Stata 15 help for mi_extract

[MI] mi extract -- Extract original or imputed data from mi data

Syntax

mi extract # [, options]

where 0 <= # <= M

options Description ------------------------------------------------------------------------- clear okay to replace unsaved data in memory

esample(...) rarely specified option esample(varname) ...syntax when # > 0 esample(varname #_e) ...syntax when # = 0; 1 <= #_e <= M -------------------------------------------------------------------------

Menu

Statistics > Multiple imputation

Description

mi extract # replaces the data in memory with the data for m=#. The data are not mi set.

Options

clear specifies that it is okay to replace the data in memory even if the current data have not been saved to disk.

esample(varname [#_e]) is rarely specified. It is for use after mi estimate when the esample(newvar) option was specified to store in newvar the e(sample) for m=1, m=2, ..., m=M. It is now desired to extract the data for one m and for e(sample) set correspondingly.

mi extract #, esample(varname), #>0, is the usual case in this unlikely event. One extracts one of the imputation datasets and redefines e(sample) based on the e(sample) previously stored for m=#.

The odd case is mi extract 0, esample(varname #_e), where #_e>0. One extracts the original data but defines e(sample) based on the e(sample) previously stored for m=#_e.

Specifying the esample() option changes the sort order of the data.

Remarks

If you wanted to give up on mi and just get your original data back, you could type

. mi extract 0

You might do this if you wanted to send your original data to a coworker or you wanted to try a different approach to dealing with the missing values in these data. Whatever the reason, the result is that the original data replace the data in memory. The data are not mi set. Your original mi data remain unchanged.

If you suspected there was something odd about the imputations in m=3, you could type

. mi extract 3

You would then have a dataset in memory that looked just like your original, except the missing values of the imputed and passive variables would be replaced with the imputed and passive values from m=3. The data are not mi set. Your original data remain unchanged.


© Copyright 1996–2018 StataCorp LLC   |   Terms of use   |   Privacy   |   Contact us   |   What's new   |   Site index