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