SPSS Data Files
Previous Topic  Next Topic 

Stat/Transfer will read and write SPSS data files from the following platforms:


       Macintosh

       Windows and OS/2

       Unix  HP/Sun/IBM

   

Standard extension: sav



Reading and Writing SPSS Data Files

Long variable names, used in Version 12 and above, are supported.


Long strings, used in Version 13, are read and written.


SPSS 21 gsav compressed files are read.


Reading SPSS Data Files

Stat/Transfer automatically recognizes a file's platform of origin on input.


Stat/Transfer will read both compressed and uncompressed SPSS data files.


Writing SPSS Data Files

On output, Stat/Transfer allows you to choose a file type for Windows and OS2 or a Unix file type either for the general group of HIGH-LOW (Sun, HP, IBM and Macintosh) or LOW-HIGH byte order machines (DEC).


Stat/Transfer always writes compressed files (which on typical survey data are notably smaller).


Value and variable labels are fully supported.


Missing Data

SPSS allows for three numeric missing values.  By default, on input these are recognized by Stat/Transfer.  The default behavior can be changed with the User Missing Values selection of the Options dialog box.


By default (when the option Map to extended (a-z) missing is left unchecked), all user missing values that are selected according the options Use All/Use First/Use none will go to a single missing value which will then be converted to the "system" missing value in the target package ('.' in SAS or Stata, for example).


If the option Map to extended (a-z) missing is checked, user missing values will be mapped, if possible, to extended missing values in formats that support them (SAS, ASCII, or Stata).


If possible, the first letter of the value label will be used as the missing value. For instance, if the value '0' is a user missing value and is labeled as "inapplicable", it will be mapped to '.i'.  This mapping will only occur for missing values that are computed with an equal operator.


If there is no label, or if the missing letter has already been used, the missing value will be mapped sequentially to '.a' -  '.c'.


On output to SPSS, missing values are set to the SPSS system missing value.


Output Variable Types

The output variable type that results from each target variable type is given in the following table:




Target Type

Output Type


byte

int

long

float

double

Number


string

Character


date

Number (formatted as an SPSS date)


time

Number (formatted as an SPSS time) 


date/time

Number (formatted as an SPSS date/time)