Phân tích kinh doanh UEH - CREATING AND EDITING A DATA FILE của thầy Nguyễn Văn Dũng

CREATING AND EDITING A DATA FILE Nguyen Van Dung Ph.D. 1. Creating and Editing a Data File 1. Creating and Editing a Data File 1. Creating and Editing a Data File 1. Creating and Editing a Data File 1.1 Name 1. Creating and Editing a Data File ▪ Each variable name you use must adhere to the following rules: ▪ Each variable may be any length but shorter than 10 characters is usually desirable. ▪ It must begin with a letter, but after that any letters, numbers, a period, or the symbols @, #, _, or $ may be used. However, the name may not end with a period. ▪ All variable names must be unique; duplicates are not allowed. ▪ Variable names are not sensitive to upper or lower case. ID, Id, and id are all identical to SPSS. ▪ Because they have a unique meaning in SPSS, certain variable names may not be used, including: all, ne, eq, to, le, lt, by, or, gt, and, not, ge, and with 1. Creating and Editing a Data File 1.2 Type 1. Creating and Editing a Data File ▪ Most of variables will be numeric 🡺 default setting. ▪ Two nonnumeric variables in the grades.sav file, lastname and firstname. For those two variables you will click on the grayed box to select String. ▪ A variable that contains letters (rather than only numbers) is called a string variable. String variables may contain numbers (e.g., type2, JonesIII) or even consist of numbers, but SPSS treats strings as nonnumeric, and only a very limited number of operations may be conducted with strings as variables. ▪ Screen 3.3 🡺 eight different variable types are available. Numeric and String are by far the most frequently used options.