Learn R Programming

⚠️There's a newer version (2.5.6) of this package.Take me there.

psych (version 1.0-42)

Procedures for Personality and Psychological Research

Description

A number of routines for personality, psychometrics and experimental psychology. Functions are primarily for scale construction, cluster analysis and reliability analysis, although others provide basic descriptive statistics. For more information, see the personality-project.org/r.

Copy Link

Version

Install

install.packages('psych')

Monthly Downloads

186,036

Version

1.0-42

License

GPL version 2 or newer

Maintainer

William Revelle

Last Published

June 23rd, 2025

Functions in psych (1.0-42)

headtail

Combine calls to head and tail
Yule

From a two by two table, find the Yule coefficient, convert to phi, or polychoric, recreate table the table to create the Yule coefficient.
omega.graph

Graph hierarchical factor structures
phi.demo

Create demo data for psychometrics
psych

A package for personality, psychometric, and psychological research
ICLUST.sort

Sort items by absolute size of cluster loadings
ICLUST.cluster

Function to form hierarchical cluster analysis of items
score.items

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

Galton's Mid parent child height data
VSS.scree

Plot a scree test
VSS

Apply the Very Simple Structure criterion to determine the appropriate number of factors.
ellipses

Plot data and 1 and 2 sigma correlation ellipses
circ.simulation

Simulations of circumplex and simple structure
error.bars.by

Plot means and confidence intervals for multiple groups
circ.tests

Apply four tests of circumplex versus simple structure
paired.r

Test the difference between (un)paired correlations
mat.regress

Multiple Regression from matrix input
ICLUST.graph

create control code for ICLUST graphical output
bfi

25 Personality items representing 5 factors
eigen.loadings

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

How well does the factor model fit a correlation matrix. Part of the VSS package
correct.cor

Find dis-attenuated correlations and give alpha reliabilities
ICLUST.rgraph

Draw an ICLUST graph using the Rgraphviz package
cluster.plot

Plot factor/cluster loadings and assign items to clusters by their highest loading
error.crosses

Plot x and y error bars
omega

Calculate the omega estimate of factor saturation
VSS.plot

Plot VSS fits
VSS.simulate

create VSS like data
ICLUST

ICLUST: Item Cluster Analysis -- Hierarchical cluster analysis using psychometric principles
skew

Calculate skew for a vector, matrix, or data.frame
read.clipboard

shortcut for reading from the clipboard
VSS.parallel

Compare real and random VSS solutions
fa.graph

Graph factor loading matrices
fa.parallel

Scree plots of data or correlation matrix compared to random ``parallel" matrices
irt.1p

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

Find the phi coefficient of correlation between two dichotomous variables
factor.congruence

Coefficient of factor congruence
score.alpha

Score scales and find Cronbach's alpha as well as associated statistics
schmid

Apply the Schmid Leiman transformation to a correlation matrix
cubits

Galton's example of the relationship between height and 'cubit' or forearm length
harmonic.mean

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

Find item by cluster correlations, corrected for overlap and reliability
alpha.scale

Cronbach alpha for a scale
count.pairwise

Count number of pairwise cases for a data set with missing (NA) data.
item.sim

Generate simulated data structures for circumplex or simple structure
heights

A data.frame of the Galton (1888) height and cubit data set.
error.bars

Plot means and confidence intervals
factor.rotate

``Hand" rotate a factor loading matrix
fisherz

Fisher r to z and z to r and confidence intervals
interp.median

Find the interpolated sample median, quartiles, or specific quantiles for a vector, matrix, or data frame
factor2cluster

Extract cluster definitions from factor loadings
factor.model

Find R = F F' + U2 is the basic factor model
describe

Basic descriptive statistics useful for psychometrics
factor.pa

Principal Axis Factor Analysis
geometric.mean

Find the geometric mean of a vector or columns of a data.frame.
cluster.cor

Find correlations of composite variables from a larger matrix
polar

Convert Cartesian factor loadings into polar coordinates
factor.residuals

R* = R- F F'
polychor.matrix

Phi or Yule coefficient matrix to polychoric coefficient matrix
sat.act

3 Measures of ability: SATV, SATQ, ACT
peas

Galton`s Peas
phi2poly

Convert a phi coefficient to a polychoric correlation
multi.hist

Multiple histograms with density and normal fits on one page
irt.item.diff.rasch

Simple function to estimate item difficulties using IRT concepts
p.rep

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

Create a population or sample correlation matrix with hierachical structure.
r.test

Tests of significance for correlations
poly.mat

Find polychoric correlations of item data
matrix.addition

A function to add two vectors or matrices
score.multiple.choice

Score multiple choice items and provide basic test statistics
winsor

Find the Winsorized mean for a vector, matrix, or data.frame
table2matrix

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

14 multiple choice IQ items
principal

Principal components analysis
test.psych

Testing of functions in the psych package
kurtosi

Kurtosis of a vector, matrix, or data frame
cluster.fit

cluster Fit: fit of the cluster model to a correlation matrix
congeneric.sim

Simulate a congeneric data set
describe.by

Basic summary statistics by group
pairs.panels

SPLOM, histograms and correlations for a data matrix
rescale

Function to convert scores to ``conventional " metrics