Package 'plspm'

Title: Tools for Partial Least Squares Path Modeling (PLS-PM)
Description: Partial Least Squares Path Modeling (PLS-PM) analysis for both metric and non-metric data, as well as REBUS analysis for latent class detection.
Authors: Gaston Sanchez [aut, cre], Laura Trinchera [aut], Giorgio Russolillo [aut]
Maintainer: Gaston Sanchez <[email protected]>
License: GPL-3
Version: 0.4.9
Built: 2024-09-04 04:37:25 UTC
Source: https://github.com/gastonstat/plspm

Help Index


Cronbach's alpha

Description

Cronbach's alpha of a single block of variables

Usage

alpha(X)

Arguments

X

matrix representing one block of manifest variables

Value

Cronbach's alpha

Author(s)

Gaston Sanchez

See Also

rho, unidim

Examples

## Not run: 
 # load dataset satisfaction
 data(satisfaction)

 # block Image (first 5 columns of satisfaction)
 Image = satisfaction[,1:5]

 # compute Cronbach's alpha for Image block
 alpha(Image)
 
## End(Not run)

Arizona vegetation dataset

Description

This dataset gives the measurements of 16 vegetation communitites in the Santa Catalina Mountains, Arizona. The measurements were taken along different elevations from fir forest at high elevations, through pine forest, woodlands, and desert grassland.

Usage

arizona

Format

A data frame with 16 observations and 8 variables. The variables refer to three latent concepts: 1) ENV=environment, 2) SOIL=soil, and 3) DIV=diversity.

Num Variable Description Concept
1 env.elev Elevation (m) environment
2 env.incli Terrain inclination (degrees) environment
3 soil.ph Acidity and base saturation soil
4 soil.orgmat Organic matter content (perc) soil
5 soil.nitro Nitrogen content (perc) soil
6 div.trees Number of species of trees diversity
7 div.shrubs Numer of species of shrubs diversity
8 div.herbs Number of species of herbs diversity

The complete name of the rows are: 1) Abies lasiocarpa, 2) Abies concolor, 3) Pseudotsuga menziesii-Abies Concolor, 4) Pseudotsuga menziesii, 5) Pinus ponderosa-Pinus strobiformis, 6) Pinus ponderosa, 7) Pinus ponderosa-Quercus, 8) Pinus chihuahuana, 9) Pygmy conifer-oak scrub, 10) Open oak woodland, 11) Bouteloua curtipendula, 12) Spinose-suffrutescent, 13) Cercidium microphyllum, 14) Larrea divaricata, 15) Cercocarpus breviflorus, 16) Populus tremuloides.

Source

Mixed data from Whittaker et al (1968), and Whittaker and Niering (1975). See References below.

References

Whittaker, R. H., Buol, S. W., Niering, W. A., and Havens, Y. H. (1968) A Soil and Vegetation Pattern in the Santa Catalina Mountains, Arizona. Soil Science, 105, pp. 440-450.

Whittaker, R. H., and Niering, W. A. (1975) Vegetation of the Santa Catalina Mountains, Arizona. V. Biomass, Production, and Diversity Along the Elevation Gradient. Ecology, 56, pp. 771-790.

Examples

data(arizona)
  arizona

Cereals datset

Description

Data with several variables of different brands of cereal

Usage

data(cereals)

Format

A data frame with 77 observations on the following 15 variables.

mfr

Manufacturer of cereal

type

type: cold or hot

calories

calories per serving

protein

grams of protein

fat

grams of fat

sodium

milligrams of sodium

fiber

grams of dietary fiber

carbo

grams of complex carbohydrates

sugars

grams of sugars

potass

milligrams of potassium

vitamins

vitamins and minerals - 0, 25, or 100, indicating the typical percentage of FDA recommended

shelf

display shelf (1, 2, or 3, counting from the floor)

weight

weight in ounces of one serving

cups

number of cups in one serving

rating

a rating of the cereals

Source

http://lib.stat.cmu.edu/DASL/Datafiles/Cereals.html

References

http://lib.stat.cmu.edu/DASL/Stories/HealthyBreakfast.html

Examples

# load data
data(cereals)

# take a peek
head(cereals)

College datasets

Description

Dataset with different scores (high school, undergrad basic, undergrad intermediate, and GPA) of graduated college student in life sciences majors

Usage

data(college)

Format

A data frame with 352 students on the following 13 variables. The variables may be used to construct four suggested latent concepts: 1) HighSchool=High School related scores, 2) Basic=scores of basic courses, 3) InterCourse=Scores of intermediate courses, 4) GPA=Final GPA (Graduate Point Average)

Num Variable Description Concept
1 HS_GPA High School GPA HighSchool
2 SAT_Verbal Verbal SAT score HighSchool
3 SAT_Math Math SAT score HighSchool
4 Biology1 Introductory Biology BasicCourses
5 Chemistry1 Introductoy Chemistry BasicCourses
6 Math1 Calculus 1 BasicCourses
7 Physics1 Introductory Physics BasicCourses
8 Biology2 Intermediate Biology InterCourses
9 Chemistry2 Intermediate Chemistry InterCourses
10 Math2 Calculus 2 InterCourses
11 Physics2 Intermediate Physics InterCourses
12 FinalGPA Graduation GPA FinalGPA
13 Gender Gender none

Examples

# load data
data(college)

# take a peek
head(college)

Futbol dataset from Spain-England-Italy

Description

This data set contains the results of the teams in the Spanish, English, and Italian football leagues 2009-2010 season.

Usage

data(futbol)

Format

A data frame with 60 observations on the following 12 variables. The variables may be used to construct three latent concepts: 1) ATTACK=Attack, 2) DEFENSE=Defense, 3) SUCCESS=Success.

Num Variable Description Concept
1 GSH: Goals Scored at Home total number of goals scored at home ATTACK
2 GSA: Goals Scored Away total number of goals scored away ATTACK
3 SSH: Success to Score at Home percentage of matches with scores goals at home ATTACK
4 SSA: Success to Score Away percentage of matches with scores goals away ATTACK
5 NGCH: Goals Conceded at Home total number (negative) of goals conceded at home DEFENSE
6 NGCA: Goals Conceded Away total number (negative) of goals conceded away DEFENSE
7 CSH: Clean Sheets at Home percentage of matches with no conceded goals at home DEFENSE
8 CSA: Clean Sheets Away percentage of matches with no conceded goals away DEFENSE
9 WMH: Won Matches at Home total number of matches won at home SUCCESS
10 WMA: Won Matches Away total number of matches won away SUCCESS
11 Country: Leangue Country country of the team's league none
12 Rank: Rank Position final ranking position within its league none

Source

League Day. http://www.leagueday.com
Statto. http://www.statto.com

Examples

data(futbol)
  futbol

Plot inner model

Description

Plot the inner (structural) model for objects of class "plspm", as well as path matrices

Usage

innerplot(x, colpos = "#6890c4BB", colneg = "#f9675dBB",
    box.prop = 0.55, box.size = 0.08, box.cex = 1,
    box.col = "gray95", lcol = "gray95", box.lwd = 2,
    txt.col = "gray50", shadow.size = 0, curve = 0,
    lwd = 3, arr.pos = 0.5, arr.width = 0.2, arr.lwd = 3,
    cex.txt = 0.9, show.values = FALSE, ...)

Arguments

x

Either a matrix defining an inner model or an object of class "plspm".

colpos

Color of arrows for positive path coefficients.

colneg

Color of arrows for negative path coefficients.

box.prop

Length/width ratio of ellipses.

box.size

Size of ellipses.

box.cex

Relative size of text in ellipses.

box.col

fill color of ellipses,

lcol

border color of ellipses.

box.lwd

line width of the box.

txt.col

color of text in ellipses.

shadow.size

Relative size of shadow of label box.

curve

arrow curvature.

lwd

line width of arrow.

arr.pos

Relative position of arrowheads on arrows.

arr.width

arrow width.

arr.lwd

line width of arrow, connecting two different points, (one value, or a matrix with same dimensions as x).

cex.txt

Relative size of text on arrows.

show.values

should values be shown when x is a matrix.

...

Further arguments passed on to plotmat.

Note

innerplot uses the function plotmat in package diagram.
http://cran.r-project.org/web/packages/diagram/vignettes/diagram.pdf

See Also

plot.plspm, outerplot


Iterative steps of Response-Based Unit Segmentation (REBUS)

Description

REBUS-PLS is an iterative algorithm for performing response based clustering in a PLS-PM framework. it.reb allows to perform the iterative steps of the REBUS-PLS Algorithm. It provides summarized results for final local models and the final partition of the units. Before running this function, it is necessary to run the res.clus function to choose the number of classes to take into account.

Usage

it.reb(pls, hclus.res, nk, Y = NULL, stop.crit = 0.005,
    iter.max = 100)

Arguments

pls

an object of class "plspm"

hclus.res

object of class "res.clus" returned by res.clus

nk

integer larger than 1 indicating the number of classes. This value should be defined according to the dendrogram obtained by performing res.clus.

Y

optional data matrix used when pls$data is NULL

stop.crit

Number indicating the stop criterion for the iterative algorithm. It is suggested to use the threshold of less than 0.05% of units changing class from one iteration to the other as stopping rule.

iter.max

integer indicating the maximum number of iterations

Value

an object of class "rebus"

loadings

Matrix of standardized loadings (i.e. correlations with LVs.) for each local model

path.coefs

Matrix of path coefficients for each local model

quality

Matrix containing the average communalities, the average redundancies, the R2 values, and the GoF index for each local model

segments

Vector defining the class membership of each unit

origdata.clas

The numeric matrix with original data and with a new column defining class membership of each unit

Author(s)

Laura Trinchera, Gaston Sanchez

References

Esposito Vinzi, V., Trinchera, L., Squillacciotti, S., and Tenenhaus, M. (2008) REBUS-PLS: A Response-Based Procedure for detecting Unit Segments in PLS Path Modeling. Applied Stochastic Models in Business and Industry (ASMBI), 24, pp. 439-458.

Trinchera, L. (2007) Unobserved Heterogeneity in Structural Equation Models: a new approach to latent class detection in PLS Path Modeling. Ph.D. Thesis, University of Naples "Federico II", Naples, Italy.

http://www.fedoa.unina.it/2702/1/Trinchera_Statistica.pdf

See Also

plspm, rebus.pls, res.clus

Examples

## Not run: 
## Example of REBUS PLS with simulated data

# load simdata
data("simdata", package='plspm')

# Calculate global plspm
sim_inner = matrix(c(0,0,0,0,0,0,1,1,0), 3, 3, byrow=TRUE)
dimnames(sim_inner) = list(c("Price", "Quality", "Satisfaction"),
                           c("Price", "Quality", "Satisfaction"))
sim_outer = list(c(1,2,3,4,5), c(6,7,8,9,10), c(11,12,13))
sim_mod = c("A", "A", "A")  # reflective indicators
sim_global = plspm(simdata, sim_inner,
                   sim_outer, modes=sim_mod)
sim_global

## Then compute cluster analysis on residuals of global model
sim_clus = res.clus(sim_global)

## To complete REBUS, run iterative algorithm
rebus_sim = it.reb(sim_global, sim_clus, nk=2,
                   stop.crit=0.005, iter.max=100)

## You can also compute complete outputs
## for local models by running:
local_rebus = local.models(sim_global, rebus_sim)

# Display plspm summary for first local model
summary(local_rebus$loc.model.1)

## End(Not run)

PLS-PM for global and local models

Description

Calculates PLS-PM for global and local models from a given partition

Usage

local.models(pls, y, Y = NULL)

Arguments

pls

An object of class "plspm"

y

One object of the following classes: "rebus", "integer", or "factor", that provides the class partitions.

Y

Optional dataset (matrix or data frame) used when argument dataset=NULL inside pls.

Details

local.models calculates PLS-PM for the global model (i.e. over all observations) as well as PLS-PM for local models (i.e. observations of different partitions).

When y is an object of class "rebus", local.models is applied to the classes obtained from the REBUS algorithm.

When y is an integer vector or a factor, the values or levels are assumed to represent the group to which each observation belongs. In this case, the function local.models calculates PLS-PM for the global model, as well as PLS-PM for each group (local models).

When the object pls does not contain a data matrix (i.e. pls$data=NULL), the user must provide the data matrix or data frame in Y.

The original parameters modes, scheme, scaled, tol, and iter from the object pls are taken.

Value

An object of class "local.models", basically a list of length k+1, where k is the number of classes.

glob.model

PLS-PM of the global model

loc.model.1

PLS-PM of segment (class) 1

loc.model.2

PLS-PM of segment (class) 2

loc.model.k

PLS-PM of segment (class) k

Note

Each element of the list is an object of class "plspm". Thus, in order to examine the results for each local model, it is necessary to use the summary function.

Author(s)

Laura Trinchera, Gaston Sanchez

See Also

rebus.pls

Examples

## Not run: 
## Example of REBUS PLS with simulated data

# load simdata
data("simdata", package='plspm')

# Calculate global plspm
sim_inner = matrix(c(0,0,0,0,0,0,1,1,0), 3, 3, byrow=TRUE)
dimnames(sim_inner) = list(c("Price", "Quality", "Satisfaction"),
                           c("Price", "Quality", "Satisfaction"))
sim_outer = list(c(1,2,3,4,5), c(6,7,8,9,10), c(11,12,13))
sim_mod = c("A", "A", "A")  # reflective indicators
sim_global = plspm(simdata, sim_inner,
                   sim_outer, modes=sim_mod)
sim_global

## Then compute cluster analysis on residuals of global model
sim_clus = res.clus(sim_global)

## To complete REBUS, run iterative algorithm
rebus_sim = it.reb(sim_global, sim_clus, nk=2,
                   stop.crit=0.005, iter.max=100)

## You can also compute complete outputs
## for local models by running:
local_rebus = local.models(sim_global, rebus_sim)

# Display plspm summary for first local model
summary(local_rebus$loc.model.1)

## End(Not run)

ECSI Mobile Phone Provider dataset

Description

This table contains data from the article by Tenenhaus et al. (2005), see reference below.

Usage

data(mobile)

Format

A data frame with 250 observations on 24 variables on a scale from 0 to 100. The variables refer to seven latent concepts: 1) IMAG=Image, 2) EXPE=Expectations, 3) QUAL=Quality, 4) VAL=Value, 5) SAT=Satisfaction, 6) COM=Complaints, and 7) LOY=Loyalty.

IMAG: Includes variables such as reputation, trustworthiness, seriousness, and caring about customer's needs.
EXPE: Includes variables such as products and services provided and expectations for the overall quality.
QUAL: Includes variables such as reliable products and services, range of products and services, and overall perceived quality.
VAL: Includes variables such as quality relative to price, and price relative to quality.
SAT: Includes variables such as overall rating of satisfaction, fulfillment of expectations, satisfaction relative to other phone providers.
COM: Includes one variable defining how well or poorly custmer's complaints were handled.
LOY: Includes variables such as propensity to choose the same phone provider again, propensity to switch to other phone provider, intention to recommend the phone provider to friends.

ima1

First MV of the block Image

ima2

Second MV of the block Image

ima3

Third MV of the block Image

ima4

Fourth MV of the block Image

ima5

Fifth MV of the block Image

exp1

First MV of the block Expectations

exp2

Second MV of the block Expectations

exp3

Third MV of the block Expectations

qua1

First MV of the block Quality

qua2

Second MV of the block Quality

qua3

Third MV of the block Quality

qua4

Fourth MV of the block Quality

qua5

Fifth MV of the block Quality

qua6

Sixth MV of the block Quality

qua7

Seventh MV of the block Quality

val1

First MV of the block Value

val2

Second MV of the block Value

sat1

First MV of the block Satisfaction

sat2

Second MV of the block Satisfaction

sat3

Third MV of the block Satisfaction

comp

First MV of the block Complaints

loy1

First MV of the block Loyalty

loy2

Second MV of the block Loyalty

loy3

Third MV of the block Loyalty

References

Tenenhaus, M., Esposito Vinzi, V., Chatelin Y.M., and Lauro, C. (2005) PLS path modeling. Computational Statistics & Data Analysis, 48, pp. 159-205.

Examples

data(mobile)

Offense dataset

Description

Dataset with offense statistics of American football teams from the NFL (2010-2011 season).

Usage

data(offense)

Format

A data frame with 32 teams on the following 17 variables. The variables may be used to construct five suggested latent concepts: 1) RUSH=Rushing Quality, 2) PASS=Passing Quality, 3) SPEC=Special Teams and Other, 4) SCORING=Scoring Success, 5)OFFENSE=Offense Performance

Num Variable Description Concept
1 YardsRushAtt Yards per Rush Attempt RUSH
2 RushYards Rush Yards per game RUSH
3 RushFirstDown Rush First Downs per game RUSH
4 YardsPassComp Yards Pass Completion PASS
5 PassYards Passed Yards per game PASS
6 PassFirstDown Pass First Downs per game PASS
7 FieldGoals Field Goals per game SPEC
8 OtherTDs Other Touchdowns (non-offense) per game SPEC
9 PointsGame Points per game SCORING
10 OffensTD Offense Touchdowns per game SCORING
11 TDGame Touchdowns per game SCORING
12 PassTDG Passing Touchdowns per game OFFENSE
13 RushTDG Rushing Touchdowns per game OFFENSE
14 PlaysGame Plays per game OFFENSE
15 YardsPlay Yards per Play OFFENSE
16 FirstDownPlay First Downs per Play OFFENSE
17 OffTimePossPerc Offense Time Possession Percentage OFFENSE

Source

http://www.teamrankings.com/nfl/stats/

Examples

# load data
data(offense)

# take a peek
head(offense)

Orange Juice dataset

Description

This data set contains the physico-chemical, sensory and hedonic measurements of 6 orange juices.

Usage

orange

Format

A data frame with 6 observations and 112 variables. The variables refer to three latent concepts: 1) PHYCHEM=Physico-Chemical, 2) SENSORY=Sensory, and 3) HEDONIC=Hedonic.

Num Variable Description Concept
1 glucose Glucose (g/l) physico-chemical
2 fructose Fructose (g/l) physico-chemical
3 saccharose Saccharose (g/l) physico-chemical
4 sweet.power Sweetening power (g/l) physico-chemical
5 ph1 pH before processing physico-chemical
6 ph2 pH after centrifugation physico-chemical
7 titre Titre (meq/l) physico-chemical
8 citric.acid Citric acid (g/l) physico-chemical
9 vitamin.c Vitamin C (mg/100g) physico-chemical
10 smell.int Smell intensity sensory
11 odor.typi Odor typicity sensory
12 pulp Pulp sensory
13 taste.int Taste intensity sensory
14 acidity Acidity sensory
15 bitter Bitterness sensory
16 sweet Sweetness sensory
17 judge1 Ratings of judge 1 hedonic
18 judge2 Ratings of judge 2 hedonic
... ... ... ...
112 judge96 Ratings of judge 96 hedonic

Source

Laboratoire de Mathematiques Appliques, Agrocampus, Rennes.

References

Tenenhaus, M., Pages, J., Ambroisine, L., and Guinot, C. (2005) PLS methodology to study relationships between hedonic jedgements and product characteristics. Food Quality and Preference, 16(4), pp. 315-325.

Pages, J., and Tenenhaus, M. (2001) Multiple factor analysis combined with PLS path modelling. Application to the analysis of relationships between physicochemical, sensory profiles and hedonic judgements. Chemometrics and Intelligent Laboratory Systems, 58, pp. 261-273.

Pages, J. (2004) Multiple Factor Analysis: Main Features and Application to Sensory Data. Revista Colombiana de Estadistica, 27, pp. 1-26.

Examples

data(orange)
  orange

Plot outer model

Description

Plot either outer weights or loadings in the outer model for objects of class "plspm"

Usage

outerplot(x, what = "loadings", colpos = "#6890c4BB",
    colneg = "#f9675dBB", box.prop = 0.55, box.size = 0.08,
    box.cex = 1, box.col = "gray95", lcol = "gray95",
    box.lwd = 2, txt.col = "gray40", shadow.size = 0,
    curve = 0, lwd = 2, arr.pos = 0.5, arr.width = 0.15,
    cex.txt = 0.9, ...)

Arguments

x

An object of class "plspm".

what

What to plot: "loadings" or "weights".

colpos

Color of arrows for positive path coefficients.

colneg

Color of arrows for negative path coefficients.

box.prop

Length/width ratio of ellipses and rectangles.

box.size

Size of ellipses and rectangles.

box.cex

Relative size of text in ellipses and rectangles.

box.col

fill color of ellipses and rectangles.

lcol

border color of ellipses and rectangles.

box.lwd

line width of the box.

txt.col

color of text in ellipses and rectangles.

shadow.size

Relative size of shadow of label box.

curve

arrow curvature.

lwd

line width of arrow.

arr.pos

Relative position of arrowheads on arrows.

arr.width

arrow width.

cex.txt

Relative size of text on arrows.

...

Further arguments passed on to plotmat.

Note

outerplot uses the function plotmat of package diagram.
http://cran.r-project.org/web/packages/diagram/vignettes/diagram.pdf

See Also

innerplot, plot.plspm, plspm


Plots for PLS Path Models

Description

Plot method for objects of class "plspm". This function plots either the inner (i.e. structural) model with the estimated path coefficients, or the outer (i.e. measurement) model with loadings or weights.

Usage

## S3 method for class 'plspm'
 plot(x, what = "inner",
    colpos = "#6890c4BB", colneg = "#f9675dBB",
    box.prop = 0.55, box.size = 0.08, box.cex = 1,
    box.col = "gray95", lcol = "gray95",
    txt.col = "gray40", arr.pos = 0.5, cex.txt = 0.9, ...)

Arguments

x

An object of class "plspm".

what

What to plot: "inner", "loadings", "weights".

colpos

Color of arrows for positive path coefficients.

colneg

Color of arrows for negative path coefficients.

box.prop

Length/width ratio of ellipses and rectangles.

box.size

Size of ellipses and rectangles.

box.cex

Relative size of text in ellipses and rectangles.

box.col

fill color of ellipses and rectangles.

lcol

border color of ellipses and rectangles.

txt.col

color of text in ellipses and rectangles.

arr.pos

Relative position of arrowheads on arrows.

cex.txt

Relative size of text on arrows.

...

Further arguments passed on to plotmat.

Details

plot.plspm is just a wraper of innerplot and outerplot.

Note

Function plot.plspm is based on the function plotmat of package diagram.
http://cran.r-project.org/web/packages/diagram/vignettes/diagram.pdf

See Also

innerplot, outerplot, plspm

Examples

## Not run: 
 ## typical example of PLS-PM in customer satisfaction analysis
 ## model with six LVs and reflective indicators
 # load data satisfaction
 data(satisfaction)

 # define inner model matrix
 IMAG = c(0,0,0,0,0,0)
 EXPE = c(1,0,0,0,0,0)
 QUAL = c(0,1,0,0,0,0)
 VAL = c(0,1,1,0,0,0)
 SAT = c(1,1,1,1,0,0)
 LOY = c(1,0,0,0,1,0)
 sat.inner = rbind(IMAG, EXPE, QUAL, VAL, SAT, LOY)

 # define outer model list
 sat.outer = list(1:5, 6:10, 11:15, 16:19, 20:23, 24:27)

 # define vector of reflective modes
 sat.mod = rep("A", 6)

 # apply plspm
 satpls = plspm(satisfaction, sat.inner, sat.outer, sat.mod, scheme="centroid",
               scaled=FALSE)

 # plot path coefficients
 plot(satpls, what="inner")

 # plot loadings
 plot(satpls, what="loadings")

 # plot outer weights
 plot(satpls, what="weights")
 
## End(Not run)

PLS-PM: Partial Least Squares Path Modeling

Description

Estimate path models with latent variables by partial least squares approach (for both metric and non-metric data)

Estimate path models with latent variables by partial least squares approach (for both metric and non-metric data)

Usage

plspm(Data, path_matrix, blocks, modes = NULL,
    scaling = NULL, scheme = "centroid", scaled = TRUE,
    tol = 1e-06, maxiter = 100, plscomp = NULL,
    boot.val = FALSE, br = NULL, dataset = TRUE)

Arguments

Data

matrix or data frame containing the manifest variables.

path_matrix

A square (lower triangular) boolean matrix representing the inner model (i.e. the path relationships between latent variables).

blocks

list of vectors with column indices or column names from Data indicating the sets of manifest variables forming each block (i.e. which manifest variables correspond to each block).

scaling

optional argument for runing the non-metric approach; it is a list of string vectors indicating the type of measurement scale for each manifest variable specified in blocks. scaling must be specified when working with non-metric variables. Possible values: "num" (linear transformation, suitable for numerical variables), "raw" (no transformation), "nom" (non-monotonic transformation, suitable for nominal variables), and "ord" (monotonic transformation, suitable for ordinal variables).

modes

character vector indicating the type of measurement for each block. Possible values are: "A", "B", "newA", "PLScore", "PLScow". The length of modes must be equal to the length of blocks.

scheme

string indicating the type of inner weighting scheme. Possible values are "centroid", "factorial", or "path".

scaled

whether manifest variables should be standardized. Only used when scaling = NULL. When (TRUE, data is scaled to standardized values (mean=0 and variance=1). The variance is calculated dividing by N instead of N-1).

tol

decimal value indicating the tolerance criterion for the iterations (tol=0.000001). Can be specified between 0 and 0.001.

maxiter

integer indicating the maximum number of iterations (maxiter=100 by default). The minimum value of maxiter is 100.

plscomp

optional vector indicating the number of PLS components (for each block) to be used when handling non-metric data (only used if scaling is provided)

boot.val

whether bootstrap validation should be performed. (FALSE by default).

br

number bootstrap resamples. Used only when boot.val=TRUE. When boot.val=TRUE, the default number of re-samples is 100.

dataset

whether the data matrix used in the computations should be retrieved (TRUE by default).

Details

The function plspm estimates a path model by partial least squares approach providing the full set of results.

The argument path_matrix is a matrix of zeros and ones that indicates the structural relationships between latent variables. path_matrix must be a lower triangular matrix; it contains a 1 when column j affects row i, 0 otherwise.

  • plspm: Partial Least Squares Path Modeling

  • plspm.fit: Simple version for PLS-PM

  • plspm.groups: Two Groups Comparison in PLS-PM

  • rebus.pls: Response Based Unit Segmentation (REBUS)

Value

An object of class "plspm".

outer_model

Results of the outer model. Includes: outer weights, standardized loadings, communalities, and redundancies

inner_model

Results of the inner (structural) model. Includes: path coeffs and R-squared for each endogenous latent variable

scores

Matrix of latent variables used to estimate the inner model. If scaled=FALSE then scores are latent variables calculated with the original data (non-stardardized).

path_coefs

Matrix of path coefficients (this matrix has a similar form as path_matrix)

crossloadings

Correlations between the latent variables and the manifest variables (also called crossloadings)

inner_summary

Summarized results of the inner model. Includes: type of LV, type of measurement, number of indicators, R-squared, average communality, average redundancy, and average variance extracted

effects

Path effects of the structural relationships. Includes: direct, indirect, and total effects

unidim

Results for checking the unidimensionality of blocks (These results are only meaningful for reflective blocks)

gof

Goodness-of-Fit index

data

Data matrix containing the manifest variables used in the model. Only available when dataset=TRUE

boot

List of bootstrapping results; only available when argument boot.val=TRUE

Author(s)

Gaston Sanchez, Giorgio Russolillo

References

Tenenhaus M., Esposito Vinzi V., Chatelin Y.M., and Lauro C. (2005) PLS path modeling. Computational Statistics & Data Analysis, 48, pp. 159-205.

Lohmoller J.-B. (1989) Latent variables path modeling with partial least squares. Heidelberg: Physica-Verlag.

Wold H. (1985) Partial Least Squares. In: Kotz, S., Johnson, N.L. (Eds.), Encyclopedia of Statistical Sciences, Vol. 6. Wiley, New York, pp. 581-591.

Wold H. (1982) Soft modeling: the basic design and some extensions. In: K.G. Joreskog & H. Wold (Eds.), Systems under indirect observations: Causality, structure, prediction, Part 2, pp. 1-54. Amsterdam: Holland.

Russolillo, G. (2012) Non-Metric Partial Least Squares. Electronic Journal of Statistics, 6, pp. 1641-1669. http://projecteuclid.org/euclid.ejs/1348665231

See Also

innerplot, outerplot,

Examples

## Not run: 
## typical example of PLS-PM in customer satisfaction analysis
## model with six LVs and reflective indicators

# load dataset satisfaction
data(satisfaction)

# path matrix
IMAG = c(0,0,0,0,0,0)
EXPE = c(1,0,0,0,0,0)
QUAL = c(0,1,0,0,0,0)
VAL = c(0,1,1,0,0,0)
SAT = c(1,1,1,1,0,0)
LOY = c(1,0,0,0,1,0)
sat_path = rbind(IMAG, EXPE, QUAL, VAL, SAT, LOY)

# plot diagram of path matrix
innerplot(sat_path)

# blocks of outer model
sat_blocks = list(1:5, 6:10, 11:15, 16:19, 20:23, 24:27)

# vector of modes (reflective indicators)
sat_mod = rep("A", 6)

# apply plspm
satpls = plspm(satisfaction, sat_path, sat_blocks, modes = sat_mod,
   scaled = FALSE)

# plot diagram of the inner model
innerplot(satpls)

# plot loadings
outerplot(satpls, what = "loadings")

# plot outer weights
outerplot(satpls, what = "weights")

## End(Not run)

Basic results for Partial Least Squares Path Modeling

Description

Estimate path models with latent variables by partial least squares approach without providing the full list of results as plspm(). This might be helpful when doing simulations, intensive computations, or when you don't want the whole enchilada.

Usage

plspm.fit(Data, path_matrix, blocks, modes = NULL,
    scaling = NULL, scheme = "centroid", scaled = TRUE,
    tol = 1e-06, maxiter = 100, plscomp = NULL)

Arguments

Data

matrix or data frame containing the manifest variables.

path_matrix

A square (lower triangular) boolean matrix representing the inner model (i.e. the path relationships betwenn latent variables).

blocks

list of vectors with column indices or column names from Data indicating the sets of manifest variables forming each block (i.e. which manifest variables correspond to each block).

scaling

optional list of string vectors indicating the type of measurement scale for each manifest variable specified in blocks. scaling must be specified when working with non-metric variables.

modes

character vector indicating the type of measurement for each block. Possible values are: "A", "B", "newA", "PLScore", "PLScow". The length of modes must be equal to the length of blocks.

scheme

string indicating the type of inner weighting scheme. Possible values are "centroid", "factorial", or "path".

scaled

whether manifest variables should be standardized. Only used when scaling = NULL. When (TRUE data is scaled to standardized values (mean=0 and variance=1). The variance is calculated dividing by N instead of N-1).

tol

decimal value indicating the tolerance criterion for the iterations (tol=0.000001). Can be specified between 0 and 0.001.

maxiter

integer indicating the maximum number of iterations (maxiter=100 by default). The minimum value of maxiter is 100.

plscomp

optional vector indicating the number of PLS components (for each block) to be used when handling non-metric data (only used if scaling is provided)

Details

plspm.fit performs the basic PLS algorithm and provides limited results (e.g. outer model, inner model, scores, and path coefficients).

The argument path_matrix is a matrix of zeros and ones that indicates the structural relationships between latent variables. path_matrix must be a lower triangular matrix; it contains a 1 when column j affects row i, 0 otherwise.

Value

An object of class "plspm".

outer_model

Results of the outer model. Includes: outer weights, standardized loadings, communalities, and redundancies

inner_model

Results of the inner (structural) model. Includes: path coeffs and R-squared for each endogenous latent variable

scores

Matrix of latent variables used to estimate the inner model. If scaled=FALSE then scores are latent variables calculated with the original data (non-stardardized). If scaled=TRUE then scores and latents have the same values

path_coefs

Matrix of path coefficients (this matrix has a similar form as path_matrix)

Author(s)

Gaston Sanchez, Giorgio Russolillo

References

Tenenhaus M., Esposito Vinzi V., Chatelin Y.M., and Lauro C. (2005) PLS path modeling. Computational Statistics & Data Analysis, 48, pp. 159-205.

Lohmoller J.-B. (1989) Latent variables path modeling with partial least squares. Heidelberg: Physica-Verlag.

Wold H. (1985) Partial Least Squares. In: Kotz, S., Johnson, N.L. (Eds.), Encyclopedia of Statistical Sciences, Vol. 6. Wiley, New York, pp. 581-591.

Wold H. (1982) Soft modeling: the basic design and some extensions. In: K.G. Joreskog & H. Wold (Eds.), Systems under indirect observations: Causality, structure, prediction, Part 2, pp. 1-54. Amsterdam: Holland.

See Also

innerplot, plot.plspm,

Examples

## Not run: 
 ## typical example of PLS-PM in customer satisfaction analysis
 ## model with six LVs and reflective indicators

 # load dataset satisfaction
 data(satisfaction)

 # inner model matrix
 IMAG = c(0,0,0,0,0,0)
 EXPE = c(1,0,0,0,0,0)
 QUAL = c(0,1,0,0,0,0)
 VAL = c(0,1,1,0,0,0)
 SAT = c(1,1,1,1,0,0)
 LOY = c(1,0,0,0,1,0)
 sat_path = rbind(IMAG, EXPE, QUAL, VAL, SAT, LOY)

 # outer model list
 sat_blocks = list(1:5, 6:10, 11:15, 16:19, 20:23, 24:27)

 # vector of reflective modes
 sat_modes = rep("A", 6)

 # apply plspm.fit
 satpls = plspm.fit(satisfaction, sat_path, sat_blocks, sat_modes,
     scaled=FALSE)

 # summary of results
 summary(satpls)

 # default plot (inner model)
 plot(satpls)
 
## End(Not run)

Two Groups Comparison in PLS-PM

Description

Performs a group comparison test for comparing path coefficients between two groups. The null and alternative hypotheses to be tested are: H0: path coefficients are not significantly different; H1: path coefficients are significantly different

Usage

plspm.groups(pls, group, Y = NULL, method = "bootstrap",
    reps = NULL)

Arguments

pls

object of class "plspm"

group

factor with 2 levels indicating the groups to be compared

Y

optional dataset (matrix or data frame) used when argument dataset=NULL inside pls.

method

method to be used in the test. Possible values are "bootstrap" or "permutation"

reps

integer indicating the number of either bootstrap resamples or number of permutations. If NULL then reps=100

Details

plspm.groups performs a two groups comparison test in PLS-PM for comparing path coefficients between two groups. Only two methods are available: 1) bootstrap, and 2) permutation. The bootstrap test is an adapted t-test based on bootstrap standard errors. The permutation test is a randomization test which provides a non-parametric option.

When the object pls does not contain a data matrix (i.e. pls$data=NULL), the user must provide the data matrix or data frame in Y.

Value

An object of class "plspm.groups"

test

Table with the results of the applied test. Includes: path coefficients of the global model, path coeffs of group1, path coeffs of group2, (absolute) difference of path coeffs between groups, and the test results with the p-value.

global

List with inner model results for the global model

group1

List with inner model results for group1

group2

List with inner model results for group2

Author(s)

Gaston Sanchez

References

Chin, W.W. (2003) A permutation procedure for multi-group comparison of PLS models. In: Vilares M., Tenenhaus M., Coelho P., Esposito Vinzi V., Morineau A. (Eds.) PLS and Related Methods - Proceedings of the International Symposium PLS03. Decisia, pp. 33-43.

Chin, W.W. (2000) Frequently Asked Questions, Partial Least Squares PLS-Graph. Available from: http://disc-nt.cba.uh.edu/chin/plsfaq/multigroup.htm

See Also

plspm

Examples

## Not run: 
 ## example with customer satisfaction analysis
 ## group comparison based on the segmentation variable "gender"

 # load data satisfaction
 data(satisfaction)

 # define inner model matrix
 IMAG = c(0,0,0,0,0,0)
 EXPE = c(1,0,0,0,0,0)
 QUAL = c(0,1,0,0,0,0)
 VAL = c(0,1,1,0,0,0)
 SAT = c(1,1,1,1,0,0)
 LOY = c(1,0,0,0,1,0)
 sat_path = rbind(IMAG, EXPE, QUAL, VAL, SAT, LOY)

 # define outer model list
 sat_blocks = list(1:5, 6:10, 11:15, 16:19, 20:23, 24:27)

 # define vector of reflective modes
 sat_mod = rep("A", 6)

 # apply plspm
 satpls = plspm(satisfaction, sat_path, sat_blocks,
                modes = sat_mod, scaled = FALSE)

 # permutation test with 100 permutations
 group_perm = plspm.groups(satpls, satisfaction$gender,
                           method="permutation", reps=100)
 group_perm
 
## End(Not run)

Quantification Plot

Description

Quantification Plots for Non-Metric PLS-PM

Usage

quantiplot(pls, lv = NULL, mv = NULL, pch = 16,
    col = "darkblue", lty = 2, ...)

Arguments

pls

a non-metric "plspm" object

lv

number or name of latent variable

mv

number or name of manifest variable

pch

Either an integer specifying a symbol or a single character to be used as the default in plotting points

col

color

lty

type of line

...

Further arguments passed on to plot.

Details

If both lv and mv are specified, only the value of lv will be taken into account.
If the given lv have more than 15 variables, only the first 15 are plotted.


Response Based Unit Segmentation (REBUS)

Description

Performs all the steps of the REBUS-PLS algorithm. Starting from the global model, REBUS allows us to detect local models with better performance.

Usage

rebus.pls(pls, Y = NULL, stop.crit = 0.005,
    iter.max = 100)

Arguments

pls

Object of class "plspm"

Y

Optional dataset (matrix or data frame) used when argument dataset=NULL inside pls.

stop.crit

Number indicating the stop criterion for the iterative algorithm. Use a threshold of less than 0.05% of units changing class from one iteration to the other as stopping rule.

iter.max

integer indicating the maximum number of iterations.

Value

An object of class "rebus", basically a list with:

loadings

Matrix of standardized loadings (i.e. correlations with LVs.) for each local model.

path.coefs

Matrix of path coefficients for each local model.

quality

Matrix containing the average communalities, average redundancies, R2 values, and GoF values for each local model.

segments

Vector defining for each unit the class membership.

origdata.clas

The numeric matrix with original data and with a new column defining class membership of each unit.

Author(s)

Laura Trinchera, Gaston Sanchez

References

Esposito Vinzi V., Trinchera L., Squillacciotti S., and Tenenhaus M. (2008) REBUS-PLS: A Response-Based Procedure for detecting Unit Segments in PLS Path Modeling. Applied Stochastic Models in Business and Industry (ASMBI), 24, pp. 439-458.

Trinchera, L. (2007) Unobserved Heterogeneity in Structural Equation Models: a new approach to latent class detection in PLS Path Modeling. Ph.D. Thesis, University of Naples "Federico II", Naples, Italy.

http://www.fedoa.unina.it/2702/1/Trinchera_Statistica.pdf

See Also

plspm, res.clus, it.reb, rebus.test, local.models

Examples

## Not run: 
 ## typical example of PLS-PM in customer satisfaction analysis
 ## model with six LVs and reflective indicators
 ## example of rebus analysis with simulated data

 # load data
 data(simdata)

 # Calculate plspm
 sim_inner = matrix(c(0,0,0,0,0,0,1,1,0), 3, 3, byrow=TRUE)
 dimnames(sim_inner) = list(c("Price", "Quality", "Satisfaction"),
                            c("Price", "Quality", "Satisfaction"))
 sim_outer = list(c(1,2,3,4,5), c(6,7,8,9,10), c(11,12,13))
 sim_mod = c("A", "A", "A")  # reflective indicators
 sim_global = plspm(simdata, sim_inner,
                    sim_outer, modes=sim_mod)
 sim_global

 # run rebus.pls and choose the number of classes
 # to be taken into account according to the displayed dendrogram.
 rebus_sim = rebus.pls(sim_global, stop.crit = 0.005, iter.max = 100)

 # You can also compute complete outputs for local models by running:
 local_rebus = local.models(sim_global, rebus_sim)
 
## End(Not run)

Permutation Test for REBUS Multi-Group Comparison

Description

Performs permutation tests for comparing pairs of groups from a REBUS object.

Usage

rebus.test(pls, reb, Y = NULL)

Arguments

pls

Object of class "plspm" returned by plspm

reb

Object of class "rebus" returned by either rebus.pls or it.reb.

Y

Optional dataset (matrix or data frame) used when argument dataset=NULL inside pls.

Details

A permutation test on path coefficients, loadings, and GoF index is applied to the classes obtained from REBUS, by comparing two classes at a time. That is to say, a permutation test is applied on pair of classes. The number of permutations in each test is 100. In turn, the number of classes handled by rebus.test is limited to 6.

When pls$data=NULL (there is no data matrix), the user must provide the data matrix or data frame in Y.

Value

An object of class "rebus.test", basically a list containing the results of each pair of compared classes. In turn, each element of the list is also a list with the results for the path coefficients, loadings, and GoF index.

Author(s)

Laura Trinchera, Gaston Sanchez

References

Chin, W.W. (2003) A permutation procedure for multi-group comparison of PLS models. In: Vilares M., Tenenhaus M., Coelho P., Esposito Vinzi V., Morineau A. (Eds.) PLS and Related Methods - Proceedings of the International Symposium PLS03. Decisia, pp. 33-43.

See Also

rebus.pls, local.models

Examples

## Not run: 
 ## typical example of PLS-PM in customer satisfaction analysis
 ## model with six LVs and reflective indicators
 ## example of rebus analysis with simulated data

 # load data
 data(simdata)

 # Calculate plspm
 sim_path = matrix(c(0,0,0,0,0,0,1,1,0), 3, 3, byrow=TRUE)
 dimnames(sim_path) = list(c("Price", "Quality", "Satisfaction"),
                            c("Price", "Quality", "Satisfaction"))
 sim_blocks = list(c(1,2,3,4,5), c(6,7,8,9,10), c(11,12,13))
 sim_mod = c("A", "A", "A")  # reflective indicators
 sim_global = plspm(simdata, sim_path,
                    sim_blocks, modes=sim_mod)
 sim_global

 # Cluster analysis on residuals of global model
 sim_clus = res.clus(sim_global)

 # Iterative steps of REBUS algorithm on 2 classes
 rebus_sim = it.reb(sim_global, sim_clus, nk=2,
                    stop.crit=0.005, iter.max=100)

 # apply rebus.test
 sim_permu = rebus.test(sim_global, rebus_sim)

 # inspect sim.rebus
 sim_permu
 sim_permu$test_1_2

 # or equivalently
 sim_permu[[1]]
 
## End(Not run)

Clustering on communality and structural residuals

Description

Computes communality and structural residuals from a global PLS-PM model and performs a Hierarchical Cluster Analysis on these residuals according to the REBUS algorithm.

Usage

res.clus(pls, Y = NULL)

Arguments

pls

Object of class "plspm"

Y

Optional dataset (matrix or data frame) used when argument dataset=NULL inside pls.

Details

res.clus() comprises the second and third steps of the REBUS-PLS Algorithm. It computes communality and structural residuals. Then it performs a Hierarchical Cluster Analysis on these residuals (step three of REBUS-PLS Algorithm). As a result, this function directly provides a dendrogram obtained from a Hierarchical Cluster Analysis.

Value

An Object of class "hclust" containing the results of the Hierarchical Cluster Analysis on the communality and structural residuals.

Author(s)

Laura Trinchera, Gaston Sanchez

References

Esposito Vinzi V., Trinchera L., Squillacciotti S., and Tenenhaus M. (2008) REBUS-PLS: A Response-Based Procedure for detecting Unit Segments in PLS Path Modeling. Applied Stochastic Models in Business and Industry (ASMBI), 24, pp. 439-458.

Trinchera, L. (2007) Unobserved Heterogeneity in Structural Equation Models: a new approach to latent class detection in PLS Path Modeling. Ph.D. Thesis, University of Naples "Federico II", Naples, Italy.

See Also

it.reb, plspm

Examples

## Not run: 
 ## example of rebus analysis with simulated data

 # load data
 data(simdata)

 # Calculate plspm
 sim_path = matrix(c(0,0,0,0,0,0,1,1,0), 3, 3, byrow=TRUE)
 dimnames(sim_path) = list(c("Price", "Quality", "Satisfaction"),
                            c("Price", "Quality", "Satisfaction"))
 sim_blocks = list(c(1,2,3,4,5), c(6,7,8,9,10), c(11,12,13))
 sim_modes = c("A", "A", "A")
 sim_global = plspm(simdata, sim_path,
                    sim_blocks, modes=sim_modes)
 sim_global

 # Then compute cluster analysis on the residuals of global model
 sim_clus = res.clus(sim_global)
 
## End(Not run)

Rescale Latent Variable Scores

Description

Rescale standardized latent variable scores to original scale of manifest variables

Usage

rescale(pls, data = NULL)

Arguments

pls

object of class "plspm"

data

Optional dataset (matrix or data frame) used when argument dataset=NULL inside pls.

Details

rescale requires all outer weights to be positive

Value

A data frame with the rescaled latent variable scores

Author(s)

Gaston Sanchez

See Also

plspm

Examples

## Not run: 
 ## example with customer satisfaction analysis

 # load data satisfaction
 data(satisfaction)

 # define inner model matrix
 IMAG = c(0,0,0,0,0,0)
 EXPE = c(1,0,0,0,0,0)
 QUAL = c(0,1,0,0,0,0)
 VAL = c(0,1,1,0,0,0)
 SAT = c(1,1,1,1,0,0)
 LOY = c(1,0,0,0,1,0)
 sat_path = rbind(IMAG, EXPE, QUAL, VAL, SAT, LOY)

 # define outer model list
 sat_blocks = list(1:5, 6:10, 11:15, 16:19, 20:23, 24:27)

 # define vector of reflective modes
 sat_modes = rep("A", 6)

 # apply plspm
 my_pls = plspm(satisfaction, sat_path, sat_blocks, modes = sat_modes,
              scaled=FALSE)

 # rescaling standardized scores of latent variables
 new_scores = rescale(my_pls)

 # compare standardized LVs against rescaled LVs
 summary(my_pls$scores)
 summary(new_scores)
 
## End(Not run)

Dillon-Goldstein's rho

Description

Dillon-Goldstein's rho of a single block of variables

Usage

rho(X)

Arguments

X

matrix representing one block of manifest variables

Value

Dillon-Goldstein's rho

Author(s)

Gaston Sanchez

See Also

alpha, unidim

Examples

## Not run: 
 # load dataset satisfaction
 data(satisfaction)

 # block Image (first 5 columns of satisfaction)
 Image = satisfaction[,1:5]

 # compute Dillon-Goldstein's rho for Image block
 rho(Image)
 
## End(Not run)

Russett A

Description

Russett dataset with variable demo as numeric variable

Format

A data frame with 47 rows and 9 columns


Russett B

Description

Russett dataset with variable demo as factor

Format

A data frame with 47 rows and 9 columns


Russett dataset

Description

Data set from Russett (1964) about agricultural inequality, industrial development and political instability.

Usage

data(russett)

Format

A data frame with 47 observations on the following 11 variables. The variables may be used to construct three latent concepts: 1) AGRIN=Agricultural Inequality, 2) INDEV=Industrial Development, 3) POLINS=Political Instability.

Num Variable Description Concept
1 gini Inequality of land distribution AGRIN
2 farm Percentage of farmers that own half of the land AGRIN
3 rent Percentage of farmers that rent all their land AGRIN
4 gnpr Gross national product per capita INDEV
5 labo Percentage of labor force employed in agriculture INDEV
6 inst Instability of executive (1945-1961) POLINS
7 ecks Number of violent internal war incidents (1941-1961) POLINS
8 death Number of people killed as a result of civic group violence (1950-1962) POLINS
9 demostab Political regime: stable democracy POLINS
10 demoinst Political regime: unstable democracy POLINS
11 dictator Political regime: dictatorship POLINS

References

Russett B.M. (1964) Inequality and Instability: The Relation of Land Tenure to Politics. World Politics 16:3, pp. 442-454.

Examples

data(russett)
  russett

Satisfaction dataset

Description

This data set contains the variables from a customer satisfaction study of a Spanish credit institution on 250 customers.

Usage

satisfaction

Format

A data frame with 250 observations and 28 variables. Variables from 1 to 27 refer to six latent concepts: 1) IMAG=Image, 2) EXPE=Expectations, 3) QUAL=Quality, 4) VAL=Value, 5) SAT=Satisfaction, and 6) LOY=Loyalty. The last variable is a categorical variable indicating the gender of the individual.

IMAG: Includes variables such as reputation, trustworthiness, seriousness, solidness, and caring about customer's needs.
EXPE: Includes variables such as products and services provided, customer service, providing solutions, and expectations for the overall quality.
QUAL: Includes variables such as reliable products and services, range of products and services, personal advice, and overall perceived quality.
VAL: Includes variables such as beneficial services and products, valuable investments, quality relative to price, and price relative to quality.
SAT: Includes variables such as overall rating of satisfaction, fulfillment of expectations, satisfaction relative to other banks, and performance relative to customer's ideal bank.
LOY: Includes variables such as propensity to choose the same bank again, propensity to switch to other bank, intention to recommend the bank to friends, and sense of loyalty.

Source

Laboratory of Information Analysis and Modeling (LIAM). Facultat d'Informatica de Barcelona, Universitat Politecnica de Catalunya.

Examples

data(satisfaction)
  satisfaction

Simulated data for REBUS with two groups

Description

Simulated data with two latent classes showing different local models.

Usage

data(simdata)

Format

A data frame of simulated data with 400 observations on the following 14 variables.

mv1

first manifest variable of the block Price Fairness

mv2

second manifest variable of the block Price Fairness

mv3

third manifest variable of the block Price Fairness

mv4

fourth manifest variable of the block Price Fairness

mv5

fifth manifest variable of the block Price Fairness

mv6

first manifest variable of the block Quality

mv7

second manifest variable of the block Quality

mv8

third manifest variable of the block Quality

mv9

fourth manifest variable of the block Quality

mv10

fifth manifest variable of the block Quality

mv11

first manifest variable of the block Customer Satisfaction

mv12

second manifest variable of the block Customer Satisfaction

mv13

third manifest variable of the block Customer Satisfaction

group

a numeric vector

Details

The postulated model overlaps the one used by Jedidi et al. (1997) and by Esposito Vinzi et al. (2007) for their numerical examples. It is composed of one latent endogenous variable, Customer Satisfaction, and two latent exogenous variables, Price Fairness and Quality. Each latent exogenous variable (Price Fairness and Quality) has five manifest variables (reflective mode), and the latent endogenous variable (Customer Satisfaction) is measured by three indicators (reflective mode).

Two latent classes showing different local models are supposed to exist. Each one is composed of 200 units. Thus, the data on the aggregate level for each one of the numerical examples includes 400 units.

The simulation scheme involves working with local models that are different at both the measurement and the structural model levels. In particular, the experimental sets of data consist of two latent classes with the following characteristics:
(a) Class 1 - price fairness seeking customers - characterized by a strong relationship between Price Fairness and Customer Satisfaction (close to 0.9) and a weak relationship between Quality and Customer Satisfaction (close to 0.1), as well as by a weak correlation between the 3rd manifest variable of the Price Fairness block (mv3) and the corresponding latent variable;
(b) Class 2 - quality oriented customers - characterized by a strong relationship between Quality and Customer Satisfaction (close to 0.1) and a weak relationship between Price Fairness and Customer Satisfaction (close to 0.9), as well as by a weak correlation between the 3rd manifest variable (mv8) of the Quality block and the corresponding latent variable.

Source

Simulated data from Trinchera (2007). See References below.

References

Esposito Vinzi, V., Ringle, C., Squillacciotti, S. and Trinchera, L. (2007) Capturing and treating unobserved heterogeneity by response based segmentation in PLS path modeling. A comparison of alternative methods by computational experiments. Working paper, ESSEC Business School.

Jedidi, K., Jagpal, S. and De Sarbo, W. (1997) STEMM: A general finite mixture structural equation model. Journal of Classification 14, pp. 23-50.

Trinchera, L. (2007) Unobserved Heterogeneity in Structural Equation Models: a new approach to latent class detection in PLS Path Modeling. Ph.D. Thesis, University of Naples "Federico II", Naples, Italy.

Examples

data(simdata)
simdata

Spanish football dataset

Description

This data set contains the results of the teams in the Spanish football league 2008-2009.

Usage

spainfoot

Format

A data frame with 20 observations on 14 variables. The variables may be used to construct four latent concepts: 1) ATTACK=Attack, 2) DEFENSE=Defense, 3) SUCCESS=Success, 4) INDIS=Indiscipline.

Num Variable Description Concept
1 GSH Goals Scored Home: total number of goals scored at home ATTACK
2 GSA Goals Scored Away: total number of goals scored away ATTACK
3 SSH Success to Score Home: Percentage of matches with scores goals at home ATTACK
4 SSA Success to Score Away: Percentage of matches with scores goals away ATTACK
5 GCH Goals Conceded Home: total number of goals conceded at home DEFENSE
6 GCA Goals Conceded Away: total number of goals conceded away DEFENSE
7 CSH Clean Sheets Home: percentage of matches with no conceded goals at home DEFENSE
8 CSA Clean Sheets Away: percentage of matches with no conceded goals away DEFENSE
9 WMH Won Matches Home: total number of won matches at home SUCCESS
10 WMA Won matches Away: total number of won matches away SUCCESS
11 LWR Longest Winning Run: longest run of won matches SUCCESS
12 LRWR Longest Run Without Loss: longest run of matches without losing SUCCESS
13 YC Yellow Cards: total number of yellow cards INDIS
14 RC Red Cards: total number of red cards INDIS

Source

League Day. http://www.leagueday.com
Statto. http://www.statto.com
BDFutbol. http://www.statto.com
Cero a cero. http://www.ceroacero.es/

Examples

data(spainfoot)
  spainfoot

Technology data set

Description

This data set contains the variables from a "user and acceptance of technology" model on 300 users.

Usage

data(technology)

Format

A data frame with 300 observations and 21 variables. Variables can be grouped in six latent concepts: 1) PERF_EXP=Performance Expectancy, 2) EFF_EXP=Effort Expectancy, 3) SUB_NORM=Subjective Norm, 4) FAC_COND=Facilitating Conditions, 5) BEH_INT=Behavioral Intention, and 6) USE_BEH=Use Behavior.

Num Variable Description
1 pe1 I find computers useful in my job
2 pe2 Using computers in my job enables me to accomplish tasks more quickly
3 pe3 Using computers in my job increases my productivity
4 pe4 Using computers enhances my effectiveness on the job
5 ee1 My interactions with computers are clear and understandable
6 ee2 It is easy for me to become skillful using computers
7 ee3 I find computers easy to use
8 ee4 Learning to use computers is easy for me
9 sn1 Most people who are important to me think I should use computers
10 sn2 Most people who are important to me would want me to use computers
11 sn3 People whose opinions I value would prefer me to use computers
12 fc1 I have the resources and the knowledge and the ability to make use of the computer
13 fc1 A central support was available to help with computer problems
14 fc1 Management provided most of the necessary help and resources for computing
15 bi1 I predict I will continue to use computers on a regular basis
16 bi2 What are the chances in 100 that you will continue as a computer user?
17 bi3 To do my work, I would use computers rather than any other means available
18 use1 On an average working day, how much time do you spend using computers?
19 use2 On average, how frequently do you use computers?
20 use3 How many different computer applications have you worked with or used in your job?
21 use4 According to your job requirements, indicate each task you use computers to perform?

References

Venkatesh V., Morris M.G., Davis G.B., Davis F.D. (2003) User Acceptance of Information Technology: Toward a Unified View. MIS Quarterly, Vol. 27 (3): 425-478.

Examples

data(technology)
  summary(technology)

Unidimensionality of blocks

Description

Compute unidimensionality indices (a.k.a. Composite Reliability indices)

Usage

unidim(Data, blocks = NULL)

Arguments

Data

matrix or data frame with variables

blocks

optional list with vectors indicating the variables in each block

Value

A data frame with the following columns:

Block

name of block

MVs

number of manifest variables in each block

C.alpha

Cronbach's alpha

DG.rho

Dillon-Goldstein rho

eig.1st

First eigenvalue

eig.2nd

Second eigenvalue

Author(s)

Gaston Sanchez

See Also

alpha, rho

Examples

## Not run: 
 # load dataset satisfaction
 data(satisfaction)

 # blocks Image and Expectations
 ima_expe = list(Image=1:5, Expec=6:10)

 # compute unidimensionality indices
 unidim(satisfaction, ima_expe)
 
## End(Not run)

Wines dataset

Description

These data are the results of a chemical analysis of wines grown in the same region in Italy but derived from three different cultivars. The analysis determined the quantities of 13 constituents found in each of the three types of wines.

Usage

wines

Format

A data frame with 178 observations and 14 variables.

Num Variable Description
1 class Type of wine
2 alcohol Alcohol
3 malic.acid Malic acid
4 ash Ash
5 alcalinity Alcalinity
6 magnesium Magnesium
7 phenols Total phenols
8 flavanoids Flavanoids
9 nofla.phen Nonflavanoid phenols
10 proantho Proanthocyanins
11 col.intens Color intensity
12 hue Hue
13 diluted OD280/OD315 of diluted wines
14 proline Proline

Source

Machine Learning Repository. http://archive.ics.uci.edu/ml/datasets/Wine

References

Forina, M. et al, PARVUS An Extendible Package for Data Exploration, Classification and Correlation. Institute of Pharmaceutical and Food Analysis and Technologies, Via Brigata Salerno, 16147 Genoa, Italy.

Examples

data(wines)
  wines