Entire Organization Switching from SAS to R - Any experience?

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Entire Organization Switching from SAS to R - Any experience?

Lamke
My institute has been heavily dependent on SAS for the past while, and
SAS is starting to charge us a very deep amount for license renewal.
Since we are a non-profit organization that is definitely not
sustainable.  The team is brainstorming possibility of switching to R,
at least gradually.  I am talking about the entire institute with
considerable number of analysts using SAS their entire career.
There’s a handful of us using R regularly.  What kind of problems and
challenges have you faced?  Any insight is much appreciated.  Thank
you very much!

Kelvin

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Re: Entire Organization Switching from SAS to R - Any experience?

milton ruser
*hum*

How much of the "employes" of your institute use statistical softwares? 1-5?
5-20? 20-50?
I think a brief description could help on the discussion.

cheers

milton


On Thu, Jul 16, 2009 at 5:40 PM, Kel Lam <[hidden email]> wrote:

> My institute has been heavily dependent on SAS for the past while, and
> SAS is starting to charge us a very deep amount for license renewal.
> Since we are a non-profit organization that is definitely not
> sustainable.  The team is brainstorming possibility of switching to R,
> at least gradually.  I am talking about the entire institute with
> considerable number of analysts using SAS their entire career.
> There’s a handful of us using R regularly.  What kind of problems and
> challenges have you faced?  Any insight is much appreciated.  Thank
> you very much!
>
> Kelvin
>
> ______________________________________________
> [hidden email] mailing list
> https://stat.ethz.ch/mailman/listinfo/r-help
> PLEASE do read the posting guide
> http://www.R-project.org/posting-guide.html<http://www.r-project.org/posting-guide.html>
> and provide commented, minimal, self-contained, reproducible code.
>
        [[alternative HTML version deleted]]


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Re: Entire Organization Switching from SAS to R - Any experience?

Frank Harrell
In reply to this post by Lamke
Kel Lam wrote:

> My institute has been heavily dependent on SAS for the past while, and
> SAS is starting to charge us a very deep amount for license renewal.
> Since we are a non-profit organization that is definitely not
> sustainable.  The team is brainstorming possibility of switching to R,
> at least gradually.  I am talking about the entire institute with
> considerable number of analysts using SAS their entire career.
> There’s a handful of us using R regularly.  What kind of problems and
> challenges have you faced?  Any insight is much appreciated.  Thank
> you very much!
>
> Kelvin

One of your challenges will be that with the increased productivity of
the team you will have time for more intellectually challenging
problems.  That frustrates some people.

Frank

--
Frank E Harrell Jr   Professor and Chair           School of Medicine
                      Department of Biostatistics   Vanderbilt University

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Frank Harrell
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Re: Entire Organization Switching from SAS to R - Any experience?

Kum-Hoe Hwang
I work for a research institute. I have used R for several years.
I think there are some good and bad sides followings:

Good sides are: I can use new statistical methods from R. no license fee..

Bad sides are : physical memory in PC is an obstacle (max. 3GB), some
package of R is still being developed(unstable-not really a problem), kind
manual( this will be OK if you have training from some R company)

k Hwang
On Fri, Jul 17, 2009 at 10:51 AM, Frank E Harrell Jr <
[hidden email]> wrote:

> Kel Lam wrote:
>
>> My institute has been heavily dependent on SAS for the past while, and
>> SAS is starting to charge us a very deep amount for license renewal.
>> Since we are a non-profit organization that is definitely not
>> sustainable.  The team is brainstorming possibility of switching to R,
>> at least gradually.  I am talking about the entire institute with
>> considerable number of analysts using SAS their entire career.
>> There’s a handful of us using R regularly.  What kind of problems and
>> challenges have you faced?  Any insight is much appreciated.  Thank
>> you very much!
>>
>> Kelvin
>>
>
> One of your challenges will be that with the increased productivity of the
> team you will have time for more intellectually challenging problems.  That
> frustrates some people.
>
> Frank
>
> --
> Frank E Harrell Jr   Professor and Chair           School of Medicine
>                     Department of Biostatistics   Vanderbilt University
>
> ______________________________________________
> [hidden email] 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.
>


--
Kum-Hoe Hwang, Ph.D.

Phone : 82-31-250-3516
Email : [hidden email]

        [[alternative HTML version deleted]]


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Re: Entire Organization Switching from SAS to R - Any experience?

David Winsemius

On Jul 16, 2009, at 10:17 PM, Kum-Hoe Hwang wrote:

> I work for a research institute. I have used R for several years.
> I think there are some good and bad sides followings:
>
> Good sides are: I can use new statistical methods from R. no license  
> fee..
>
> Bad sides are : physical memory in PC is an obstacle (max. 3GB),

The limits are not that small on either Mac OS X or Linux systems.

> some
> package of R is still being developed(unstable-not really a  
> problem), kind
> manual( this will be OK if you have training from some R company)
>
> k Hwang
> On Fri, Jul 17, 2009 at 10:51 AM, Frank E Harrell Jr <
> [hidden email]> wrote:
>
>> Kel Lam wrote:
>>
>>> My institute has been heavily dependent on SAS for the past while,  
>>> and
>>> SAS is starting to charge us a very deep amount for license renewal.
>>> Since we are a non-profit organization that is definitely not
>>> sustainable.  The team is brainstorming possibility of switching  
>>> to R,
>>> at least gradually.  I am talking about the entire institute with
>>> considerable number of analysts using SAS their entire career.
>>> There’s a handful of us using R regularly.  What kind of problems  
>>> and
>>> challenges have you faced?  Any insight is much appreciated.  Thank
>>> you very much!
>>>
>>> Kelvin
>>>
>>
>> One of your challenges will be that with the increased productivity  
>> of the
>> team you will have time for more intellectually challenging  
>> problems.  That
>> frustrates some people.
>>
>> Frank
>>
>> --
>> Frank E Harrell Jr   Professor and Chair           School of Medicine
>>                    Department of Biostatistics   Vanderbilt  
>> University
>>
>> ______________________________________________
> Kum-Hoe Hwang, Ph.D.
>
> Phone : 82-31-250-3516
> Email : [hidden email]
>
> [[alternative HTML version deleted]]


David Winsemius, MD
Heritage Laboratories
West Hartford, CT

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Re: Entire Organization Switching from SAS to R - Any experience?

Mike Prager
In reply to this post by Lamke
Kel Lam <[hidden email]> wrote:

> My institute has been heavily dependent on SAS for the past while, and
> SAS is starting to charge us a very deep amount for license renewal.
> Since we are a non-profit organization that is definitely not
> sustainable.  The team is brainstorming possibility of switching to R,
> at least gradually.  I am talking about the entire institute with
> considerable number of analysts using SAS their entire career.
> There’s a handful of us using R regularly.  What kind of problems and
> challenges have you faced?  Any insight is much appreciated.  Thank
> you very much!
>
> Kelvin

Background: I used SAS intensively for about 15 yr, I used
Systat for about 5 yr, and now I use R almost exclusively. The
group I work with has changed from mostly SAS to mostly R over
the years.

My advice is, think about training. Because SAS and R have such
different models of how statistical programming is structured,
it's not trivial to switch from one to the other.

A lot will depend on what sort of work you are doing. The main
problem we've experienced is that R does not easily handle very
large datasets on standard PC hardware. We still do some
processing with SAS in those cases, though we've been able to
reduce the number of SAS licenses we need.


--
Mike Prager, NOAA, Beaufort, NC
* Opinions expressed are personal and not represented otherwise.
* Any use of tradenames does not constitute a NOAA endorsement.

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Re: Entire Organization Switching from SAS to R - Any experience?

Lamke
I should elaborate the situation a bit more.  We store our data in UNIX and have been using UNIX SAS for our work.  My Biostat dept has 40 SAS users from which at most 10 also use R.  The Epi/Grad Students/Investigators combine for another 30-40 not-so-frequent SAS users let alone R.  So we are talking about 80 folks/workhorses in the entire institute.  

One of my thoughts is to break up the Biostat group into two so that one uses R solely to reduce the number of licences.   IMHO, the pro is to worry a smaller group of users.  However, the cons will be who to be assigned to respective group.  

>A lot will depend on what sort of work you are doing. The main
>problem we've experienced is that R does not easily handle very
>large datasets on standard PC hardware. We still do some
>processing with SAS in those cases, though we've been able to
>reduce the number of SAS licenses we need.


--
Mike Prager, NOAA, Beaufort, NC
* Opinions expressed are personal and not represented otherwise.
* Any use of tradenames does not constitute a NOAA endorsement.

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Re: Entire Organization Switching from SAS to R - Any experience?

Marc Schwartz-3
On Jul 17, 2009, at 9:57 AM, Kelvin Lam wrote:

>
> I should elaborate the situation a bit more.  We store our data in  
> UNIX and
> have been using UNIX SAS for our work.  My Biostat dept has 40 SAS  
> users
> from which at most 10 also use R.  The Epi/Grad Students/Investigators
> combine for another 30-40 not-so-frequent SAS users let alone R.  So  
> we are
> talking about 80 folks/workhorses in the entire institute.
>
> One of my thoughts is to break up the Biostat group into two so that  
> one
> uses R solely to reduce the number of licences.   IMHO, the pro is  
> to worry
> a smaller group of users.  However, the cons will be who to be  
> assigned to
> respective group.

You have several business, human behavior and budgetary issues to  
consider. It is not usually just a matter of making the business case  
that saving annual license costs is the sole factor in making a  
decision to switch to R.

You have to consider the receptivity of the existing base of SAS users  
to changing to R. Are they open to it or are they not motivated to  
change? In the latter case, is the organization in a position of  
forcing change or not? Being a non-profit organization, you can simply  
say, due to funding issues, we are going to have to eliminate some 'x'  
number of SAS licenses to stay within our operating budget. That will  
have an impact on how many users can in fact continue to use SAS.

However, if you compel wholesale change, are you at risk of losing  
people who are resistant and decide to move on? Are they key people  
where their loss would have substantive impact on the organization and  
project commitments, at least in the short term? Yes, on one level, we  
can all be replaced by somebody else, but at what short term cost to  
the organization and it's customers?

If there is resistance amongst some proportion of the staff, an  
incremental approach would be very appropriate. Balance your funding  
issues with the number of staff that would be impacted in the near  
term. Can you eliminate 'x' SAS licenses this year, 'y' more next year  
and so on so that the transition is implemented over a multi year time  
frame while still working within your funding constraints?

Solicit feedback from the staff to see who is open to using R and who  
is not. Let that be a key factor in any decisions to partition the  
staff. Get an idea as to the scale of the battle that you are facing  
with respect to change. Identify the "low hanging fruit" to look for  
incremental and consistent wins that you can build on. Those who are  
resistant to R may simply need time to see that what they have done in  
SAS can indeed be done in R with greater quality, speed, flexibility  
and in time, at a lower cost. Once they get over that hurdle, they may  
come on board with you and make subsequent transitions easier.

With an eye towards the future, be sure that new hires are skilled in  
R, so that as you may need to deal with staff turnover or growth, you  
are enabling the future use of R by a growing number of folks who have  
pre-existing R skills. Set yourself up for future success.

Consider R related training and the costs associated with it. The  
costs are not just what you may have to pay for training, but the  
opportunity costs in the short term of getting people up to speed and  
the loss of productivity short term, even though as Frank noted, you  
will realize notable gains in the long term. Consider how your  
existing project commitments would be impacted and how you may have to  
allocate or re-allocate the workload during the transition.

Consider the costs and timelines associated with converting an  
existing base of SAS code that has perhaps gone through a review and  
validation process. What will it take to replicate that functionality  
in R with the same level of reliability? What methodological issues  
will you face in the transition from SAS to R, given the differing  
philosophies? How long will it take, who will do it and what other  
tasks or projects may be impacted during the transition?

In some environments (eg. Big Pharma), re-training and especially code  
conversion/validation costs alone outweigh the savings of not paying  
for SAS licenses. This is why there is a significant hurdle to using R  
in that environment even though such companies may pay SAS millions of  
dollars per year.

I don't know that there is a one size fits all approach to moving from  
SAS to R. Each operating environment has its own characteristics  
relative to budgets, politics, people and so forth. The points that I  
raise above may be typical but only some may apply to your situation  
and there may be others that I have not raised.

HTH,

Marc Schwartz

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Re: Entire Organization Switching from SAS to R - Any experience?

Ross Boylan
In reply to this post by Lamke
We use SAS and R here (a biostat department and consulting unit), in
part because there are some things SAS does that R doesn't.  In
particular, we use SAS proc nlmixed with custom likelihood functions.  R
has similar capability but does not allow custom likelihood; the authors
say adding it would be non-trivial.

I don't know how common such absolute barriers are, but they would be
one thing to watch for.  As others have noted, datasets too big too fit
in memory are difficult in R (though the 3G barrier only applies to 32
bit hardware).

If you have "customers" who themselves do data analysis, they may also
resist change.

I would think switching from SAS to R is a pretty big deal; it would
probably be easier if you did not need to switch existing projects.  Of
course, that still leaves you paying some license fees.  But the switch
will have substantial short-term costs in time, if not money, even if
users are motivated.

Ross Boylan

On Thu, 2009-07-16 at 17:40 -0400, Kel Lam wrote:

> My institute has been heavily dependent on SAS for the past while, and
> SAS is starting to charge us a very deep amount for license renewal.
> Since we are a non-profit organization that is definitely not
> sustainable.  The team is brainstorming possibility of switching to R,
> at least gradually.  I am talking about the entire institute with
> considerable number of analysts using SAS their entire career.
> There’s a handful of us using R regularly.  What kind of problems and
> challenges have you faced?  Any insight is much appreciated.  Thank
> you very much!
>
> Kelvin
>
> ______________________________________________
> [hidden email] 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.

______________________________________________
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Re: Entire Organization Switching from SAS to R - Any experience?

Frank Harrell
In reply to this post by Marc Schwartz-3
I differ with Marc in one way.  It is amazing what people can learn when
  you create an emergency for them to do so.

Frank


Marc Schwartz wrote:

> On Jul 17, 2009, at 9:57 AM, Kelvin Lam wrote:
>
>>
>> I should elaborate the situation a bit more.  We store our data in
>> UNIX and
>> have been using UNIX SAS for our work.  My Biostat dept has 40 SAS users
>> from which at most 10 also use R.  The Epi/Grad Students/Investigators
>> combine for another 30-40 not-so-frequent SAS users let alone R.  So
>> we are
>> talking about 80 folks/workhorses in the entire institute.
>>
>> One of my thoughts is to break up the Biostat group into two so that one
>> uses R solely to reduce the number of licences.   IMHO, the pro is to
>> worry
>> a smaller group of users.  However, the cons will be who to be
>> assigned to
>> respective group.
>
> You have several business, human behavior and budgetary issues to
> consider. It is not usually just a matter of making the business case
> that saving annual license costs is the sole factor in making a decision
> to switch to R.
>
> You have to consider the receptivity of the existing base of SAS users
> to changing to R. Are they open to it or are they not motivated to
> change? In the latter case, is the organization in a position of forcing
> change or not? Being a non-profit organization, you can simply say, due
> to funding issues, we are going to have to eliminate some 'x' number of
> SAS licenses to stay within our operating budget. That will have an
> impact on how many users can in fact continue to use SAS.
>
> However, if you compel wholesale change, are you at risk of losing
> people who are resistant and decide to move on? Are they key people
> where their loss would have substantive impact on the organization and
> project commitments, at least in the short term? Yes, on one level, we
> can all be replaced by somebody else, but at what short term cost to the
> organization and it's customers?
>
> If there is resistance amongst some proportion of the staff, an
> incremental approach would be very appropriate. Balance your funding
> issues with the number of staff that would be impacted in the near term.
> Can you eliminate 'x' SAS licenses this year, 'y' more next year and so
> on so that the transition is implemented over a multi year time frame
> while still working within your funding constraints?
>
> Solicit feedback from the staff to see who is open to using R and who is
> not. Let that be a key factor in any decisions to partition the staff.
> Get an idea as to the scale of the battle that you are facing with
> respect to change. Identify the "low hanging fruit" to look for
> incremental and consistent wins that you can build on. Those who are
> resistant to R may simply need time to see that what they have done in
> SAS can indeed be done in R with greater quality, speed, flexibility and
> in time, at a lower cost. Once they get over that hurdle, they may come
> on board with you and make subsequent transitions easier.
>
> With an eye towards the future, be sure that new hires are skilled in R,
> so that as you may need to deal with staff turnover or growth, you are
> enabling the future use of R by a growing number of folks who have
> pre-existing R skills. Set yourself up for future success.
>
> Consider R related training and the costs associated with it. The costs
> are not just what you may have to pay for training, but the opportunity
> costs in the short term of getting people up to speed and the loss of
> productivity short term, even though as Frank noted, you will realize
> notable gains in the long term. Consider how your existing project
> commitments would be impacted and how you may have to allocate or
> re-allocate the workload during the transition.
>
> Consider the costs and timelines associated with converting an existing
> base of SAS code that has perhaps gone through a review and validation
> process. What will it take to replicate that functionality in R with the
> same level of reliability? What methodological issues will you face in
> the transition from SAS to R, given the differing philosophies? How long
> will it take, who will do it and what other tasks or projects may be
> impacted during the transition?
>
> In some environments (eg. Big Pharma), re-training and especially code
> conversion/validation costs alone outweigh the savings of not paying for
> SAS licenses. This is why there is a significant hurdle to using R in
> that environment even though such companies may pay SAS millions of
> dollars per year.
>
> I don't know that there is a one size fits all approach to moving from
> SAS to R. Each operating environment has its own characteristics
> relative to budgets, politics, people and so forth. The points that I
> raise above may be typical but only some may apply to your situation and
> there may be others that I have not raised.
>
> HTH,
>
> Marc Schwartz
>
> ______________________________________________
> [hidden email] 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.
>


--
Frank E Harrell Jr   Professor and Chair           School of Medicine
                      Department of Biostatistics   Vanderbilt University

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Frank Harrell
Department of Biostatistics, Vanderbilt University
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Re: Entire Organization Switching from SAS to R - Any experience?

Jeffrey J. Hallman-2
Hmmm, I sense a story in the offing. Was that an accidental emergency, or one you created?

Frank E Harrell Jr <[hidden email]> writes:
> I differ with Marc in one way.  It is amazing what people can learn when you
> create an emergency for them to do so.
>
> Frank
> --
> Frank E Harrell Jr   Professor and Chair           School of Medicine
>                      Department of Biostatistics   Vanderbilt University
>

--
Jeff

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Re: Entire Organization Switching from SAS to R - Any experience?

Frank Harrell
Jeffrey J. Hallman wrote:

> Hmmm, I sense a story in the offing. Was that an accidental emergency, or one you created?
>
> Frank E Harrell Jr <[hidden email]> writes:
>> I differ with Marc in one way.  It is amazing what people can learn when you
>> create an emergency for them to do so.
>>
>> Frank
>> --
>> Frank E Harrell Jr   Professor and Chair           School of Medicine
>>                      Department of Biostatistics   Vanderbilt University
>>
>

Lots of little emergencies with good results.
Frank

--
Frank E Harrell Jr   Professor and Chair           School of Medicine
                      Department of Biostatistics   Vanderbilt University

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and provide commented, minimal, self-contained, reproducible code.
Frank Harrell
Department of Biostatistics, Vanderbilt University
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Re: Entire Organization Switching from SAS to R - Any experience?

dave fournier
In reply to this post by Ross Boylan
It is true that R does not offer support for custom likelihood functions
in nonlinear mixed models. However you can switch to R and use
AD Model Builder's random effects module http://admb-project.org
This is freely available software and it is more flexible than
proc nlmixed. I'm sure there are people involved in the project who
would be happy to help.

   Dave




>We use SAS and R here (a biostat department and consulting unit), in
>part because there are some things SAS does that R doesn't.  In
>particular, we use SAS proc nlmixed with custom likelihood functions.  >R
>has similar capability but does not allow custom likelihood; the >authors
>say adding it would be non-trivial.


--
David A. Fournier
P.O. Box 2040,
Sidney, B.C. V8l 3S3
Canada
Phone/FAX 250-655-3364
http://otter-rsch.com

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Re: Entire Organization Switching from SAS to R - Any experience?

Lamke
In reply to this post by Frank Harrell
We've decided not to proceed with the change but the senior management has been alerted with the uprising SAS license cost.  Thank you so much for all the comments!!!  

Frank E Harrell Jr wrote
Jeffrey J. Hallman wrote:
> Hmmm, I sense a story in the offing. Was that an accidental emergency, or one you created?
>
> Frank E Harrell Jr <f.harrell@vanderbilt.edu> writes:
>> I differ with Marc in one way.  It is amazing what people can learn when you
>> create an emergency for them to do so.
>>
>> Frank
>> --
>> Frank E Harrell Jr   Professor and Chair           School of Medicine
>>                      Department of Biostatistics   Vanderbilt University
>>
>

Lots of little emergencies with good results.
Frank

--
Frank E Harrell Jr   Professor and Chair           School of Medicine
                      Department of Biostatistics   Vanderbilt University

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