constructD: Calculate Somers' d for the constructs.

In OpenRepGrid: Tools to analyse repertory grid data

Description

Calculate Somers' d for the constructs. d is an assymetric association measure as it depends on which variable is set as dependent and independent. The direction of dependency needs to be specified.

Usage

constructD(x, dependent="c", trim=30, index=T, col.index=F, digits=1,
    output=1)

Arguments

x	repgrid object
dependent	A string denoting the direction of dependency in the output table (as d is assymetrical). Possible values are "c" (the default) for setting the columns as dependent, "r" for setting the rows as the dependent variable and "s" for the symmetrical Somers' d measure (the mean of the two directional values for code"c" and "r").
trim	The number of characters a construct is trimmed to (default is 30). If NA no trimming occurs. Trimming simply saves space when displaying correlation of constructs with long names.
index	Whether to print the number of the construct (default is TRUE).
col.index	Logical. Wether to add an extra index column so the column names are indexes instead of construct names. This option renders a neater output as long construct names will stretch the output (default is FALSE).
digits	Numeric. Number of digits to round to (default is 2).
output	The type of output printed to the console. output=0 will supress printing of the output. output=1 (default) will print results to the screen.

Value

matrix of construct correlations.

Note

Thanks to Marc Schwartz for supplying the code to calculate Somers' d.

Author(s)

Mark Heckmann

References

Somers, R. H. (1962). A New Asymmetric Measure of Association for Ordinal Variables. American Sociological Review, 27(6), 799-811.

Examples

## Not run: 

constructD(fbb2003)       # columns as dependent (default)
constructD(fbb2003, "c")  # row as dependent
constructD(fbb2003, "s")  # symmetrical index

# surpress printing
d <- constructD(fbb2003, out=0, trim=5)
d

# more digits
constructD(fbb2003, dig=3)

# add index column, no trimming
constructD(fbb2003, col.index=TRUE, index=F, trim=NA)  


## End(Not run)

OpenRepGrid documentation built on May 2, 2019, 4:54 p.m.