[R] Decision Trees /Decision Analysis with R?

[Jonathan Daily]

So TreeAge fits models but won't predict from them? That seems like
bizarre behavior. I suppose I would recommend, then, looking at the
source code from the aforementioned packages for how they store their
split data. It sounds like you would have to write code to hack
TreeAge outputs into another packages' format (e.g. look at
?rpart.object).

Sorry I couldn't help more,
Jon

On Wed, Jun 8, 2011 at 9:47 AM, stefan.duke at gmail.com
<stefan.duke at gmail.com> wrote:
> Thank you so much for reply. But I am looking for the exact opposite.
>
> I do not have a data set which I want to partition. But already a
> sequence/tree-like set of decision rules and with which I want to
> simulate what is my expected outcome/pay-off given a particular
> scenario.
> As far as I understand it, those packages could calculate the expected
> outcome AFTER having fit them to a particular data set and not
> construct a "synthetic" tree with exogenously defined decision
> nods/rules. Or am I wrong?
>
>
> Thanks and best,
> Stefan
>
>
>
> On Wed, Jun 8, 2011 at 2:03 PM, Jonathan Daily <biomathjdaily at gmail.com> wrote:
>> See packages rpart, randomForest, party.
>>
>> Also, typing "R Decision Trees" produced good google results.
>>
>> http://www.google.com/search?aq=f&sourceid=chrome&ie=UTF-8&q=R+Decision+Trees
>>
>> On Wed, Jun 8, 2011 at 7:02 AM, stefan.duke at gmail.com
>> <stefan.duke at gmail.com> wrote:
>>> Hello,
>>>
>>> this question is a bit out of the blue.
>>>
>>> I am a big R fan and user and in my new job I do some decision
>>> modeling (mostly health economics). For that decision trees are often
>>> used (I guess the most classic example is the investment decision A,
>>> B, and C with different probabilities, what is the expected payoff).
>>> We use a specialized software called TreeAge that some might know.
>>> The basic setup of such simulations is actually very simple and I
>>> guess useful in many fields. So I was wondering whether there is
>>> already a package out there in R that is doing such a thing?
>>>
>>> Thanks for any hints!
>>> Best,
>>> Stefan
>>>
>>> PS
>>> (By decision tree I don't mean cluster-like analysis of a data set
>>> splitting by identifying decision nods, but the other way around: I
>>> have decision nodes, what is my expected outcome.)
>>>
>>> ______________________________________________
>>> R-help at r-project.org mailing list
>>> https://stat.ethz.ch/mailman/listinfo/r-help
>>> PLEASE do read the posting guide http://www.R-project.org/posting-guide.html
>>> and provide commented, minimal, self-contained, reproducible code.
>>>
>>
>>
>>
>> --
>> ===============================================
>> Jon Daily
>> Technician
>> ===============================================
>> #!/usr/bin/env outside
>> # It's great, trust me.
>>
>



-- 
===============================================
Jon Daily
Technician
===============================================
#!/usr/bin/env outside
# It's great, trust me.