st: Problem with -reshape- and value labels

[Clyde Schechter <cschecht@aecom.yu.edu>]

I am having a problem whereby I start out with a data set that has a 
number of variables with some different value labels.  They 
variables' names share a common prefix, and when I reshape the data 
to long format, it seems that the value label assigned to the _last_ 
of the variables is carried to the new variable that equals the 
common prefix.  For example:

. des

Contains data
  obs:            10
 vars:             7
 size:           160 (99.9% of memory free)
-----------------------------------------------------------------------------------------------------------
              storage  display     value
variable name   type   format      label      variable label
-----------------------------------------------------------------------------------------------------------
seq             int    %8.0g
resp1           byte   %8.0g       boolean    1 resp
resp2           byte   %8.0g       boolean    2 resp
resp3           byte   %8.0g       boolean    3 resp
resp4           byte   %8.0g       boolean    4 resp
resp5           byte   %8.0g       boolean    5 resp
resp6           byte   %8.0g       other      6 resp
-----------------------------------------------------------------------------------------------------------
Sorted by:  seq

. reshape long resp, i(seq) j(item)
(note: j = 1 2 3 4 5 6)

Data                               wide   ->   long
-----------------------------------------------------------------------------
Number of obs.                       10   ->      60
Number of variables                   7   ->       3
j variable (6 values)                     ->   item
xij variables:
                  resp1 resp2 ... resp6   ->   resp
-----------------------------------------------------------------------------

. des

Contains data
  obs:            60
 vars:             3
 size:           720 (99.9% of memory free)
-----------------------------------------------------------------------------------------------------------
              storage  display     value
variable name   type   format      label      variable label
-----------------------------------------------------------------------------------------------------------
seq             int    %8.0g
item            byte   %9.0g
resp            byte   %8.0g       other
-----------------------------------------------------------------------------------------------------------
Sorted by:  seq  item
     Note:  dataset has changed since last saved

But the real problem arises further on:

<snip> do stuff to resp variable

<end snip>

. reshape wide
(note: j = 1 2 3 4 5 6)

Data                               long   ->   wide
-----------------------------------------------------------------------------
Number of obs.                       60   ->      10
Number of variables                   3   ->       7
j variable (6 values)              item   ->   (dropped)
xij variables:
                                   resp   ->   resp1 resp2 ... resp6
-----------------------------------------------------------------------------

. des

Contains data
  obs:            10
 vars:             7
 size:           160 (99.9% of memory free)
-----------------------------------------------------------------------------------------------------------
              storage  display     value
variable name   type   format      label      variable label
-----------------------------------------------------------------------------------------------------------
seq             int    %8.0g
resp1           byte   %8.0g       other      1 resp
resp2           byte   %8.0g       other      2 resp
resp3           byte   %8.0g       other      3 resp
resp4           byte   %8.0g       other      4 resp
resp5           byte   %8.0g       other      5 resp
resp6           byte   %8.0g       other      6 resp
-----------------------------------------------------------------------------------------------------------
Sorted by:  seq

Notice now that the value label "other" has been spread on to all of 
the variables resp1-resp5 that originally had value label "boolean."

This then raises problems because I later attempt to select a group 
of variables for some further analyses with:

ds, has(vallabel boolean)

which now comes up empty.

I can't get around this by just moving the resp6 variable earlier in 
the data set: its unique value label gets singled out for the 
long-format prefix-named variable regardless of where it physically 
is in the data set.  In fact, the work around seems to be to rename 
one of the "boolean" labeled variables to have a name that is 
alphabetically last.

That would keep the "boolean" label from getting wiped out, but then 
it results in all the variables being so labeled when I reshape back 
to wide, so the -ds- command then traps variables that should be 
excluded from further analysis.  Is there anyway to have -reshape- 
restore the original labels?

(Evidently I can just relabel them by hand in this example, but the 
real data set I'm working with has several dozen such variables, so 
this starts to get impractical.)

I checked the -reshape- section of the manual and I find no mention 
of anything about how value labels are handled.

Any help would be appreciated.  Thanks in advance.

Clyde Schechter
Albert Einstein College of Medicine
Bronx, New York, USA

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