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