General Options
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Ask Permission before Overwriting Files

The option Ask Permission Before Overwriting Files is on by default.  If a file, or a database table exists, you will be prompted for permission before it is overwritten.


If you wish to suppress these warning messages, click on the box to remove the check mark.


Write New, Numeric Variable Names (Vn)

When you go from one format to another, by default Stat/Transfer will create legal variable names for you, based as much as possible on the original names.  In particular, when you transfer from systems such as Paradox or JMP, which allow long variable names with embedded spaces, to older systems which restricts variable names to eight characters, by default Stat/Transfer will truncate for you.  However, these truncated names often have little resemblance to the names you started with.  Stat/Transfer will use the variable names as variable labels, so that your original names are available.


If you check the option Write new, numeric variable names. (Vn), instead of the default variable names, Stat/Transfer will create new variable names of the form V1...VN.  This is chiefly useful when dealing with truncated names.  If your output system supports variable labels, it is sometimes better to check this option and have Stat/Transfer simply create numeric names for your variables.  You can then use the variable labels for the description.


Because this option is likely to be useful only in special circumstances, it reverts to the default between sessions.


Preserve value label tags and sets

Many software packages allow users to assign the same set of value labels to more than one variable. (In SAS, the term for value labels is "user-defined format").  For example, a survey with a list of questions with "Yes" and "No" responses could use the same set of value labels for the variables associated with each of these questions.


If the option Preserve value label tags and sets is checked, the mapping of value label sets to multiple variables will be preserved on output.  If  tags are used in the input file to identify value labels sets, these will be preserved.  Otherwise, tags will be constructed by Stat/Transfer (LABA-LABZ and so on).


If this option is not checked, each labeled variable will have a unique value label set and the tag used to identify the set will be constructed from the name of the variable.


This option is off by default.


Use Doubles

The Use Doubles box can be checked here if you want Stat/Transfer to use doubles when it optimizes your output data set.  By default, this option is on.


Uncheck the Use Doubles option if you need to minimize the size of your output dataset (particularly for Stata) and you know that the precision of measurement of all of your variables is less than eight decimal digits.


Preserve String Widths if Possible


Normally, Stat Transfer will calculate the minimum string width for each variable and use it in the output encoding.  This ensures that the output file will be as small as possible. This option allows you to maintain the input string width.  This is particularly useful when combining different files.


If this option is checked, Stat/Transfer will use the input width will be used as the output width if it can do it without losing data.  More precisely, the variable width will be the minimum of the string width and the input width.  The output can be greater, but not less than the input width.  For plain ASCII data, it will be the same.


Preserve Numeric Widths if Possible


This option is useful if you are reading text data or data which comes from a format which preserves the width originally used to read the data (SPSS is a prime example).  If you are writing text data or want a variable to be formatted with the same width as was present in the input, check this option.  If, after optimization, the variable is wider than the input width, the variable will be widened to prevent loss of data.



Display Obsolete Formats


This is an option designed to reduce clutter on the input and output File Type drop down menus.  Lotus 123 used to have 99% or the spreadsheet market, but we doubt anyone is using it today.  If you would prefer not to see such old friends, check this option, but please remember that it is there, in case some one sends you a file that needs to be dusted off and converted to something more useful.


Seed for Sampling Functions

By default, the sampling functions in WHERE expressions will generate a starting seed randomly, based on the clock time.  This means that each time you run a transfer on a given file you will select a different sample.  If, in contrast, you need a reproducible sample, you can enter a seed for the random sampling process.  The seed should  be a positive  integer in the range of one through 2,147,483,646.

Variable name case conversions

Stat/Transfer always follows the variable-naming rules of the output file type and will convert input names so that they will conform to those rules.  Some older packages require upper case variable names.  Other more modern packages allow mixed case variable names.  Some packages, notably Stata, S-PLUS and R allow mixed case variable names, but are case sensitive.  In these case-sensitive systems, if Stat/Transfer were to move data from an upper-case system and do no case-conversion, the user of the data set would need to always hold down the shift key when typing in variable names.


Stat/Transfer allows you to specify your case conversion preferences for case-insensitive packages as well as case-sensitive packages.


The available options are given in the drop-down menus for both case-sensitive and case-insensitive programs and are:




The default for case-insensitive programs is "Preserve always".


The default for case-sensitive programs is "Preserve if mixed case".  This choice is designed to handle mixed case variable names such as "FamilyIncome".  If both upper and lower case letter are found in a variable name, it will be left untouched.  Otherwise it will be converted to lower case. 


Formats which are considered case-sensitive on output are: Stata, S-PLUS, R, and Matlab. 


Formats that require upper-case variable names are: SAS version six, SAS XPORT, SPSS Portable, SYSTAT, Epi Info, and older xBASE versions such as Clipper and dBASE II.


All other formats are case-insensitive.