{smcl}
{* 04.03.2001, help to version 1.1 of the program}
{hline}
help for {hi:labelmiss}{right: Stas Kolenikov, skolenik@unc.edu}
{hline}
{title:Label the missing data}
{p 8 16}{cmd:labelmiss} [{it:varlist}] {it:mval} "{it:text}" [ {it:mval} "{it:text}" ...]
, modify
{p}{hi:labelmiss} changes the labels of the missing data for
selected variables.
{it:mval} is one of the missing values, either the system missing value {hi:.}
or the extended missing values {hi:.a}, {hi:.b}, etc.
{title:Options}
{p 0 4}
{hi:modify}
allows Stata to overwrite the existing label, thus indicating your understanding
that the labels are going to be modified. It is not optional. If you want to
be able to recover your original labels, or you would want to define differential
labels for different variables, see {help label}, and {hi:label save}, in particular.
{title:Example}
{p}Suppose we have the data in the following form:
{com}. li id obsw cluster x1-x3 in 1/12
{txt}
{c TLC}{hline 6}{c -}{hline 11}{c -}{hline 9}{c -}{hline 9}{c -}{hline 12}{c -}{hline 12}{c TRC}
{c |} {res} id obsw cluster x1 x2 x3 {txt}{c |}
{c LT}{hline 6}{c -}{hline 11}{c -}{hline 9}{c -}{hline 9}{c -}{hline 12}{c -}{hline 12}{c RT}
1. {c |} {res}1001 13.823839 1 Yes N/A Refused {txt}{c |}
2. {c |} {res}1002 12.876063 1 Yes Yes Yes {txt}{c |}
3. {c |} {res}1003 16.9282 1 Yes Yes Don't know {txt}{c |}
4. {c |} {res}1004 16.752894 1 Yes Yes Refused {txt}{c |}
5. {c |} {res}1005 13.399568 1 No Don't know No {txt}{c |}
{c LT}{hline 6}{c -}{hline 11}{c -}{hline 9}{c -}{hline 9}{c -}{hline 12}{c -}{hline 12}{c RT}
6. {c |} {res}1006 14.806043 1 Refused Yes No {txt}{c |}
7. {c |} {res}1007 13.447599 1 Yes Yes No {txt}{c |}
8. {c |} {res}1008 18.986893 1 No Don't know Don't know {txt}{c |}
9. {c |} {res}1009 12.729379 1 No Refused No {txt}{c |}
10. {c |} {res}1010 13.667414 1 No No Refused {txt}{c |}
{c LT}{hline 6}{c -}{hline 11}{c -}{hline 9}{c -}{hline 9}{c -}{hline 12}{c -}{hline 12}{c RT}
11. {c |} {res}1011 13.124903 1 No Yes Yes {txt}{c |}
12. {c |} {res}1012 13.391117 1 No Don't know No {txt}{c |}
{c BLC}{hline 6}{c -}{hline 11}{c -}{hline 9}{c -}{hline 9}{c -}{hline 12}{c -}{hline 12}{c BRC}
. li id obsw cluster x1-x3 in 1/12, nolab
{txt}
{c TLC}{hline 6}{c -}{hline 11}{c -}{hline 9}{c -}{hline 4}{c -}{hline 4}{c -}{hline 4}{c TRC}
{c |} {res} id obsw cluster x1 x2 x3 {txt}{c |}
{c LT}{hline 6}{c -}{hline 11}{c -}{hline 9}{c -}{hline 4}{c -}{hline 4}{c -}{hline 4}{c RT}
1. {c |} {res}1001 13.823839 1 1 8 7 {txt}{c |}
2. {c |} {res}1002 12.876063 1 1 1 1 {txt}{c |}
3. {c |} {res}1003 16.9282 1 1 1 9 {txt}{c |}
4. {c |} {res}1004 16.752894 1 1 1 7 {txt}{c |}
5. {c |} {res}1005 13.399568 1 2 9 2 {txt}{c |}
{c LT}{hline 6}{c -}{hline 11}{c -}{hline 9}{c -}{hline 4}{c -}{hline 4}{c -}{hline 4}{c RT}
6. {c |} {res}1006 14.806043 1 7 1 2 {txt}{c |}
7. {c |} {res}1007 13.447599 1 1 1 2 {txt}{c |}
8. {c |} {res}1008 18.986893 1 2 9 9 {txt}{c |}
9. {c |} {res}1009 12.729379 1 2 7 2 {txt}{c |}
10. {c |} {res}1010 13.667414 1 2 2 7 {txt}{c |}
{c LT}{hline 6}{c -}{hline 11}{c -}{hline 9}{c -}{hline 4}{c -}{hline 4}{c -}{hline 4}{c RT}
11. {c |} {res}1011 13.124903 1 2 1 1 {txt}{c |}
12. {c |} {res}1012 13.391117 1 2 9 2 {txt}{c |}
{c BLC}{hline 6}{c -}{hline 11}{c -}{hline 9}{c -}{hline 4}{c -}{hline 4}{c -}{hline 4}{c BRC}
. lab li yesno
{txt}yesno:
{res} 1 Yes
2 No
7 Refused
8 N/A
9 Don't know
{txt}
{p}You want to convert your data to missing values, so that you can smoothly run
your analyses, but you don't want to lose your information on what the particular missing data means.
If you {help:mvdecode} your data, your labels are lost:
{com}. mvdecode x* , mv(7 = .a \ 8 = .b \ 9 = .c )
{txt}x1:{res}{col 15}1{txt} missing value generated
x2:{res}{col 15}5{txt} missing values generated
x3:{res}{col 15}5{txt} missing values generated
{com}. li id obsw cluster x1-x3 in 1/12
{txt}
{c TLC}{hline 6}{c -}{hline 11}{c -}{hline 9}{c -}{hline 5}{c -}{hline 5}{c -}{hline 5}{c TRC}
{c |} {res} id obsw cluster x1 x2 x3 {txt}{c |}
{c LT}{hline 6}{c -}{hline 11}{c -}{hline 9}{c -}{hline 5}{c -}{hline 5}{c -}{hline 5}{c RT}
1. {c |} {res}1001 13.823839 1 Yes .b .a {txt}{c |}
2. {c |} {res}1002 12.876063 1 Yes Yes Yes {txt}{c |}
3. {c |} {res}1003 16.9282 1 Yes Yes .c {txt}{c |}
4. {c |} {res}1004 16.752894 1 Yes Yes .a {txt}{c |}
5. {c |} {res}1005 13.399568 1 No .c No {txt}{c |}
{c LT}{hline 6}{c -}{hline 11}{c -}{hline 9}{c -}{hline 5}{c -}{hline 5}{c -}{hline 5}{c RT}
6. {c |} {res}1006 14.806043 1 .a Yes No {txt}{c |}
7. {c |} {res}1007 13.447599 1 Yes Yes No {txt}{c |}
8. {c |} {res}1008 18.986893 1 No .c .c {txt}{c |}
9. {c |} {res}1009 12.729379 1 No .a No {txt}{c |}
10. {c |} {res}1010 13.667414 1 No No .a {txt}{c |}
{c LT}{hline 6}{c -}{hline 11}{c -}{hline 9}{c -}{hline 5}{c -}{hline 5}{c -}{hline 5}{c RT}
11. {c |} {res}1011 13.124903 1 No Yes Yes {txt}{c |}
12. {c |} {res}1012 13.391117 1 No .c No {txt}{c |}
{c BLC}{hline 6}{c -}{hline 11}{c -}{hline 9}{c -}{hline 5}{c -}{hline 5}{c -}{hline 5}{c BRC}
{p}Here's how {hi:labelmiss} fixes it:
{com}. labelmiss .a "Refused" .b "N/A" .c "Don't know" , modify
{txt}
{com}. li id obsw cluster x1-x3 in 1/12
{txt}
{c TLC}{hline 6}{c -}{hline 11}{c -}{hline 9}{c -}{hline 9}{c -}{hline 12}{c -}{hline 12}{c TRC}
{c |} {res} id obsw cluster x1 x2 x3 {txt}{c |}
{c LT}{hline 6}{c -}{hline 11}{c -}{hline 9}{c -}{hline 9}{c -}{hline 12}{c -}{hline 12}{c RT}
1. {c |} {res}1001 13.823839 1 Yes N/A Refused {txt}{c |}
2. {c |} {res}1002 12.876063 1 Yes Yes Yes {txt}{c |}
3. {c |} {res}1003 16.9282 1 Yes Yes Don't know {txt}{c |}
4. {c |} {res}1004 16.752894 1 Yes Yes Refused {txt}{c |}
5. {c |} {res}1005 13.399568 1 No Don't know No {txt}{c |}
{c LT}{hline 6}{c -}{hline 11}{c -}{hline 9}{c -}{hline 9}{c -}{hline 12}{c -}{hline 12}{c RT}
6. {c |} {res}1006 14.806043 1 Refused Yes No {txt}{c |}
7. {c |} {res}1007 13.447599 1 Yes Yes No {txt}{c |}
8. {c |} {res}1008 18.986893 1 No Don't know Don't know {txt}{c |}
9. {c |} {res}1009 12.729379 1 No Refused No {txt}{c |}
10. {c |} {res}1010 13.667414 1 No No Refused {txt}{c |}
{c LT}{hline 6}{c -}{hline 11}{c -}{hline 9}{c -}{hline 9}{c -}{hline 12}{c -}{hline 12}{c RT}
11. {c |} {res}1011 13.124903 1 No Yes Yes {txt}{c |}
12. {c |} {res}1012 13.391117 1 No Don't know No {txt}{c |}
{c BLC}{hline 6}{c -}{hline 11}{c -}{hline 9}{c -}{hline 9}{c -}{hline 12}{c -}{hline 12}{c BRC}
{com}. lab li yesno
{txt}yesno:
{res} 1 Yes
2 No
7 Refused
8 N/A
9 Don't know
.a Refused
.b N/A
.c Don't know
{txt}
{p}We have relabeled all the data, and the variables like {res:id}, {res:cluster} and {res:obsw}
have received the default label {hi:misslab}:
{com}. d id obsw cluster x1-x3
{txt}storage display value
variable name type format label variable label
{hline 79}
{res}id {txt} int %10.0g misslab {res}Personal ID
obsw {txt} double %10.0g misslab {res}Ultimate weight
cluster {txt} byte %10.0g misslab {res}PSU
x1 {txt} byte %10.0g yesno {res}Item 1
x2 {txt} byte %10.0g yesno {res}Item 2
x3 {txt} byte %10.0g yesno {res}Item 3
{txt}
{p}To get rid of this probably undesirable effect, we should have specified
{com}. labelmiss x* .a "Refused" .b "N/A" .c "Don't know" , modify{txt}
{p}Most of the time, the variables that you may want to leave untouched
are in the beginning of the data set. If they are not, you can move them
forward with {help order}. Also, if you want to keep the order of the
variables, modfiy most of your variables, and leave some intact, you
can use {help dellist} from Nick J. Cox's {help listutil} suite of
list utilities:
{com}. unab mylist : _all
. dellist mylist , delete(id cluster obsw) exact
. labelmiss `mylist' .a "Refused" .b "N/A" .c "Don't know" , modify{txt}
{title:Author}
{p}Stas Kolenikov, {browse "mailto:skolenik@unc.edu":skolenik@unc.edu}
{title:See also}
{p}{hi:Online}: help for {help missing}, {help label}, {help mvdecode}