Find the Kaiser, Meyer, Olkin Measure of Sampling Adequacy
Find the Standard deviation for a vector, matrix, or data.frame - do not return error if there are no cases
Perform bifactor, promax or targeted rotations and return the inter factor angles.
Two data sets of affect and arousal scores as a function of personality and movie conditions
Draw biplots of factor or component scores by factor or component loadings
Distances between 11 US cities
Plot VSS fits
Find item by cluster correlations, corrected for overlap and reliability
12 cognitive variables from Cattell (1963)
25 Personality items representing 5 factors
cluster Fit: fit of the cluster model to a correlation matrix
Find a Full Information Maximum Likelihood (FIML) correlation or covariance matrix from a data matrix with missing data
Plot the successive eigen values for a scree test
Find correlations of composite variables (corrected for overlap) from a larger matrix.
A set of functions for factorial and empirical scale construction
Find two estimates of reliability: Cronbach's alpha and Guttman's Lambda 6.
Convert correlations to distances (necessary to do multidimensional scaling of correlation data)
Apply four tests of circumplex versus simple structure
Sort (order) a dataframe or matrix by multiple columns
A 29 x 29 matrix that produces weird factor analytic results
Smooth a non-positive definite correlation matrix to make it positive definite
Draw pairs of bargraphs based on two groups
Plot factor/cluster loadings and assign items to clusters by their highest loading.
Convert a cluster vector (from e.g., kmeans) to a keys matrix suitable for scoring item clusters.
Simulate the C(ues) T(endency) A(ction) model of motivation
Bartlett's test that a correlation matrix is an identity matrix
Chi square tests of whether a single matrix is an identity matrix, or a pair of matrices are equal.
The sample size weighted correlation may be used in correlating aggregated data
12 variables created by Schmid and Leiman to show the Schmid-Leiman Transformation
Galton's example of the relationship between height and 'cubit' or forearm length
A data set from Cushny and Peebles (1905) on the effect of three drugs on hours of sleep, used by Student (1908)
16 ability items scored as correct or incorrect.
Seven data sets showing a bifactor solution.
Helper functions for drawing path model diagrams
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.
Create a block randomized structure for n independent variables
Bock and Liberman (1970) data set of 1000 observations of the LSAT
Deprecated Exploratory Factor analysis functions. Please use fa
Bond's Logical Operations Test -- BLOT
11 emotional variables from Burt (1915)
Basic descriptive statistics useful for psychometrics
Plot data and 1 and 2 sigma correlation ellipses
Bootstrapped confidence intervals for raw and composite correlations
Create an image plot for a correlation or factor matrix
Create a 'violin plot' or density plot of the distribution of a set of variables
Eysenck Personality Inventory (EPI) data for 3570 participants
Functions for analysis of circadian or diurnal data
Convert eigen vectors and eigen values to the more normal (for psychologists) component loadings
Count number of pairwise cases for a data set with missing (NA) data.
Scree plots of data or correlation matrix compared to random ``parallel" matrices
8 cognitive variables used by Dwyer for an example.
Graph factor loading matrices
Find Cohen d and confidence intervals
Plot means and confidence intervals for multiple groups
Create dummy coded variables
Two way plots of means, error bars, and sample sizes
Draw a correlation ellipse and two normal curves to demonstrate tetrachoric correlation
Perform and Exploratory Structural Equation Model (ESEM) by using factor extension techniques
13 personality scales from the Eysenck Personality Inventory and Big 5 inventory
Galton's Mid parent child height data
Exploratory Factor analysis using MinRes (minimum residual) as well as EFA by Principal Axis, Weighted Least Squares or Maximum Likelihood
Apply Dwyer's factor extension to find factor loadings for extended variables
Sort factor analysis or principal components analysis loadings
Plot means and confidence intervals
Convert base rates of two diagnoses and their comorbidity into phi, Yule, and tetrachorics
Find the correlations, sample sizes, and probability values between elements of a matrix or data.frame.
Multi level (hierarchical) factor analysis
A first approximation to Random Effects Exploratory Factor Analysis
Find R = F F' + U2 is the basic factor model
R* = R- F F'
US family income from US census 2008
Find dis-attenuated correlations given correlations and reliabilities
Find the greatest lower bound to reliability.
Find the geometric mean of a vector or columns of a data.frame.
Find the interpolated sample median, quartiles, or specific quantiles for a vector, matrix, or data frame
``Hand" rotate a factor loading matrix
Alternative estimates of test reliabiity
Plot probability of multiple choice responses as a function of a latent trait
Various ways to estimate factor scores for the factor analysis model
Find Cohen's kappa and weighted kappa coefficients for correlation of two raters
16 multiple choice IQ items
Basic summary statistics by group
Logistic transform from x to p and logit transform from p to x
Apply the Kaiser normalization when rotating factors
Convert a data frame, correlation matrix, or factor analysis output to a LaTeX table
Find correlations for mixtures of continuous, polytomous, and dichotomous variables
Item Response Analysis by Exploratory Factor Analysis of tetrachoric/polychoric correlations
Sort the elements of a correlation matrix to reflect factor loadings
Useful utility functions for file/directory exploration and manipulation.
Transformations of r, d, and t including Fisher r to z and z to r and confidence intervals
A data.frame of the Galton (1888) height and cubit data set.
Draw an ICLUST hierarchical cluster structure diagram
75 mood items from the Motivational State Questionnaire for 3032 unique participants
Find von Neuman's Mean Square of Successive Differences
Plot x and y error bars
Find the probability of replication for an F, t, or r and estimate effect size
75 mood items from the Motivational State Questionnaire for 3896 participants
Show a dot.chart with error bars for different groups or variables
Coefficient of factor congruence
Test the difference between (un)paired correlations
Graph hierarchical factor structures
A function to add two vectors or matrices
NEO correlation matrix from the NEO_PI_R manual
Find and graph Mahalanobis squared distances to detect outliers
Print and summary functions for the psych class
Tests of significance for correlations
Prediction function for factor analysis or principal components
Draw a scatter plot with associated X and Y histograms, densities and correlation
Apply the Schmid Leiman transformation to a correlation matrix
Reverse the coding of selected items prior to scale analysis
Principal components analysis (PCA)
Create a population or sample correlation matrix, perhaps with hierarchical structure.
State Anxiety data from the PMC lab over multiple occasions.
Combine two square matrices to have a lower off diagonal for one, upper off diagonal for the other
Generate simulated data structures for circumplex, spherical, or simple structure
Find the Squared Multiple Correlation (SMC) of each variable with the remaining variables in a matrix
Calculate McDonald's omega estimates of general and total factor saturation
How well does the factor model fit a correlation matrix. Part of the VSS package
A sample from the SAPA Personality Inventory including an item dictionary and scoring keys.
Find the phi coefficient of correlation between two dichotomous variables
Data set testing causal direction in presumed media influence
A simple demonstration (and test) of various IRT scoring algorthims.
Score item composite scales and find Cronbach's alpha, Guttman lambda 6 and item whole correlations
A simple demonstration of the Pearson, phi, and polychoric corelation
Score multiple choice items and provide basic test statistics
Find various goodness of fit statistics for factor analysis and principal components
Simulations of circumplex and simple structure
Extract cluster definitions from factor loadings
Create a keys matrix for use by score.items or cluster.cor
Find the harmonic mean of a vector, matrix, or columns of a data.frame
Correct correlations for restriction of range. (Thorndike Case 2)
Combine calls to head and tail
Function to convert scores to ``conventional
" metrics
Shortcuts for reading from the clipboard or a file
Extract residuals from various psych objects
Miscellaneous helper functions for the psych package
Estimate and display direct and indirect effects of mediators and moderator in path models
Find the partial correlations for a set (x) of variables with set (y) removed.
Calculate univariate or multivariate (Mardia's test) skew and kurtosis for a vector, matrix, or data.frame
Simple function to estimate item difficulties using IRT concepts
Form a super matrix from two sub matrices.
Paired comparison of preferences for 9 vegetables
Functions to simulate psychological/psychometric data.
Find the Winsorized scores, means, sds or variances for a vector, matrix, or data.frame
Convert a table with counts to a matrix or data.frame representing those counts.
Multiple histograms with density and normal fits on one page
Item Response Theory estimate of theta (ability) using a Rasch (like) model
create VSS like data
Find and plot various reliability/gneralizability coefficients for multilevel data
Make "radar" or "spider" plots.
Convert Cartesian factor loadings into polar coordinates
Galton`s Peas
Find statistics (including correlations) within and between groups for basic multilevel analyses
Phi or Yule coefficient matrix to polychoric coefficient matrix
Score scales and find Cronbach's alpha as well as associated statistics
Tetrachoric, polychoric, biserial and polyserial correlations from various types of input
Thurstone Case V scaling
SPLOM, histograms and correlations for a data matrix
Find Item Response Theory (IRT) based scores for dichotomous or polytomous items
A utility for basic data cleaning and recoding. Changes values outside of minimum and maximum limits to NA.
Find miniscales (parcels) of size 2 or 3 from a set of items
Convert a phi coefficient to a tetrachoric correlation
Set Correlation and Multiple Regression from matrix or raw input
Simulate multilevel data with specified within group and between group correlations
3 Measures of ability: SATV, SATQ, ACT
Plotting functions for the psych package of class ``psych"
Test the adequacy of simple choice, logistic, or Thurstonian scaling.
Create correlation matrices or data matrices with a particular measurement and structural model
Simulate a 3 way balanced ANOVA or linear model, with or without repeated measures.
Find the trace of a square matrix
Simulate a congeneric data set
Several indices of the unidimensionality of a set of variables.
Create factor model matrices from an input list
Draw a structural equation model specified by two measurement models and a structural model
Testing of functions in the psych package
Find various test-retest statistics, including test, person and item reliability
An example of the distinction between within group and between group correlations
Intraclass Correlations (ICC1, ICC2, ICC3 from Shrout and Fleiss)
Example data set from Gorsuch (1997) for an example factor extension.
Function to form hierarchical cluster analysis of items
Data from the sexism (protest) study of Garcia, Schmitt, Branscome, and Ellemers (2010)
Example data from Gleser, Cronbach and Rajaratnam (1965) to show basic principles of generalizability theory.
Five data sets from Harman (1967). 9 cognitive variables from Holzinger and 8 emotional variables from Burt
create control code for ICLUST graphical output
Decision Theory measures of specificity, sensitivity, and d prime
iclust: Item Cluster Analysis -- Hierarchical cluster analysis using psychometric principles
The Schutz correlation matrix example from Shapiro and ten Berge
Draw an ICLUST graph using the Rgraphviz package
Apply the Very Simple Structure, MAP, and other criteria to determine the appropriate number of factors.
Sort items by absolute size of cluster loadings
A package for personality, psychometric, and psychological research
Compare real and random VSS solutions
9 Cognitive variables discussed by Tucker and Lewis (1973)