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Re: st: example about choice experiment datasheet
From
Arne Risa Hole <[email protected]>
To
statalist <[email protected]>
Subject
Re: st: example about choice experiment datasheet
Date
Wed, 5 Dec 2012 21:09:44 +0000
Elisabetta
The short answer is "yes, maybe". The long answer is long enough to
write a whole book about it; see Hensher et al. which I mentioned
earlier and http://elsa.berkeley.edu/books/choice2.html.
Arne
On 4 December 2012 12:12, elisabetta capobianco
<[email protected]> wrote:
> Dear Arne,
> the main concern about the conditional logit model is its assumption
> of independence from
> irrelevant alternatives (IIA). This assumption implies that the
> probability ratio of individuals
> choosing between two alternatives does not depend on the availability
> or attributes of the other
> alternatives.
> I have 4 alternatives for each choice set, so it's important to me to
> surmount the IIA, and it's better using mixlogit than asclogit, isn't
> it?
>
> Thank you,
> elisabetta
>
>
>
> 2012/11/27 Arne Risa Hole <[email protected]>:
>> You are welcome. -mixlogit- implements the same model as -asclogit-
>> but with random coefficients. You should make sure that you understand
>> the differences between the models before moving on to -mixlogit-, as
>> this is a more complicated model.
>>
>> Arne
>>
>> On 27 November 2012 05:31, elisabetta capobianco
>> <[email protected]> wrote:
>>> Dear Arne,
>>> you're my very helpful, thank you so much.
>>> Now i'm trying to use mix logit, I've ridden your article. It seems to
>>> be better than asclogit, because i have different alternatives on N
>>> choices occasion. Is it more correct for my case, isn't it?
>>>
>>> Thank you!
>>>
>>> elisabetta
>>>
>>> 2012/11/26 Arne Risa Hole <[email protected]>:
>>>> This is to be expected; if you found it surprising you need to read
>>>> the -asclogit- manual entry more carefully. Whether it's correct or
>>>> not really depends on what you are trying to do. I would suggest that
>>>> including socio-demographics in your model only makes sense if you
>>>> interact them with the alternative-specific attributes, since your
>>>> alternatives are unlabelled.
>>>>
>>>> Arne
>>>>
>>>> On 26 November 2012 10:43, elisabetta capobianco
>>>> <[email protected]> wrote:
>>>>> Ok Arne,
>>>>> now It's clear and I have had good results.
>>>>> Just a doubt. When I put inside the socio-demographic variables, the
>>>>> output has the four alternatives 1,2,3,4, even if I write nocons.
>>>>> I don't understand the meaning of this output considering that I have
>>>>> unlabelled alternatives.
>>>>> Is however correct this result?
>>>>>
>>>>> Thank you,
>>>>> Elisabetta
>>>>>
>>>>>
>>>>>
>>>>>
>>>>>
>>>>> 2012/11/24 Arne Risa Hole <[email protected]>:
>>>>>> Elisabetta,
>>>>>>
>>>>>> The "case" variable must a unique identifier for each choice. You can
>>>>>> generate it like this
>>>>>>
>>>>>> egen caseid = group(id scenario)
>>>>>>
>>>>>> The "alt" variable should be coded 1,2,3,4,1,2,3,4 etc. (not
>>>>>> 1,2,3,4,5,6,7,8,...).
>>>>>>
>>>>>> Arne
>>>>>>
>>>>>> On 24 November 2012 16:04, elisabetta capobianco
>>>>>> <[email protected]> wrote:
>>>>>>> Thank you Arne, I have taken the book.
>>>>>>> My problem is that I have 16 scenarios for id (n=131) with 4 different
>>>>>>> alternatives for each scenario .
>>>>>>> So in the dataset I have written for each id non 4 alternatives
>>>>>>> (1,2,3,4) but 64 alternatives. Is it correct?
>>>>>>>
>>>>>>>
>>>>>>>
>>>>>>> id scenario alt
>>>>>>> 1 1 1
>>>>>>> 1 1 2
>>>>>>> 1 1 3
>>>>>>> 1 1 4
>>>>>>> 1 2 5(or1?)
>>>>>>> 1 2 6(or2?)
>>>>>>> 1 2 7(or3?)
>>>>>>> 1 2 8 (or4?)
>>>>>>> 1 3 9(or1?)
>>>>>>> .
>>>>>>> .
>>>>>>> .
>>>>>>> .
>>>>>>> .
>>>>>>> 1 16 64
>>>>>>> 2 1 1
>>>>>>> .
>>>>>>> .
>>>>>>> And when I wrote:
>>>>>>> asclogit choice organic price, case(id) alternatives(car) noconst
>>>>>>>
>>>>>>> case is id or scenario? I suppose scenario. But if is scenario I don't
>>>>>>> know how to use id!
>>>>>>> And alternatives are the 64 alternatives?
>>>>>>>
>>>>>>>
>>>>>>> Thank you so much for your help.
>>>>>>>
>>>>>>> elisabetta
>>>>>>>
>>>>>>>
>>>>>>>
>>>>>>>
>>>>>>>
>>>>>>> 2012/11/23 Arne Risa Hole <[email protected]>:
>>>>>>>> Elisabetta
>>>>>>>>
>>>>>>>> I am fairly sure that you can use -asclogit- to do what you want. If
>>>>>>>> you don't want alternative-specific constants you can use the
>>>>>>>> -noconst- option. Modifying the example in the help-file slightly:
>>>>>>>>
>>>>>>>> webuse choice
>>>>>>>> asclogit choice dealer, case(id) alternatives(car) noconst
>>>>>>>>
>>>>>>>> As you can see the only coefficient which is estimated in this case is
>>>>>>>> the one for the dealer attribute, which is analogous to the organic
>>>>>>>> and price attributes in your experiment. In your case the variable
>>>>>>>> that identifies the alternatives for each case ("car" in the example)
>>>>>>>> can simply take the values 1, 2, 3 and 4 since your alternatives are
>>>>>>>> unlabelled.
>>>>>>>>
>>>>>>>> I also recommend taking a look at a basic choice modelling text before
>>>>>>>> proceeding, such as
>>>>>>>> http://books.google.co.uk/books/about/Applied_Choice_Analysis.html?id=8yZrtCCABAgC.
>>>>>>>>
>>>>>>>> Good luck!
>>>>>>>>
>>>>>>>> Arne
>>>>>>>>
>>>>>>>> On 23 November 2012 13:25, elisabetta capobianco
>>>>>>>> <[email protected]> wrote:
>>>>>>>>> I think that asclogit is not the right comand for me.
>>>>>>>>> Because I have 4 unlabeled alternatives, 16 diferrent scenarios with 4
>>>>>>>>> alternatives for 131 individuals. So my indipendent viariables are the
>>>>>>>>> attributes and dipendent variables the utility for each level of
>>>>>>>>> attribute.
>>>>>>>>> I need to know the importance of every level, not of alternatives.
>>>>>>>>> Ex.:n=131
>>>>>>>>> scenario 1) A B C D
>>>>>>>>> organic org no org no org org
>>>>>>>>> price 4 8 4 4
>>>>>>>>> scenario 2) A B C D
>>>>>>>>> organic no org no org org no org
>>>>>>>>> price 12 16 8 8
>>>>>>>>> .
>>>>>>>>> .
>>>>>>>>> .
>>>>>>>>> Perhaps with mixlogit? Because the example is on a specific
>>>>>>>>> alternative, car or bus.
>>>>>>>>> I instead need to know the coefficient of attributes and levels.
>>>>>>>>>
>>>>>>>>> I don't know if I have explained well, I hope!
>>>>>>>>>
>>>>>>>>> e
>>>>>>>>>
>>>>>>>>>
>>>>>>>>>
>>>>>>>>> 2012/11/23 Arne Risa Hole <[email protected]>:
>>>>>>>>>> -help asclogit_postestimation-
>>>>>>>>>>
>>>>>>>>>> Arne
>>>>>>>>>>
>>>>>>>>>> On 23 November 2012 11:05, elisabetta capobianco
>>>>>>>>>> <[email protected]> wrote:
>>>>>>>>>>> Dear Arne,
>>>>>>>>>>> i need to estimate the marginal effect of levels on attributes of my choice.
>>>>>>>>>>> Is it possible?
>>>>>>>>>>> es:
>>>>>>>>>>> about meat:
>>>>>>>>>>> attribute level
>>>>>>>>>>> label organic/not organic
>>>>>>>>>>> origin local abroad
>>>>>>>>>>> prize 4/8
>>>>>>>>>>>
>>>>>>>>>>> I would know the utility for each level of each attribute.
>>>>>>>>>>>
>>>>>>>>>>> Thank you!
>>>>>>>>>>> elisabetta
>>>>>>>>>>>
>>>>>>>>>>>
>>>>>>>>>>>
>>>>>>>>>>> 2012/11/21 elisabetta capobianco <[email protected]>:
>>>>>>>>>>>> Thank you so much Arne!!!
>>>>>>>>>>>> I'm creating the data set and then i'll try to run in Stata!
>>>>>>>>>>>>
>>>>>>>>>>>> Elisabetta
>>>>>>>>>>>>
>>>>>>>>>>>> 2012/11/20 Arne Risa Hole <[email protected]>:
>>>>>>>>>>>>> Elisabetta
>>>>>>>>>>>>>
>>>>>>>>>>>>> -mlogit- is not very useful to model data from choice experiments as
>>>>>>>>>>>>> it does not allow alternative-specific explanatory variables.
>>>>>>>>>>>>> -asclogit- requires your data to be in long form (one row per
>>>>>>>>>>>>> alternative); see -help asclogit- and the first example in the paper I
>>>>>>>>>>>>> mentioned in my last email.
>>>>>>>>>>>>>
>>>>>>>>>>>>> Arne
>>>>>>>>>>>>>
>>>>>>>>>>>>> On 20 November 2012 10:04, elisabetta capobianco
>>>>>>>>>>>>> <[email protected]> wrote:
>>>>>>>>>>>>>> Thank you Arne, I want to use asclogit and mlogit for my choice modelling.
>>>>>>>>>>>>>>
>>>>>>>>>>>>>>
>>>>>>>>>>>>>> 2012/11/19 Arne Risa Hole <[email protected]>:
>>>>>>>>>>>>>>> Elisabetta
>>>>>>>>>>>>>>>
>>>>>>>>>>>>>>> As Jay says the correct data form depends on the estimation command
>>>>>>>>>>>>>>> you are planning to use, so this is a very important piece of
>>>>>>>>>>>>>>> information that you haven't given us. You may find the examples in
>>>>>>>>>>>>>>> http://www.stata-journal.com/article.html?article=st0133 useful.
>>>>>>>>>>>>>>> Generally speaking the best strategy is to import the data into Stata
>>>>>>>>>>>>>>> and then use commands like -reshape- to convert the data into the form
>>>>>>>>>>>>>>> you want, rather than trying to do this in Excel.
>>>>>>>>>>>>>>>
>>>>>>>>>>>>>>> Arne
>>>>>>>>>>>>>>>
>>>>>>>>>>>>>>>> On 19 November 2012 15:51, elisabetta capobianco
>>>>>>>>>>>>>>>> <[email protected]> wrote:
>>>>>>>>>>>>>>>>>
>>>>>>>>>>>>>>>>> Thank you for your answer!
>>>>>>>>>>>>>>>>> I want to do a mixed logit, but I have found a data set on help file
>>>>>>>>>>>>>>>>> with just one choice set. I have 16 choice sets and I don't know how
>>>>>>>>>>>>>>>>> to fil the excel data set.
>>>>>>>>>>>>>>>>>
>>>>>>>>>>>>>>>>>
>>>>>>>>>>>>>>>>>
>>>>>>>>>>>>>>>>> 2012/11/18 JVerkuilen (Gmail) <[email protected]>:
>>>>>>>>>>>>>>>>> > On Sun, Nov 18, 2012 at 4:11 AM, elisabetta capobianco
>>>>>>>>>>>>>>>>> > <[email protected]> wrote:
>>>>>>>>>>>>>>>>> >> Hi, I'm new of statalist and stata!
>>>>>>>>>>>>>>>>> >> I'm working on choice experiment about food preferences in schools.
>>>>>>>>>>>>>>>>> >> I have 4 alternatives unlabelled, 4 attributes and 4 levels, 130
>>>>>>>>>>>>>>>>> >> individuals.
>>>>>>>>>>>>>>>>> >> I have the data base in excel, but before insheet the file in stata
>>>>>>>>>>>>>>>>> >> i'm not sure that i have put the data in the right mode in the excel
>>>>>>>>>>>>>>>>> >> file.
>>>>>>>>>>>>>>>>> >> Have you got an example on a excel datasheet about choice modelling?
>>>>>>>>>>>>>>>>> >> Just an example to understand how to organize my datasheet.
>>>>>>>>>>>>>>>>> >
>>>>>>>>>>>>>>>>> > It depends on what analysis you want to use. -clogit- and procedures
>>>>>>>>>>>>>>>>> > like it that are using alternative-specific predictors use the same
>>>>>>>>>>>>>>>>> > basic format, which is specified in the help file. You can see the
>>>>>>>>>>>>>>>>> > example dataset there. Essentially it is a "long" format like
>>>>>>>>>>>>>>>>> > person-period in a growth model with time-varying covariates.
>>>>>>>>>>>>>>>>> > *
>>>>>>>>>>>>>>>>> > * For searches and help try:
>>>>>>>>>>>>>>>>> > * http://www.stata.com/help.cgi?search
>>>>>>>>>>>>>>>>> > * http://www.stata.com/support/faqs/resources/statalist-faq/
>>>>>>>>>>>>>>>>> > * http://www.ats.ucla.edu/stat/stata/
>>>>>>>>>>>>>>>>>
>>>>>>>>>>>>>>>>>
>>>>>>>>>>>>>>>>>
>>>>>>>>>>>>>>>>> --
>>>>>>>>>>>>>>>>> Rispetta l'ambiente: se non ti è necessario, non stampare questa mail
>>>>>>>>>>>>>>>>>
>>>>>>>>>>>>>>>>>
>>>>>>>>>>>>>>>>>
>>>>>>>>>>>>>>>>> Le informazioni contenute in questa comunicazione e gli
>>>>>>>>>>>>>>>>> eventuali documenti allegati
>>>>>>>>>>>>>>>>>
>>>>>>>>>>>>>>>>> hanno carattere confidenziale e sono a uso esclusivo del
>>>>>>>>>>>>>>>>> destinatario. Nel caso
>>>>>>>>>>>>>>>>>
>>>>>>>>>>>>>>>>> questa comunicazione Vi sia pervenuta per errore, Vi informo
>>>>>>>>>>>>>>>>> che la sua diffusione
>>>>>>>>>>>>>>>>>
>>>>>>>>>>>>>>>>> e riproduzione è contraria alla legge e prego di darmi
>>>>>>>>>>>>>>>>> prontamente avviso
>>>>>>>>>>>>>>>>>
>>>>>>>>>>>>>>>>> e di cancellare quanto ricevuto. Grazie.
>>>>>>>>>>>>>>>>>
>>>>>>>>>>>>>>>>> *
>>>>>>>>>>>>>>>>> * For searches and help try:
>>>>>>>>>>>>>>>>> * http://www.stata.com/help.cgi?search
>>>>>>>>>>>>>>>>> * http://www.stata.com/support/faqs/resources/statalist-faq/
>>>>>>>>>>>>>>>>> * http://www.ats.ucla.edu/stat/stata/
>>>>>>>>>>>>>>>>
>>>>>>>>>>>>>>>>
>>>>>>>>>>>>>>>
>>>>>>>>>>>>>>> *
>>>>>>>>>>>>>>> * For searches and help try:
>>>>>>>>>>>>>>> * http://www.stata.com/help.cgi?search
>>>>>>>>>>>>>>> * http://www.stata.com/support/faqs/resources/statalist-faq/
>>>>>>>>>>>>>>> * http://www.ats.ucla.edu/stat/stata/
>>>>>>>>>>>>>>
>>>>>>>>>>>>>>
>>>>>>>>>>>>>>
>>>>>>>>>>>>>> --
>>>>>>>>>>>>>> Rispetta l'ambiente: se non ti è necessario, non stampare questa mail
>>>>>>>>>>>>>>
>>>>>>>>>>>>>>
>>>>>>>>>>>>>>
>>>>>>>>>>>>>> Le informazioni contenute in questa comunicazione e gli
>>>>>>>>>>>>>> eventuali documenti allegati
>>>>>>>>>>>>>>
>>>>>>>>>>>>>> hanno carattere confidenziale e sono a uso esclusivo del
>>>>>>>>>>>>>> destinatario. Nel caso
>>>>>>>>>>>>>>
>>>>>>>>>>>>>> questa comunicazione Vi sia pervenuta per errore, Vi informo
>>>>>>>>>>>>>> che la sua diffusione
>>>>>>>>>>>>>>
>>>>>>>>>>>>>> e riproduzione è contraria alla legge e prego di darmi
>>>>>>>>>>>>>> prontamente avviso
>>>>>>>>>>>>>>
>>>>>>>>>>>>>> e di cancellare quanto ricevuto. Grazie.
>>>>>>>>>>>>>>
>>>>>>>>>>>>>> *
>>>>>>>>>>>>>> * For searches and help try:
>>>>>>>>>>>>>> * http://www.stata.com/help.cgi?search
>>>>>>>>>>>>>> * http://www.stata.com/support/faqs/resources/statalist-faq/
>>>>>>>>>>>>>> * http://www.ats.ucla.edu/stat/stata/
>>>>>>>>>>>>>
>>>>>>>>>>>>> *
>>>>>>>>>>>>> * For searches and help try:
>>>>>>>>>>>>> * http://www.stata.com/help.cgi?search
>>>>>>>>>>>>> * http://www.stata.com/support/faqs/resources/statalist-faq/
>>>>>>>>>>>>> * http://www.ats.ucla.edu/stat/stata/
>>>>>>>>>>>>
>>>>>>>>>>>>
>>>>>>>>>>>>
>>>>>>>>>>>> --
>>>>>>>>>>>> Rispetta l'ambiente: se non ti è necessario, non stampare questa mail
>>>>>>>>>>>>
>>>>>>>>>>>>
>>>>>>>>>>>>
>>>>>>>>>>>> Le informazioni contenute in questa comunicazione e gli
>>>>>>>>>>>> eventuali documenti allegati
>>>>>>>>>>>>
>>>>>>>>>>>> hanno carattere confidenziale e sono a uso esclusivo del
>>>>>>>>>>>> destinatario. Nel caso
>>>>>>>>>>>>
>>>>>>>>>>>> questa comunicazione Vi sia pervenuta per errore, Vi informo
>>>>>>>>>>>> che la sua diffusione
>>>>>>>>>>>>
>>>>>>>>>>>> e riproduzione è contraria alla legge e prego di darmi
>>>>>>>>>>>> prontamente avviso
>>>>>>>>>>>>
>>>>>>>>>>>> e di cancellare quanto ricevuto. Grazie.
>>>>>>>>>>>
>>>>>>>>>>>
>>>>>>>>>>>
>>>>>>>>>>> --
>>>>>>>>>>> Rispetta l'ambiente: se non ti è necessario, non stampare questa mail
>>>>>>>>>>>
>>>>>>>>>>>
>>>>>>>>>>>
>>>>>>>>>>> Le informazioni contenute in questa comunicazione e gli
>>>>>>>>>>> eventuali documenti allegati
>>>>>>>>>>>
>>>>>>>>>>> hanno carattere confidenziale e sono a uso esclusivo del
>>>>>>>>>>> destinatario. Nel caso
>>>>>>>>>>>
>>>>>>>>>>> questa comunicazione Vi sia pervenuta per errore, Vi informo
>>>>>>>>>>> che la sua diffusione
>>>>>>>>>>>
>>>>>>>>>>> e riproduzione è contraria alla legge e prego di darmi
>>>>>>>>>>> prontamente avviso
>>>>>>>>>>>
>>>>>>>>>>> e di cancellare quanto ricevuto. Grazie.
>>>>>>>>>>>
>>>>>>>>>>> *
>>>>>>>>>>> * For searches and help try:
>>>>>>>>>>> * http://www.stata.com/help.cgi?search
>>>>>>>>>>> * http://www.stata.com/support/faqs/resources/statalist-faq/
>>>>>>>>>>> * http://www.ats.ucla.edu/stat/stata/
>>>>>>>>>>
>>>>>>>>>> *
>>>>>>>>>> * For searches and help try:
>>>>>>>>>> * http://www.stata.com/help.cgi?search
>>>>>>>>>> * http://www.stata.com/support/faqs/resources/statalist-faq/
>>>>>>>>>> * http://www.ats.ucla.edu/stat/stata/
>>>>>>>>>
>>>>>>>>>
>>>>>>>>>
>>>>>>>>> --
>>>>>>>>> Rispetta l'ambiente: se non ti è necessario, non stampare questa mail
>>>>>>>>>
>>>>>>>>>
>>>>>>>>>
>>>>>>>>> Le informazioni contenute in questa comunicazione e gli
>>>>>>>>> eventuali documenti allegati
>>>>>>>>>
>>>>>>>>> hanno carattere confidenziale e sono a uso esclusivo del
>>>>>>>>> destinatario. Nel caso
>>>>>>>>>
>>>>>>>>> questa comunicazione Vi sia pervenuta per errore, Vi informo
>>>>>>>>> che la sua diffusione
>>>>>>>>>
>>>>>>>>> e riproduzione è contraria alla legge e prego di darmi
>>>>>>>>> prontamente avviso
>>>>>>>>>
>>>>>>>>> e di cancellare quanto ricevuto. Grazie.
>>>>>>>>>
>>>>>>>>> *
>>>>>>>>> * For searches and help try:
>>>>>>>>> * http://www.stata.com/help.cgi?search
>>>>>>>>> * http://www.stata.com/support/faqs/resources/statalist-faq/
>>>>>>>>> * http://www.ats.ucla.edu/stat/stata/
>>>>>>>>
>>>>>>>> *
>>>>>>>> * For searches and help try:
>>>>>>>> * http://www.stata.com/help.cgi?search
>>>>>>>> * http://www.stata.com/support/faqs/resources/statalist-faq/
>>>>>>>> * http://www.ats.ucla.edu/stat/stata/
>>>>>>>
>>>>>>>
>>>>>>>
>>>>>>> --
>>>>>>> Rispetta l'ambiente: se non ti è necessario, non stampare questa mail
>>>>>>>
>>>>>>>
>>>>>>>
>>>>>>> Le informazioni contenute in questa comunicazione e gli
>>>>>>> eventuali documenti allegati
>>>>>>>
>>>>>>> hanno carattere confidenziale e sono a uso esclusivo del
>>>>>>> destinatario. Nel caso
>>>>>>>
>>>>>>> questa comunicazione Vi sia pervenuta per errore, Vi informo
>>>>>>> che la sua diffusione
>>>>>>>
>>>>>>> e riproduzione è contraria alla legge e prego di darmi
>>>>>>> prontamente avviso
>>>>>>>
>>>>>>> e di cancellare quanto ricevuto. Grazie.
>>>>>>>
>>>>>>> *
>>>>>>> * For searches and help try:
>>>>>>> * http://www.stata.com/help.cgi?search
>>>>>>> * http://www.stata.com/support/faqs/resources/statalist-faq/
>>>>>>> * http://www.ats.ucla.edu/stat/stata/
>>>>>>
>>>>>> *
>>>>>> * For searches and help try:
>>>>>> * http://www.stata.com/help.cgi?search
>>>>>> * http://www.stata.com/support/faqs/resources/statalist-faq/
>>>>>> * http://www.ats.ucla.edu/stat/stata/
>>>>>
>>>>>
>>>>>
>>>>> --
>>>>> Rispetta l'ambiente: se non ti è necessario, non stampare questa mail
>>>>>
>>>>>
>>>>>
>>>>> Le informazioni contenute in questa comunicazione e gli
>>>>> eventuali documenti allegati
>>>>>
>>>>> hanno carattere confidenziale e sono a uso esclusivo del
>>>>> destinatario. Nel caso
>>>>>
>>>>> questa comunicazione Vi sia pervenuta per errore, Vi informo
>>>>> che la sua diffusione
>>>>>
>>>>> e riproduzione è contraria alla legge e prego di darmi
>>>>> prontamente avviso
>>>>>
>>>>> e di cancellare quanto ricevuto. Grazie.
>>>>>
>>>>> *
>>>>> * For searches and help try:
>>>>> * http://www.stata.com/help.cgi?search
>>>>> * http://www.stata.com/support/faqs/resources/statalist-faq/
>>>>> * http://www.ats.ucla.edu/stat/stata/
>>>>
>>>> *
>>>> * For searches and help try:
>>>> * http://www.stata.com/help.cgi?search
>>>> * http://www.stata.com/support/faqs/resources/statalist-faq/
>>>> * http://www.ats.ucla.edu/stat/stata/
>>>
>>>
>>>
>>> --
>>> Rispetta l'ambiente: se non ti è necessario, non stampare questa mail
>>>
>>>
>>>
>>> Le informazioni contenute in questa comunicazione e gli
>>> eventuali documenti allegati
>>>
>>> hanno carattere confidenziale e sono a uso esclusivo del
>>> destinatario. Nel caso
>>>
>>> questa comunicazione Vi sia pervenuta per errore, Vi informo
>>> che la sua diffusione
>>>
>>> e riproduzione è contraria alla legge e prego di darmi
>>> prontamente avviso
>>>
>>> e di cancellare quanto ricevuto. Grazie.
>>>
>>> *
>>> * For searches and help try:
>>> * http://www.stata.com/help.cgi?search
>>> * http://www.stata.com/support/faqs/resources/statalist-faq/
>>> * http://www.ats.ucla.edu/stat/stata/
>>
>> *
>> * For searches and help try:
>> * http://www.stata.com/help.cgi?search
>> * http://www.stata.com/support/faqs/resources/statalist-faq/
>> * http://www.ats.ucla.edu/stat/stata/
>
>
>
> --
> Rispetta l'ambiente: se non ti è necessario, non stampare questa mail
>
>
>
> Le informazioni contenute in questa comunicazione e gli
> eventuali documenti allegati
>
> hanno carattere confidenziale e sono a uso esclusivo del
> destinatario. Nel caso
>
> questa comunicazione Vi sia pervenuta per errore, Vi informo
> che la sua diffusione
>
> e riproduzione è contraria alla legge e prego di darmi
> prontamente avviso
>
> e di cancellare quanto ricevuto. Grazie.
>
> *
> * For searches and help try:
> * http://www.stata.com/help.cgi?search
> * http://www.stata.com/support/faqs/resources/statalist-faq/
> * http://www.ats.ucla.edu/stat/stata/
*
* For searches and help try:
* http://www.stata.com/help.cgi?search
* http://www.stata.com/support/faqs/resources/statalist-faq/
* http://www.ats.ucla.edu/stat/stata/