How to xfill (or workaround) to overcome data inconsistencies

[Kathleen Carluzzo]

Hi there, I have a data set with about 50k records with multiple survey records per person. I want to xfill on key variables (demographics and other characteristics). However, there are inconsistencies (e.g., person A completes 3 surveys, one time they live in GA the next time they live in FL, and the third time they don't answer the question). The xfill command won't execute when the data are inconsistent by id. I developed a workaround (reshaping the data to wide and looking across rows to fill using loops) but it's clunky. Is there another way to achieve this? Thanks!

[William Lisowski]

I'm not sure I understand. When I type help xfill the Viewer window tells me the following.

With that said, perhaps you would find the community-contributed fillmissing command useful.

sse describe fillmissing

[Nick Cox]

There is, or used to be, an xfill at www.sealedenvelope.com
but I can’t get Stata to talk to that site.

As I recall xfill replaces missing values by single non-missing values if and only if just one distinct non-missing value is in evidence. That is false for your example and so you need a different rule, which might be copy last non-missing value.

https://www.stata.com/support/faqs/d...issing-values/

is an FAQ.

[William Lisowski]

For what it's worth I just successfully installed xfill from the site in post #2 and confirmed that xfill is not appropriate for this task. The FAQ is authoritative on filling in missings without relying on anything other than base Stata.

. net from https://www.sealedenvelope.com/
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https://www.sealedenvelope.com/
Programs from Sealed Envelope Ltd
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These programs are provided by Sealed Envelope Ltd.
For more details on their use visit www.sealedenvelope.com

PACKAGES you could -net describe-:
    hl                Hosmer-Lemeshow goodness of fit test
    mlogplot2         Extension to mlogplot to handle two-way interaction terms in mlogit
    reformat          Reformat regression output
    rescale           Rescale categorical variables using numbers found in value labels
    time              Convert strings in HH:MM:SS format to elapsed times and back again
    xcount            Count longitudinal data
    xfill             Fill in static variables in longitudinal data
    xtab              Tabulate longitudinal data
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. net describe xfill

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package xfill from https://www.sealedenvelope.com
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TITLE
      Fill in static variables in longitudinal data.

DESCRIPTION/AUTHOR(S)
      xfill 'fills in' missing values of static variables in
      longitudinal datasets. A static variable is one that is constant
      in multiple record data, such as patient gender in a series of
      follow-up visits on the same patient.
      
      Author: Tony Brady, Sealed Envelope Ltd.
      Distribution-Date: 25oct2012

INSTALLATION FILES                                (type net install xfill)
      stata/xfill.ado
      stata/xfill.hlp
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. net install xfill
checking xfill consistency and verifying not already installed...
installing into /Users/lisowskiw/Library/Application Support/Stata/ado/plus/...
installation complete.

.