summary.formula: method reverse does not use fun argument
Thanks also to Thomas Lumley for his reply concerning summary.formula in the Hmisc package. See below for some more notes. -FH On Fri, 11 Apr 2003 10:25:41 +0200
Thomas Gerds <gerds at fdm.uni-freiburg.de> wrote:
hi, recently i discovered the functionability summary.formula, awesome! from the help page i understand that method=reverse allows to summarize all variables on the right hand side of formula (the help page on line 229 wrongly refers to the left? hand side variables) in categories which are determined by a single left hand side variable.
Sorry about the typo. You are correct, that should have been "right hand side variables".
my problem is that the argument fun seems not to be compatible with method=reverse!? every continuous variable is summarized in three quantiles.
As stated in the documentation, fun applies only to method='response' and method='cross'.
here is an example: hist is a factor, PET and CT are "numeric" summary(PET~hist,data=her,fun=sum) PET N=47 +-------+------------------+--+---+ | | |N |PET| +-------+------------------+--+---+ |hist |Morbus Hodgkin |18| 81| | |Niedrigmaligne NHL|11| 39| | |Hochmaligne NHL |18| 49| +-------+------------------+--+---+ |Overall| |47|169| +-------+------------------+--+---+
summary(CT~hist,data=her,fun=sum)
CT N=47 +-------+------------------+--+---+ | | |N |CT | +-------+------------------+--+---+ |hist |Morbus Hodgkin |18| 70| | |Niedrigmaligne NHL|11| 16| | |Hochmaligne NHL |18| 32| +-------+------------------+--+---+ |Overall| |47|118| +-------+------------------+--+---+ it would be desirable to combine both tables such that there is one column for PET and one for CT ... is this possible?
Yes, see the documentation. Create a bivariate response variable with cbind and use a bivariate summarization function as 'fun'. And note that using 'stratify(someothervariable)' you can create multiple groups across columns as with method='reverse'; you just can't get statistical tests for them with method='response'. Frank Harrell
trying method=reverse gives: summary(hist~PET+CT,data=her,fun=sum,method="reverse") Descriptive Statistics by hist +------+---------------+-------------------+----------------+ | |Morbus Hodgkin |Niedrigmaligne NHL |Hochmaligne NHL | | |(N=18) |(N=11) |(N=18) | +------+---------------+-------------------+----------------+ |PET |3.00/3.50/6.75 |1.50/3.00/6.00 |1.00/2.00/3.75 | +------+---------------+-------------------+----------------+ |CT : 0| 0% (0) | 36% (4) | 28% (5) | +------+---------------+-------------------+----------------+ | 1 | 11% (2) | 9% (1) | 28% (5) | +------+---------------+-------------------+----------------+ | 2 | 28% (5) | 36% (4) | 11% (2) | +------+---------------+-------------------+----------------+ | 3 | 17% (3) | 9% (1) | 11% (2) | +------+---------------+-------------------+----------------+ | 4 | 11% (2) | 9% (1) | 17% (3) | +------+---------------+-------------------+----------------+ | 5 | 6% (1) | 0% (0) | 6% (1) | +------+---------------+-------------------+----------------+ | 6 | 6% (1) | 0% (0) | 0% (0) | +------+---------------+-------------------+----------------+ | 7 | 11% (2) | 0% (0) | 0% (0) | +------+---------------+-------------------+----------------+ | 8 | 11% (2) | 0% (0) | 0% (0) | +------+---------------+-------------------+----------------+ thanks a lot in advance, tomy
--- Frank E Harrell Jr Prof. of Biostatistics & Statistics Div. of Biostatistics & Epidem. Dept. of Health Evaluation Sciences U. Virginia School of Medicine http://hesweb1.med.virginia.edu/biostat