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