Bechtoldt               Seven data sets showing a bifactor solution.
Dwyer                   8 cognitive variables used by Dwyer for an
                        example.
Gleser                  Example data from Gleser, Cronbach and
                        Rajaratnam (1965) to show basic principles of
                        generalizability theory.
Gorsuch                 Example data set from Gorsuch (1997) for an
                        example factor extension.
Harman                  Five data sets from Harman (1967). 9 cognitive
                        variables from Holzinger and 8 emotional
                        variables from Burt
ICC                     Intraclass Correlations (ICC1, ICC2, ICC3 from
                        Shrout and Fleiss)
ICLUST.cluster          Function to form hierarchical cluster analysis
                        of items
ICLUST.graph            create control code for ICLUST graphical output
ICLUST.rgraph           Draw an ICLUST graph using the Rgraphviz
                        package
ICLUST.sort             Sort items by absolute size of cluster loadings
KMO                     Find the Kaiser, Meyer, Olkin Measure of
                        Sampling Adequacy
Promax                  Perform bifactor, promax or targeted rotations
                        and return the inter factor angles.
SD                      Find the Standard deviation for a vector,
                        matrix, or data.frame - do not return error if
                        there are no cases
Schmid                  12 variables created by Schmid and Leiman to
                        show the Schmid-Leiman Transformation
Schutz                  The Schutz correlation matrix example from
                        Shapiro and ten Berge
Tucker                  9 Cognitive variables discussed by Tucker and
                        Lewis (1973)
VSS                     Apply the Very Simple Structure, MAP, and other
                        criteria to determine the appropriate number of
                        factors.
VSS.parallel            Compare real and random VSS solutions
VSS.plot                Plot VSS fits
VSS.scree               Plot the successive eigen values for a scree
                        test
Yule                    From a two by two table, find the Yule
                        coefficients of association, convert to phi, or
                        tetrachoric, recreate table the table to create
                        the Yule coefficient.
ability                 16 ability items scored as correct or
                        incorrect.
affect                  Two data sets of affect and arousal scores as a
                        function of personality and movie conditions
alpha                   Find two estimates of reliability: Cronbach's
                        alpha and Guttman's Lambda 6.
bestScales              A set of functions for factorial and empirical
                        scale construction
bfi                     25 Personality items representing 5 factors
bi.bars                 Draw pairs of bargraphs based on two groups
biplot.psych            Draw biplots of factor or component scores by
                        factor or component loadings
blant                   A 29 x 29 matrix that produces weird factor
                        analytic results
block.random            Create a block randomized structure for n
                        independent variables
blot                    Bond's Logical Operations Test - BLOT
bock                    Bock and Liberman (1970) data set of 1000
                        observations of the LSAT
burt                    11 emotional variables from Burt (1915)
cattell                 12 cognitive variables from Cattell (1963)
circ.tests              Apply four tests of circumplex versus simple
                        structure
cities                  Distances between 11 US cities
cluster.fit             cluster Fit: fit of the cluster model to a
                        correlation matrix
cluster.loadings        Find item by cluster correlations, corrected
                        for overlap and reliability
cluster.plot            Plot factor/cluster loadings and assign items
                        to clusters by their highest loading.
cluster2keys            Convert a cluster vector (from e.g., kmeans) to
                        a keys matrix suitable for scoring item
                        clusters.
cohen.d                 Find Cohen d and confidence intervals
cohen.kappa             Find Cohen's kappa and weighted kappa
                        coefficients for correlation of two raters
comorbidity             Convert base rates of two diagnoses and their
                        comorbidity into phi, Yule, and tetrachorics
cor.ci                  Bootstrapped confidence intervals for raw and
                        composite correlations
cor.plot                Create an image plot for a correlation or
                        factor matrix
cor.smooth              Smooth a non-positive definite correlation
                        matrix to make it positive definite
cor.wt                  The sample size weighted correlation may be
                        used in correlating aggregated data
cor2dist                Convert correlations to distances (necessary to
                        do multidimensional scaling of correlation
                        data)
corFiml                 Find a Full Information Maximum Likelihood
                        (FIML) correlation or covariance matrix from a
                        data matrix with missing data
corr.test               Find the correlations, sample sizes, and
                        probability values between elements of a matrix
                        or data.frame.
correct.cor             Find dis-attenuated correlations given
                        correlations and reliabilities
cortest.bartlett        Bartlett's test that a correlation matrix is an
                        identity matrix
cortest.mat             Chi square tests of whether a single matrix is
                        an identity matrix, or a pair of matrices are
                        equal.
cosinor                 Functions for analysis of circadian or diurnal
                        data
count.pairwise          Count number of pairwise cases for a data set
                        with missing (NA) data.
cta                     Simulate the C(ues) T(endency) A(ction) model
                        of motivation
cubits                  Galton's example of the relationship between
                        height and 'cubit' or forearm length
cushny                  A data set from Cushny and Peebles (1905) on
                        the effect of three drugs on hours of sleep,
                        used by Student (1908)
densityBy               Create a 'violin plot' or density plot of the
                        distribution of a set of variables
describe                Basic descriptive statistics useful for
                        psychometrics
describeBy              Basic summary statistics by group
df2latex                Convert a data frame, correlation matrix, or
                        factor analysis output to a LaTeX table
dfOrder                 Sort (order) a dataframe or matrix by multiple
                        columns
diagram                 Helper functions for drawing path model
                        diagrams
draw.tetra              Draw a correlation ellipse and two normal
                        curves to demonstrate tetrachoric correlation
dummy.code              Create dummy coded variables
eigen.loadings          Convert eigen vectors and eigen values to the
                        more normal (for psychologists) component
                        loadings
ellipses                Plot data and 1 and 2 sigma correlation
                        ellipses
epi                     Eysenck Personality Inventory (EPI) data for
                        3570 participants
epi.bfi                 13 personality scales from the Eysenck
                        Personality Inventory and Big 5 inventory
error.bars              Plot means and confidence intervals
error.bars.by           Plot means and confidence intervals for
                        multiple groups
error.crosses           Plot x and y error bars
error.dots              Show a dot.chart with error bars for different
                        groups or variables
errorCircles            Two way plots of means, error bars, and sample
                        sizes
esem                    Perform and Exploratory Structural Equation
                        Model (ESEM) by using factor extension
                        techniques
fa                      Exploratory Factor analysis using MinRes
                        (minimum residual) as well as EFA by Principal
                        Axis, Weighted Least Squares or Maximum
                        Likelihood
fa.diagram              Graph factor loading matrices
fa.extension            Apply Dwyer's factor extension to find factor
                        loadings for extended variables
fa.multi                Multi level (hierarchical) factor analysis
fa.parallel             Scree plots of data or correlation matrix
                        compared to random "parallel" matrices
fa.poly                 Deprecated Exploratory Factor analysis
                        functions.  Please use fa
fa.random               A first approximation to Random Effects
                        Exploratory Factor Analysis
fa.sort                 Sort factor analysis or principal components
                        analysis loadings
factor.congruence       Coefficient of factor congruence
factor.fit              How well does the factor model fit a
                        correlation matrix. Part of the VSS package
factor.model            Find R = F F' + U2 is the basic factor model
factor.residuals        R* = R- F F'
factor.rotate           "Hand" rotate a factor loading matrix
factor.scores           Various ways to estimate factor scores for the
                        factor analysis model
factor.stats            Find various goodness of fit statistics for
                        factor analysis and principal components
factor2cluster          Extract cluster definitions from factor
                        loadings
fisherz                 Transformations of r, d, and t including Fisher
                        r to z and z to r and confidence intervals
galton                  Galton's Mid parent child height data
geometric.mean          Find the geometric mean of a vector or columns
                        of a data.frame.
glb.algebraic           Find the greatest lower bound to reliability.
harmonic.mean           Find the harmonic mean of a vector, matrix, or
                        columns of a data.frame
headTail                Combine calls to head and tail
heights                 A data.frame of the Galton (1888) height and
                        cubit data set.
iclust                  iclust: Item Cluster Analysis - Hierarchical
                        cluster analysis using psychometric principles
iclust.diagram          Draw an ICLUST hierarchical cluster structure
                        diagram
income                  US family income from US census 2008
interp.median           Find the interpolated sample median, quartiles,
                        or specific quantiles for a vector, matrix, or
                        data frame
iqitems                 16 multiple choice IQ items
irt.1p                  Item Response Theory estimate of theta
                        (ability) using a Rasch (like) model
irt.fa                  Item Response Analysis by Exploratory Factor
                        Analysis of tetrachoric/polychoric correlations
irt.item.diff.rasch     Simple function to estimate item difficulties
                        using IRT concepts
irt.responses           Plot probability of multiple choice responses
                        as a function of a latent trait
kaiser                  Apply the Kaiser normalization when rotating
                        factors
logistic                Logistic transform from x to p and logit
                        transform from p to x
lowerUpper              Combine two square matrices to have a lower off
                        diagonal for one, upper off diagonal for the
                        other
make.keys               Create a keys matrix for use by score.items or
                        cluster.cor
mardia                  Calculate univariate or multivariate (Mardia's
                        test) skew and kurtosis for a vector, matrix,
                        or data.frame
mat.sort                Sort the elements of a correlation matrix to
                        reflect factor loadings
matrix.addition         A function to add two vectors or matrices
mediate                 Estimate and display direct and indirect
                        effects of mediators and moderator in path
                        models
mixedCor                Find correlations for mixtures of continuous,
                        polytomous, and dichotomous variables
msq                     75 mood items from the Motivational State
                        Questionnaire for 3896 participants
mssd                    Find von Neuman's Mean Square of Successive
                        Differences
multi.hist              Multiple histograms with density and normal
                        fits on one page
multilevel.reliability
                        Find and plot various
                        reliability/gneralizability coefficients for
                        multilevel data
neo                     NEO correlation matrix from the NEO_PI_R manual
omega                   Calculate McDonald's omega estimates of general
                        and total factor saturation
omega.graph             Graph hierarchical factor structures
outlier                 Find and graph Mahalanobis squared distances to
                        detect outliers
p.rep                   Find the probability of replication for an F,
                        t, or r and estimate effect size
paired.r                Test the difference between (un)paired
                        correlations
pairs.panels            SPLOM, histograms and correlations for a data
                        matrix
parcels                 Find miniscales (parcels) of size 2 or 3 from a
                        set of items
partial.r               Find the partial correlations for a set (x) of
                        variables with set (y) removed.
peas                    Galton's Peas
phi                     Find the phi coefficient of correlation between
                        two dichotomous variables
phi.demo                A simple demonstration of the Pearson, phi, and
                        polychoric corelation
phi2tetra               Convert a phi coefficient to a tetrachoric
                        correlation
plot.psych              Plotting functions for the psych package of
                        class "psych"
polar                   Convert Cartesian factor loadings into polar
                        coordinates
polychor.matrix         Phi or Yule coefficient matrix to polychoric
                        coefficient matrix
predict.psych           Prediction function for factor analysis or
                        principal components
principal               Principal components analysis (PCA)
print.psych             Print and summary functions for the psych class
psych                   A package for personality, psychometric, and
                        psychological research
psych.misc              Miscellaneous helper functions for the psych
                        package
r.test                  Tests of significance for correlations
rangeCorrection         Correct correlations for restriction of range.
                        (Thorndike Case 2)
read.file               Shortcuts for reading from the clipboard or a
                        file
rescale                 Function to convert scores to "conventional "
                        metrics
residuals.psych         Extract residuals from various psych objects
reverse.code            Reverse the coding of selected items prior to
                        scale analysis
sat.act                 3 Measures of ability: SATV, SATQ, ACT
scaling.fits            Test the adequacy of simple choice, logistic,
                        or Thurstonian scaling.
scatterHist             Draw a scatter plot with associated X and Y
                        histograms, densities and correlation
schmid                  Apply the Schmid Leiman transformation to a
                        correlation matrix
score.alpha             Score scales and find Cronbach's alpha as well
                        as associated statistics
score.multiple.choice   Score multiple choice items and provide basic
                        test statistics
scoreIrt                Find Item Response Theory (IRT) based scores
                        for dichotomous or polytomous items
scoreItems              Score item composite scales and find Cronbach's
                        alpha, Guttman lambda 6 and item whole
                        correlations
scoreOverlap            Find correlations of composite variables
                        (corrected for overlap) from a larger matrix.
scrub                   A utility for basic data cleaning and recoding.
                        Changes values outside of minimum and maximum
                        limits to NA.
setCor                  Set Correlation and Multiple Regression from
                        matrix or raw input
sim                     Functions to simulate
                        psychological/psychometric data.
sim.VSS                 create VSS like data
sim.anova               Simulate a 3 way balanced ANOVA or linear
                        model, with or without repeated measures.
sim.congeneric          Simulate a congeneric data set
sim.hierarchical        Create a population or sample correlation
                        matrix, perhaps with hierarchical structure.
sim.item                Generate simulated data structures for
                        circumplex, spherical, or simple structure
sim.multilevel          Simulate multilevel data with specified within
                        group and between group correlations
sim.structure           Create correlation matrices or data matrices
                        with a particular measurement and structural
                        model
simulation.circ         Simulations of circumplex and simple structure
smc                     Find the Squared Multiple Correlation (SMC) of
                        each variable with the remaining variables in a
                        matrix
spi                     A sample from the SAPA Personality Inventory
                        including an item dictionary and scoring keys.
spider                  Make "radar" or "spider" plots.
splitHalf               Alternative estimates of test reliabiity
statsBy                 Find statistics (including correlations) within
                        and between groups for basic multilevel
                        analyses
structure.diagram       Draw a structural equation model specified by
                        two measurement models and a structural model
structure.list          Create factor model matrices from an input list
superMatrix             Form a super matrix from two sub matrices.
table2matrix            Convert a table with counts to a matrix or
                        data.frame representing those counts.
test.irt                A simple demonstration (and test) of various
                        IRT scoring algorthims.
test.psych              Testing of functions in the psych package
tetrachoric             Tetrachoric, polychoric, biserial and
                        polyserial correlations from various types of
                        input
thurstone               Thurstone Case V scaling
tr                      Find the trace of a square matrix
unidim                  Several indices of the unidimensionality of a
                        set of variables.
vegetables              Paired comparison of preferences for 9
                        vegetables
winsor                  Find the Winsorized scores, means, sds or
                        variances for a vector, matrix, or data.frame
withinBetween           An example of the distinction between within
                        group and between group correlations
