IntervalData            Create an 'IntervalData' object
IntervalData-class      S4 class representing a single interval
IntervalDataOrIntervalList-class
                        Virtual union of 'IntervalData' and
                        'IntervalList' classes
IntervalList            Create an 'IntervalList' object
IntervalList-class      S4 class representing a list of intervals
IntervalListOrIntervalMatrix-class
                        Virtual union of 'IntervalList' and
                        'IntervalMatrix' classes
IntervalMatrix          Create an 'IntervalMatrix' object
IntervalMatrix-class    S4 class representing a matrix of intervals
IntervalQuestionStat-package
                        Tools to Deal with Interval-Valued Responses in
                        Questionnaires
apply                   Apply functions over 'IntervalMatrix' margins
arithmetic              Interval arithmetic operations
as.IntervalData         Convert a real number into a degenerate
                        interval
as.IntervalList         Convert a single interval to a list of
                        intervals
c                       Combine 'IntervalData' and 'IntervalList'
                        objects
cbind                   Combine 'IntervalList' and 'IntervalMatrix'
                        objects by columns
cov                     Calculate the sample covariance between two
                        random intervals
cronbach                Estimate sample Cronbach's alpha coefficient
dim                     Get the number of rows and columns of an
                        'IntervalMatrix' object
distance                Calculate the theta-distance between two
                        intervals
extract                 Extract and replace parts of an interval-valued
                        object
ivs2likert              Convert interval-valued responses into their
                        equivalent numerically encoded Likert-type
                        scale answers with minimum theta-distance
                        criterion
ivs2vas                 Convert interval-valued responses into
                        equivalent visual analogue scale answers
                        through mid-point criterion
lackinfo                Lack of information in expository face-to-face
                        lessons data set
length                  Get the length of an 'IntervalList' object
mean                    Calculate the sample Aumann mean of a random
                        interval
mid                     Extract and replace the mid-points of
                        interval-valued objects
ncol                    Get the number of columns of an
                        'IntervalMatrix' object
nrow                    Get the number of rows of an 'IntervalMatrix'
                        object
plot                    Plot a single interval or a list of intervals
rbind                   Combine 'IntervalList' and 'IntervalMatrix'
                        objects by rows
show                    Print basic information of interval-valued data
simulIVS                Simulation of interval-valued responses to a
                        questionnaire
spr                     Extract and replace the spreads of
                        interval-valued objects
sum                     Calculate the sum of n intervals
var                     Calculate the sample Fréchet variance of a
                        random interval
