical matrix of x loadings (P; dimensions: ncol(x) x predI) X = TP' + E

`weightMN`

  (O)PLS: Numerical matrix of x weights (W; same dimensions as loadingMN)

`orthoScoreMN`

  OPLS: Numerical matrix of orthogonal scores (Tortho; dimensions: nrow(x) x number of orthogonal components)

`orthoLoadingMN`

  OPLS: Numerical matrix of orthogonal loadings (Portho; dimensions: ncol(x) x number of orthogonal components)

`orthoWeightMN`

  OPLS: Numerical matrix of orthogonal weights (same dimensions as orthoLoadingMN)

`cMN`

  (O)PLS: Numerical matrix of Y weights (C); dimensions: number of responses or number of classes in case of qualitative response with more than 2 classes x number of predictive components; Y = TC' + F

`coMN`

  (O)PLS: Numerical matrix of Y orthogonal weights; dimensions: number of responses or number of classes in case of qualitative response with more than 2 classes x number of orthogonal components

`uMN`

  (O)PLS: Numerical matrix of Y scores (U; same dimensions as scoreMN); Y = UC' + G

`weightStarMN`

  Numerical matrix of projections (W*; same dimensions as loadingMN); whereas columns of weightMN are derived from successively deflated matrices, columns of weightStarMN relate to the original 'x' matrix: T = XW*; W*=W(P'W)inv

`suppLs`

  List of additional objects to be used internally by the 'print', 'plot', and 'predict' methods

`eset`

  ExpressionSet: when 'opls' has been applied to an ExpressionSet, the instance with additional columns in pData containing the scores and predictions, and in fData containing the loadings, VIP, coefficients is stored here

### Objects from the Class

Objects can be created by calls of the form `new("opls", ...)` or by calling the `opls` function

### Author(s)

Etienne Thevenot, etienne.thevenot@cea.fr

Etienne Thevenot, etienne.thevenot@cea.fr

### See Also

`opls`

### Examples

    #### PCA

    data(foods) ## see Eriksson et al. (2001); presence of 3 missing values (NA)
    head(foods)
    foodMN <- as.matrix(foods[, colnames(foods) != "Country"])
    rownames(foodMN) <- foods[, "Country"]
    head(foodMN)
    foo.pca <- opls(foodMN)

    #### PLS with a single response

    data(cornell) ## see Tenenhaus, 1998
    head(cornell)
    cornell.pls <- opls(as.matrix(cornell[, grep("x", colnames(cornell))]),
                        cornell[, "y"])

    ## Complementary graphics

    plot(cornell.pls, typeVc = c("outlier", "predict-train", "xy-score", "xy-weight"))

    #### PLS with multiple (quantitative) responses

    data(lowarp) ## see Eriksson et al. (2001); presence of NAs
    head(lowarp)
    lowarp.pls <- opls(as.matrix(lowarp[, c("glas", "crtp", "mica", "amtp")]),
                       as.matrix(lowarp[, grepl("^wrp", colnames(lowarp)) |
                                          grepl("^st", colnames(lowarp))]))

    #### PLS-DA

    data(sacurine)
    attach(sacurine)
    sacurine.plsda <- opls(dataMatrix, sampleMetadata[, "gender"])

    #### OPLS-DA

    sacurine.oplsda <- opls(dataMatrix, sampleMetadata[, "gender"], predI = 1, orthoI = NA)

    detach(sacurine)

[Package ropls version 1.18.8 Index]