Harman                  Two 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                  ICLUST: Item Cluster Analysis -- Hierarchical
                        cluster analysis using psychometric principles
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
Promax                  Perform 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
Tucker                  9 Cognitive variables discussed by Tucker and
                        Lewis (1973)
VSS                     Apply the Very Simple Structure and MAP
                        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
                        polychoric, recreate table the table to create
                        the Yule coefficient.
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.
bfi                     25 Personality items representing 5 factors
bifactor                Seven data sets showing a bifactor solution.
circ.tests              Apply four tests of circumplex versus simple
                        structure
cities                  Distances between 11 US cities
cluster.cor             Find correlations of composite variables from a
                        larger matrix
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.
comorbidity             Convert base rates of two diagnoses and their
                        comorbidity into phi, Yule, and tetrachorics
cor.plot                Create an image plot for a correlation or
                        factor matrix
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
describe                Basic descriptive statistics useful for
                        psychometrics
describe.by             Basic summary statistics by group
diagram                 Helper functions for drawing path model
                        diagrams
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.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
fa                      Factor analysis by Principal Axis, MinRes
                        (minimum residual), Weighted Least Squares or
                        Maximum Likelihood
fa.diagram              Graph factor loading matrices
fa.parallel             Scree plots of data or correlation matrix
                        compared to random "parallel" matrices
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.stats            Find various goodness of fit statistics for
                        factor analysis and principal components
factor2cluster          Extract cluster definitions from factor
                        loadings
fisherz                 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.
guttman                 Alternative estimates of test reliabiity
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.diagram          Draw an ICLUST hierarchical cluster structure
                        diagram
interp.median           Find the interpolated sample median, quartiles,
                        or specific quantiles for a vector, matrix, or
                        data frame
iqitems                 14 multiple choice IQ items
irt.1p                  Item Response Theory estimate of theta
                        (ability) using a Rasch (like) model
irt.item.diff.rasch     Simple function to estimate item difficulties
                        using IRT concepts
make.keys               Create a keys matrix for use by score.items or
                        cluster.cor
mat.regress             Multiple Regression from matrix input
mat.sort                Sort the elements of a correlation matrix to
                        reflect factor loadings
matrix.addition         A function to add two vectors or matrices
msq                     75 mood items from the Motivational State
                        Questionnaire for 3896 participants
multi.hist              Multiple histograms with density and normal
                        fits on one page
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
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
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
phi2poly                Convert a phi coefficient to a polychoric
                        correlation
plot.psych              Plotting functions for the psych package of
                        class "psych"
polar                   Convert Cartesian factor loadings into polar
                        coordinates
poly.mat                Find polychoric correlations of item data
polychor.matrix         Phi or Yule coefficient matrix to polychoric
                        coefficient matrix
principal               Principal components analysis
print.psych             Print and summary functions for the psych class
psych                   A package for personality, psychometric, and
                        psychological research
r.test                  Tests of significance for correlations
read.clipboard          shortcut for reading from the clipboard
rescale                 Function to convert scores to "conventional "
                        metrics
sat.act                 3 Measures of ability: SATV, SATQ, ACT
scaling.fits            Test the adequacy of simple choice, logistic,
                        or Thurstonian scaling.
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.items             Score item composite scales and find Cronbach's
                        alpha, Guttman lambda 6 and item whole
                        correlations
score.multiple.choice   Score multiple choice items and provide basic
                        test statistics
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 or simple structure
sim.structure           Create correlation matrices or data matrices
                        with a particular measurement and structural
                        model
simulation.circ         Simulations of circumplex and simple structure
skew                    Calculate skew or kurtosis for a vector,
                        matrix, or data.frame
smc                     Find the Squared Multiple Correlation (SMC) of
                        each variable with the remaining variables in a
                        matrix
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
super.matrix            Form a super matrix from two sub matrices.
table2matrix            Convert a table with counts to a matrix or
                        data.frame representing those counts.
test.psych              Testing of functions in the psych package
thurstone               Thurstone Case V scaling
tr                      Find the trace of a square matrix
vegetables              Paired comparison of preferences for 9
                        vegetables
winsor                  Find the Winsorized scores, means, sds or
                        variances for a vector, matrix, or data.frame
wkappa                  Find Cohen's kappa and weighted kappa
                        coefficients for correlation of two raters
