Crosstab of two variables, specifying a single value for each variable

[Rosa Blau]

Hello Statalist,

I'm sure this is a very simply question for most of you.

I have two variables, Q43 and Q44.

* Example generated by -dataex-. To install: ssc install dataex
clear
input byte Q43
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end
label values Q43 Q43

* Example generated by -dataex-. To install: ssc install dataex
clear
input byte Q44
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end
label values Q44 Q44

Just in case the data example should lead you to believe so, both variables are not just filled with missings, as you can see here

codebook Q43

----------------------------------------------------------------------------------------------------------------
Q43                             In your opinion, what is the IDEAL situation for a young child in a two-parent h
----------------------------------------------------------------------------------------------------------------

                  type:  numeric (byte)
                 label:  Q43

                 range:  [1,99]                       units:  1
         unique values:  4                        missing .:  5,934/7,963

            tabulation:  Freq.   Numeric  Label
                           341         1  Both parents working full time
                           718         2  One parent working full time and
                                          one parent working part time
                           948         3  One parent working full time and
                                          one parent not working outside
                                          the home
                            22        99  Refused
                         5,934         .

codebook Q44

----------------------------------------------------------------------------------------------------------------
Q44                             Which parent do you think should [work part time /not work outside the home] in 
----------------------------------------------------------------------------------------------------------------

                  type:  numeric (byte)
                 label:  Q44

                 range:  [1,99]                       units:  1
         unique values:  4                        missing .:  6,297/7,963

            tabulation:  Freq.   Numeric  Label
                            86         1  The father
                           637         2  The mother
                           937         3  It doesn't matter which parent
                                          {#Q44_Insert2}
                             6        99  Refused
                         6,297         .

Now, I simply would like to have a table of those observations, where Q43=1 and Q44=.

For some reason, none of the commands I know with which I would like to do this are working, specifically tab, list, or count:

. tab Q43==1 if Q44==.
== invalid name
r(198);

. list Q43==1 if Q44==.
== invalid name
r(198);

. count Q43==1 if Q44==.
varlist not allowed
r(101);

I'm also not getting wiser through the help function for any of these commands.

Grateful for any help in overcoming this roadblock.

[Marcos Almeida]

Here's an example:

. input Q1 Q2

            Q1         Q2
  1. . 2
  2. 1 3
  3. 3 2
  4. 1 .
  5. 1 .
  6. 1 .
  7. 1 .
  8. 1 .
  9. 1 .
 10. 1 .
 11. end

. tab1 Q1 Q2 if Q1 ==1 & Q2 ==., missing

-> tabulation of Q1 if Q1 ==1 & Q2 ==. 

         Q1 |      Freq.     Percent        Cum.
------------+-----------------------------------
          1 |          7      100.00      100.00
------------+-----------------------------------
      Total |          7      100.00

-> tabulation of Q2 if Q1 ==1 & Q2 ==. 

         Q2 |      Freq.     Percent        Cum.
------------+-----------------------------------
          . |          7      100.00      100.00
------------+-----------------------------------
      Total |          7      100.00

. tab2 Q1 Q2 if Q1 ==1 & Q2 ==., missing

-> tabulation of Q1 by Q2 if Q1 ==1 & Q2 ==. 

           |     Q2
        Q1 |         . |     Total
-----------+-----------+----------
         1 |         7 |         7 
-----------+-----------+----------
     Total |         7 |         7 

  
.

[Rosa Blau]

Marcos Almeida Thank you so much! Not only does this work, but I get it now.

[Nick Cox]

Why not just

tab Q1 Q2, missing

?

[Rosa Blau]

I wouldn't want to tab all missings for both variables, as each variable has 5000+ missings. Or am I misreading the syntax again?

[Nick Cox]

You should try it! If missing means just system missing, you have at most one extra row and one extra column in the table.