Smooth a non-positive definite correlation matrix to make it positive definite
Distances between 11 US cities
Draw pairs of bargraphs based on two groups
13 personality scales from the Eysenck Personality Inventory and Big 5 inventory
Create dummy coded variables
8 cognitive variables used by Dwyer for an example.
Example data set from Gorsuch (1997) for an example factor extension.
How well does the factor model fit a correlation matrix. Part of the VSS package
Intraclass Correlations (ICC1, ICC2, ICC3 from Shrout and Fleiss)
Apply the Kaiser normalization when rotating factors
Find various goodness of fit statistics for factor analysis and principal components
5 socio-economic variables from Harman (1967)
Compare real and random VSS solutions
Item Response Analysis by Exploratory Factor Analysis of tetrachoric/polychoric correlations
Plot means and confidence intervals
Two way plots of means, error bars, and sample sizes
Convert a phi coefficient to a tetrachoric correlation
Draw an ICLUST graph using the Rgraphviz package
``Hand" rotate a factor loading matrix
Fisher r to z and z to r and confidence intervals
Chi square tests of whether a single matrix is an identity matrix, or a pair of matrices are equal.
Perform bifactor, promax or targeted rotations and return the inter factor angles.
Apply Dwyer's factor extension to find factor loadings for extended variables
Find item by cluster correlations, corrected for overlap and reliability
Logistic transform from x to p and logit transform from p to x
Convert a cluster vector (from e.g., kmeans) to a keys matrix suitable for scoring item clusters.
Find two estimates of reliability: Cronbach's alpha and Guttman's Lambda 6.
Scree plots of data or correlation matrix compared to random ``parallel" matrices
Plot x and y error bars
Seven data sets showing a bifactor solution.
Find miniscales (parcels) of size 2 or 3 from a set of items
Galton's Mid parent child height data
Find the partial correlations for a set (x) of variables with set (y) removed.
Draw an ICLUST hierarchical cluster structure diagram
Plot the successive eigen values for a scree test
Bond's Logical Operations Test -- BLOT
Bootstrapped confidence intervals for raw and composite correlations
Convert correlations to distances (necessary to do multidimensional scaling of correlation data)
Various ways to estimate factor scores for the factor analysis model
Bartlett's test that a correlation matrix is an identity matrix
Apply four tests of circumplex versus simple structure
12 variables created by Schmid and Leiman to show the Schmid-Leiman Transformation
A data set from Cushny and Peebles (1905) on the effect of three drugs on hours of sleep, used by Student (1908)
Sort factor analysis or principal components analysis loadings
Plot means and confidence intervals for multiple groups
Find the Standard deviation for a vector, matrix, or data.frame - do not return error if there are no cases
Combine two square matrices to have a lower off diagonal for one, upper off diagonal for the other
Test the adequacy of simple choice, logistic, or Thurstonian scaling.
Plot data and 1 and 2 sigma correlation ellipses
Draw a correlation ellipse and two normal curves to demonstrate tetrachoric correlation
Bock and Liberman (1970) data set of 1000 observations of the LSAT
iclust: Item Cluster Analysis -- Hierarchical cluster analysis using psychometric principles
9 Cognitive variables discussed by Tucker and Lewis (1973)
Make "radar" or "spider" plots.
The sample size weighted correlation may be used in correlating aggregated data
Convert base rates of two diagnoses and their comorbidity into phi, Yule, and tetrachorics
Galton's example of the relationship between height and 'cubit' or forearm length
Set Correlation and Multiple Regression from matrix or raw input
Score scales and find Cronbach's alpha as well as associated statistics
Apply the Very Simple Structure and MAP criteria to determine the appropriate number of factors.
Create correlation matrices or data matrices with a particular measurement and structural model
Find R = F F' + U2 is the basic factor model
Prediction function for factor analysis or principal components
Eight political variables used by Harman (1967) as example 8.17
Simulate a congeneric data set
A simple demonstration of the Pearson, phi, and polychoric corelation
R* = R- F F'
Draw biplots of factor or component scores by factor or component loadings
Tetrachoric, polychoric, biserial and polyserial correlations from various types of input
Combine calls to head and tail
Create a block randomized structure for n independent variables
Two data sets from Harman (1967). 9 cognitive variables from Holzinger and 8 emotional variables from Burt
Basic summary statistics by group
Plot VSS fits
Find Cohen's kappa and weighted kappa coefficients for correlation of two raters
Convert eigen vectors and eigen values to the more normal (for psychologists) component loadings
3 Measures of ability: SATV, SATQ, ACT
A function to add two vectors or matrices
Find correlations for mixtures of continuous, polytomous, and dichotomous variables
Graph factor loading matrices
Calculate univariate or multivariate (Mardia's test) skew and kurtosis for a vector, matrix, or data.frame
Helper functions for drawing path model diagrams
75 mood items from the Motivational State Questionnaire for 3896 participants
Phi or Yule coefficient matrix to polychoric coefficient matrix
Find the greatest lower bound to reliability.
A utility for basic data cleaning and recoding. Changes values outside of minimum and maximum limits to NA.
A package for personality, psychometric, and psychological research
Graph hierarchical factor structures
Sort the elements of a correlation matrix to reflect factor loadings
16 multiple choice IQ items
Two data sets of affect and arousal scores as a function of personality and movie conditions
Find statistics (including correlations) within and between groups for basic multilevel analyses
A data.frame of the Galton (1888) height and cubit data set.
Thurstone Case V scaling
Count number of pairwise cases for a data set with missing (NA) data.
Find the probability of replication for an F, t, or r and estimate effect size
Find the interpolated sample median, quartiles, or specific quantiles for a vector, matrix, or data frame
NEO correlation matrix from the NEO_PI_R manual
Find the harmonic mean of a vector, matrix, or columns of a data.frame
Find the trace of a square matrix
Simple function to estimate item difficulties using IRT concepts
Testing of functions in the psych package
Find the phi coefficient of correlation between two dichotomous variables
Convert Cartesian factor loadings into polar coordinates
Galton`s Peas
Find the Winsorized scores, means, sds or variances for a vector, matrix, or data.frame
Print and summary functions for the psych class
Score multiple choice items and provide basic test statistics
Correct correlations for restriction of range. (Thorndike Case 2)
25 Personality items representing 5 factors
Simulate a 3 way balanced ANOVA or linear model, with or without repeated measures.
Test the difference between (un)paired correlations
Extract residuals from various psych objects
Plotting functions for the psych package of class ``psych"
Create factor model matrices from an input list
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.
Simulations of circumplex and simple structure
Find von Neuman's Mean Square of Successive Differences
Score item composite scales and find Cronbach's alpha, Guttman lambda 6 and item whole correlations
Extract cluster definitions from factor loadings
Item Response Theory estimate of theta (ability) using a Rasch (like) model
Convert a table with counts to a matrix or data.frame representing those counts.
Find Item Response Theory (IRT) based scores for dichotomous or polytomous items
Correlations of eight physical variables (from Harman, 1966)
shortcut for reading from the clipboard
Simulate multilevel data with specified within group and between group correlations
An example of the distinction between within group and between group correlations
create control code for ICLUST graphical output
Create an image plot for a correlation or factor matrix
Reverse the coding of selected items prior to scale analysis
Find the Kaiser, Meyer, Olkin Measure of Sampling Adequacy
Sort items by absolute size of cluster loadings
Function to form hierarchical cluster analysis of items
Plot factor/cluster loadings and assign items to clusters by their highest loading.
Basic descriptive statistics useful for psychometrics
Functions to simulate psychological/psychometric data.
Paired comparison of preferences for 9 vegetables
US family income from US census 2008
Create a keys matrix for use by score.items or cluster.cor
Convert a data frame, correlation matrix, or factor analysis output to a LaTeX table
Miscellaneous helper functions for the psych package
Function to convert scores to ``conventional
" metrics
11 emotional variables from Burt (1915)
Simulate the C(ues) T(endency) A(ction) model of motivation
Find the geometric mean of a vector or columns of a data.frame.
Draw a scatter plot with associated X and Y histograms, densitie and correlation
Generate simulated data structures for circumplex, spherical, or simple structure
Alternative estimates of test reliabiity
Draw a structural equation model specified by two measurement models and a structural model
Multiple histograms with density and normal fits on one page
Tests of significance for correlations
Find correlations of composite variables from a larger matrix
Create a population or sample correlation matrix, perhaps with hierarchical structure.
cluster Fit: fit of the cluster model to a correlation matrix
Find dis-attenuated correlations given correlations and reliabilities
Exploratory Factor analysis using MinRes (minimum residual) as well as EFA by Principal Axis, Weighted Least Squares or Maximum Likelihood
Coefficient of factor congruence
Find the Squared Multiple Correlation (SMC) of each variable with the remaining variables in a matrix
Form a super matrix from two sub matrices.
Find the correlations, sample sizes, and probability values between elements of a matrix or data.frame.
Functions for analysis of circadian or diurnal data
Plot probability of multiple choice responses as a function of a latent trait
Calculate McDonald's omega estimates of general and total factor saturation
SPLOM, histograms and correlations for a data matrix
Principal components analysis (PCA)
create VSS like data