Compute Descriptive Summary Statistics of Groups in a cgPairedDifferenceData object
Description
Create a table of quantiles and other summary statistics of the data in a
cgPairedDifferenceData
object.
Usage
1 2  ## S4 method for signature 'cgPairedDifferenceData'
descriptiveTable(data, display = "print", ...)

Arguments
data 
A 
display 
One of three valid values:

... 
Additional arguments. Currently only one is valid:

Details
The returned table contains quantiles, means, sample sizes, and
estimates of variability for each group, and also for the paired
differences.
It also presents the same
summary measures for the paired differences from the groups.
If the logscale
option is specified (either explicitly, or implicitly
from the cgPairedDifferenceData
object), then the geometric mean and
geometric standard error for each of the two groups are included. Also
included are summary measures of the ratio and percent forms of the paired
differences. See the Value section below for details.
Value
Creates an object of class cgPairedDifferenceDescriptiveTable
, with the
following slots:
contents
The table of descriptive summary statistics for each group, and also for paired differences. See below for the data frame structure of the table.
settings
A list of settings carried from the
cgPairedDifferenceData
data
object. These are used for theprint.cgPairedDifferenceDescriptiveTable
method, invoked for example whendisplay="print"
.
The data frame structure of the descriptive table in a contents
slot consists of row.names
that specify the group or paired
difference, and these columns:
n
The sample size.
Min
The minimum value.
25%ile
The 25th percentile, estimated with the
quantile
function.Median
The median value.
75%ile
The 75th percentile, estimated with the
quantile
function.Max
The maximum value.
Mean
The arithmetic mean value.
StdDev
The standard deviation value.
StdErr
The standard error value.
If logscale=TRUE
, then two additional columns are added:
GeoMean
The geometric mean value of the group.
SEGeoMean
The estimated standard error associated with the geometric mean. This is calculated with the Delta Method, and will particularly lose accuracy in its useful approximation once the standard error in the log scale exceeds 0.50. A warning message is issued when this occurs.
The third row of simple difference summaries
has GeoMean
and SEGeoMean
are set to <NA>.
Fourth and fifth rows are also added with summaries of the paired
ratio differences and percent differences. The StdDev
and
StdErr
values are set to <NA> in these two rows.
The GeoMean
and SEGeoMean
values are calculated via the
the Delta Method, with the same caveats described above.
Note
Contact cg@billpikounis.net for bug reports, questions, concerns, and comments.
Author(s)
Bill Pikounis [aut, cre, cph], John Oleynick [aut], Eva Ye [ctb]
Examples
1 2 3 4 5 6 7 8 9 10 11 12 13 14  data(anorexiaFT)
anorexiaFT.data < prepareCGPairedDifferenceData(anorexiaFT, format="groupcolumns",
analysisname="Anorexia FT",
endptname="Weight",
endptunits="lbs",
expunitname="Patient",
digits=1, logscale=TRUE)
descriptiveTable(anorexiaFT.data)
## Remove the geometric mean and standard error columns,
## and the Ratio / Percent Rows, since they are no longer applicable.
descriptiveTable(anorexiaFT.data, logscale=FALSE)
