Random Number Generator?


TS Contributor
I found the following...

To generate random variables (RVs): You can generate random variables in SPSS via the COMPUTE command. First set the value of the random number seed (or “starting point”) to 1000 using the RANDOM NUMBER GENERATORS command from the Transform menu. SPSS has a number of random variable functions available to the COMPUTE command, and they all look like this RV.***xx.

Thanks to the above poster. I actually found some instructions online that are very helpful, however I need some help clarify certain steps. I am really hoping someone can help me! I'm using SPSS 17 by the way...

I found instructions online where it says to click on the Transform menu-->Random Number Generator. From here I get a little bit lost and need some clarification.

Under ACTIVE GENERATOR INITIALIZATION I have the option of choosing RANDOM or FIXED VALUE. I don't really understand what the difference is. Can anyone tell me? I just want SPSS to give one random number everytime I click o.k.

Also, Once I set up the ACTIVE GENERATOR INITIALIZATION, the instructions tell me to go to TRANSFORM-->COMPUTE. From here I pretty much understand what to do, except when I get to selecting RND(numexpr). This is suppose to allow the program to select integers (or basically round up). However, in my SPSS17, I don't have this function, I only have RND(1), RND(2) OR RND(3). In order to make my file the same as the instructions I edited the function to just RND. I want to know if this changes anything statistically. I don't really know how this would affect the program's ability to generate random numbers. It works, but I want to know if this screws of the probability of selecting random numbers or some other issue that I am not even thinking of.

I know this sounds confusing so here is the link to the instructions. I would really appreciate it someone could clarify things for me. I am not too skilled in spss: stats.http://bus.utk.edu/stat/spss1/randnos.pdf