Learn R Programming
⚠️There's a newer version (2.5.3) of this package.Take me there.

psych (version 1.0-65)

Procedures for Psychological, Psychometric, and Personality Research

Description

A number of routines for personality, psychometrics and experimental psychology. Functions are primarily for scale construction using factor analysis, cluster analysis and reliability analysis, although others provide basic descriptive statistics. Functions for simulating particular item and test structures are included. Several functions serve as a useful front end for structural equation modeling. For more information, see the personality-project.org/r.

Copy Link

Version

Install

install.packages('psych')

Monthly Downloads

240,452

Version

1.0-65

License

GPL version 2 or newer

Maintainer

William Revelle

Last Published

March 21st, 2025

Functions in psych (1.0-65)

ICLUST.cluster

Function to form hierarchical cluster analysis of items
ICC

Intraclass Correlations (ICC1, ICC2, ICC3 from Shrout and Fleiss)
ICLUST

ICLUST: Item Cluster Analysis -- Hierarchical cluster analysis using psychometric principles
count.pairwise

Count number of pairwise cases for a data set with missing (NA) data.
describe.by

Basic summary statistics by group
Promax

Perform promax rotation and return the inter factor angles
heights

A data.frame of the Galton (1888) height and cubit data set.
geometric.mean

Find the geometric mean of a vector or columns of a data.frame.
paired.r

Test the difference between (un)paired correlations
vegetables

Paired comparison of preferences for 9 vegetables
irt.1p

Item Response Theory estimate of theta (ability) using a Rasch (like) model
ellipses

Plot data and 1 and 2 sigma correlation ellipses
VSS

Apply the Very Simple Structure and MAP criteria to determine the appropriate number of factors.
VSS.scree

Plot a scree test
ICLUST.sort

Sort items by absolute size of cluster loadings
cubits

Galton's example of the relationship between height and 'cubit' or forearm length
comorbidity

Convert base rates of two diagnoses and their comorbidity into phi, Yule, and tetrachorics
cluster.loadings

Find item by cluster correlations, corrected for overlap and reliability
bfi

25 Personality items representing 5 factors
cluster.cor

Find correlations of composite variables from a larger matrix
cities

Distances between 11 US cities
headtail

Combine calls to head and tail
alpha

Find two estimates of reliability: Cronbach's alpha and Guttman's Lambda 6.
fa.graph

Graph factor loading matrices
cluster2keys

Convert a cluster vector (from e.g., kmeans) to a keys matrix suitable for scoring item clusters.
mat.regress

Multiple Regression from matrix input
cortest.mat

Chi square tests of whether a single matrix is an identity matrix, or a pair of matrices are equal.
r.test

Tests of significance for correlations
read.clipboard

shortcut for reading from the clipboard
cluster.plot

Plot factor/cluster loadings and assign items to clusters by their highest loading.
sim.structure

Create correlation matrices or data matrices with a particular measurement and structural model
eigen.loadings

Convert eigen vectors and eigen values to the more normal (for psychologists) component loadings
multi.hist

Multiple histograms with density and normal fits on one page
wkappa

Find Cohen's kappa and weighted kappa coefficients for correlation of two raters
winsor

Find the Winsorized scores or means for a vector, matrix, or data.frame
score.multiple.choice

Score multiple choice items and provide basic test statistics
matrix.addition

A function to add two vectors or matrices
factor2cluster

Extract cluster definitions from factor loadings
cosinor

Functions for analysis of circadian or diurnal data
test.psych

Testing of functions in the psych package
bifactor

Three data sets showing a bifactor solution.
cta

Simulate the C(ues) T(endency) A(ction) model of motivation
error.bars

Plot means and confidence intervals
principal

Principal components analysis
psych

A package for personality, psychometric, and psychological research
schmid

Apply the Schmid Leiman transformation to a correlation matrix
ICLUST.graph

create control code for ICLUST graphical output
factor.congruence

Coefficient of factor congruence
print.psych

Print and summary functions for the psych class
error.bars.by

Plot means and confidence intervals for multiple groups
correct.cor

Find dis-attenuated correlations given correlations and reliabilities
VSS.plot

Plot VSS fits
fisherz

Fisher r to z and z to r and confidence intervals
guttman

Alternative estimates of test reliabiity
describe

Basic descriptive statistics useful for psychometrics
galton

Galton's Mid parent child height data
polar

Convert Cartesian factor loadings into polar coordinates
cortest.bartlett

Bartlett's test that a correlation matrix is an identity matrix
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.
scaling.fits

Test the adequacy of simple choice, logistic, or Thurstonian scaling.
error.crosses

Plot x and y error bars
sim.hierarchical

Create a population or sample correlation matrix, perhaps with hierarchical structure.
structure.list

Create factor model matrices from an input list
factor.model

Find R = F F' + U2 is the basic factor model
ICLUST.rgraph

Draw an ICLUST graph using the Rgraphviz package
make.keys

Create a keys matrix for use by score.items or cluster.cor
structure.graph

Draw a structural equation model specified by two measurement models and a structural model
harmonic.mean

Find the harmonic mean of a vector, matrix, or columns of a data.frame
peas

Galton`s Peas
factor.pa

Principal Axis Factor Analysis
omega.graph

Graph hierarchical factor structures
super.matrix

Form a super matrix from two sub matrices.
epi.bfi

13 personality scales from the Eysenck Personality Inventory and Big 5 inventory
circ.tests

Apply four tests of circumplex versus simple structure
iqitems

14 multiple choice IQ items
pairs.panels

SPLOM, histograms and correlations for a data matrix
omega

Calculate the omega estimate of factor saturation
score.alpha

Score scales and find Cronbach's alpha as well as associated statistics
partial.r

Find the partial correlations for a set (x) of variables with set (y) removed.
fa.parallel

Scree plots of data or correlation matrix compared to random ``parallel" matrices
factor.fit

How well does the factor model fit a correlation matrix. Part of the VSS package
interp.median

Find the interpolated sample median, quartiles, or specific quantiles for a vector, matrix, or data frame
p.rep

Find the probability of replication for an F, t, or r and estimate effect size
polychor.matrix

Phi or Yule coefficient matrix to polychoric coefficient matrix
poly.mat

Find polychoric correlations of item data
phi2poly

Convert a phi coefficient to a polychoric correlation
irt.item.diff.rasch

Simple function to estimate item difficulties using IRT concepts
sim.VSS

create VSS like data
simulation.circ

Simulations of circumplex and simple structure
rescale

Function to convert scores to ``conventional " metrics
phi.demo

Create demo data for psychometrics
plot.psych

Plotting functions for the psych package of class ``psych"
smc

Find the Squared Multiple Correlation (SMC) of each variable with the remaining variables in a matrix
VSS.parallel

Compare real and random VSS solutions
score.items

Score item composite scales and find Cronbach's alpha as well as associated statistics
skew

Calculate skew or kurtosis for a vector, matrix, or data.frame
cluster.fit

cluster Fit: fit of the cluster model to a correlation matrix
thurstone

Thurstone Case V scaling
SD

Find the Standard deviation for a vector, matrix, or data.frame - do not return error if there are no cases
factor.rotate

``Hand" rotate a factor loading matrix
table2matrix

Convert a table with counts to a matrix or data.frame representing those counts.
factor.residuals

R* = R- F F'
tr

Find the trace of a square matrix
sat.act

3 Measures of ability: SATV, SATQ, ACT
sim.item

Generate simulated data structures for circumplex or simple structure
sim

Functions to simulate psychological/psychometric data
sim.congeneric

Simulate a congeneric data set
phi

Find the phi coefficient of correlation between two dichotomous variables