In article <[EMAIL PROTECTED]>,
Dennis Roberts <[EMAIL PROTECTED]> wrote:
>At 09:09 AM 6/7/03 -0500, Herman Rubin wrote:
>>While it is very often done, it is improper for the
>>statistician to construct the model; if the user
>>cannot make the assumptions, the statistician is no
>>longer a consultant, but a coauthor.
>C'mon Herman ... what IS the role then of the statistician ... just to run
>data? ...
The role of the statistician is to advise the person with
the statistical problem on how to treat it, often devising
new algorithms in the process. It is also to question the
investigator about the assumptions, and to point out what
assumptions make little difference.
>You can't expect every person who has a legitimate interest in "data" to be
>a "true" statistician ... just like we can't expect every person who has a
>valid interest in weather phenomena ... to know all the intricate facts and
>"history" about weather ...
I never claimed this. The investigator, however, is the one
who must make the probability assumptions about the data.
>I would argue that a major role of a professional statistician is to HELP
>others ... and assist them to see what are valid approaches to doing things
>with data and help them understand the underlying assumptions that are and
>have to be made
It is often the case that the assumptions are even more
important than the data. It can even be the case that for
some aspects the data is more important, for others the
assumptions.
>And, as far as being a coauthor ... what's wrong with that? In fact, the
>coauthor model is an excellent one ... as long as both have made important
>contributions to the paper ...
As a coauthor, it is still important not to use statistical
convenience for making assumptions which affect the results,
rather than going back to the subject matter field.
My "commandments" bear repeating.
I am often requested to repost my five commandments. These are
posted here without exegesis.
For the client:
1. Thou shalt know that thou must make assumptions.
2. Thou shalt not believe thy assumptions.
For the consultant:
3. Thou shalt not make thy client's assumptions for him.
4. Thou shalt inform thy client of the consequences
of his assumptions.
For the person who is both (e. g., a biostatistician or psychometrician):
5. Thou shalt keep thy roles distinct, lest thou violate
some of the other commandments.
The consultant is obligated to point out how their assumptions affect
their views of their domain; this is in the 4-th commandment. But the
consultant should be very careful in the assumption-making process not
to intrude beyond possibly pointing out that certain assumptions make
large differences, while others do not. A good example here is regression
analysis, where often normality has little effect, but the linearity of
the model is of great importance. Thus, it is very important for the
client to have to justify transformations.
There are, unfortunately, many fields in which much of the activity
consists of using statistical procedures without regard for any assumptions.
>I do agree that software makes "output" easy to come by but, that is a
>totally different matter ...
Not really. The oracle only answers the questions asked,
not the real questions. One does not just approach the
altar, pay the priest his fee, present the sacrifice, and
expect a miracle to provide the state of the universe.
--
This address is for information only. I do not claim that these views
are those of the Statistics Department or of Purdue University.
Herman Rubin, Deptartment of Statistics, Purdue University
[EMAIL PROTECTED] Phone: (765)494-6054 FAX: (765)494-0558
.
.
=================================================================
Instructions for joining and leaving this list, remarks about the
problem of INAPPROPRIATE MESSAGES, and archives are available at:
. http://jse.stat.ncsu.edu/ .
=================================================================
