The original article is freely available from :
http://www.stata.com/products/stb/journals/stb55.pdf
There are example datasets accompanying this package, you can download
them by typing -findit ipf- click on ipf, than click on "click here to
get" behind ancillary files.
Hope this helps,
Maarten
--- [email protected] wrote:
> I apparently don't have my data in a form that allows stata v 10.1 to
>
> run the ipf function.
>
> I have a dataset of 262 observations coded by 6 variables, all
> categorical and all, hypothetically, independent.
>
> varlist is
> genre
> race
> type
> condition
> fda_cat
> page_size
>
>
> I ran a multiple correspondence analysis (using XLStat) to look at
>
> patterns with and without the binary variable (race). It was
> recommended that I should also run log-linear models on the data.
>
> What form does the data need to be in for stata to perform the ipf
> command? I have tried several forms:
> 1. full spreadsheet data of 262 observations, each observation coded
>
> with string variables. Six variables of interest, range from
> dichotomous choices, three choices, or five choices. None are
> ordinal. All categorical.
> describe
>
> Contains data
> obs: 262
> vars: 6
> size: 14,410 (99.9% of memory free)
>
---------------------------------------------------------------------------------
> storage display value
> variable name type format label variable label
>
---------------------------------------------------------------------------------
> genre str3 %9s
> race byte %8.0g
> type str7 %9s
> condition str28 %28s
> fda_cat str4 %9s
> page_size str4 %9s
>
> 2. multiway contingency (freq) table, where freq counts of 262
> observations were combined into like combinations showing 63 similar
>
> observations (rows). The frequencies (cell counts) for each of the
> 63
> rows ranged from 1 to 35.
>
> Contains data from C:\Documents and Settings\LaVera
> Crawley\Desktop\transformed
> > log linear data.dta
> obs: 63
> vars: 7 14 Aug 2008 20:52
> size: 1,008 (99.9% of memory free)
>
-------------------------------------------------------------------------------
> storage display value
> variable name type format label variable label
>
-------------------------------------------------------------------------------
> genre byte %8.0g
> race byte %8.0g
> type byte %8.0g
> condition byte %8.0g
> fda_cat byte %8.0g
> page_size byte %8.0g
> freq int %8.0g
> ------------------------------------------
>
> Neither form of the data worked. I still get the error r(109) type
> mismatch message as below (despite what linear equation I use - with
>
> or without interaction terms):
> For example:
> . ipf [fw=freq], fit( race+ genre+ type+ condition+ fda_cat+
> page_size)
> Deleting all matrices......
>
> Expansion of the various marginal models
> ----------------------------------------
> marginal model 1 varlist : race
> marginal model 2 varlist : genre
> marginal model 3 varlist : type
> marginal model 4 varlist : condition
> marginal model 5 varlist : fda_cat
> marginal model 6 varlist : page_size
> unique varlist race genre type condition fda_cat page_size
> invalid syntax
> r(198);
>
>
>
>
> *
> * For searches and help try:
> * http://www.stata.com/help.cgi?search
> * http://www.stata.com/support/statalist/faq
> * http://www.ats.ucla.edu/stat/stata/
>
-----------------------------------------
Maarten L. Buis
Department of Social Research Methodology
Vrije Universiteit Amsterdam
Boelelaan 1081
1081 HV Amsterdam
The Netherlands
visiting address:
Buitenveldertselaan 3 (Metropolitan), room Z434
+31 20 5986715
http://home.fsw.vu.nl/m.buis/
-----------------------------------------
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*
* For searches and help try:
* http://www.stata.com/help.cgi?search
* http://www.stata.com/support/statalist/faq
* http://www.ats.ucla.edu/stat/stata/
