A complex sample may be multistage, stratified, or clustered.
Many samples also have unequal probabilities of selection, or are drawn from finite populations.
If you are primarily a SPSS or Minitab user, you will want to install the stand-alone version. If you are primarily a SAS user, then you will want to install the SAS-Callable version. The SAS-Callable version is used in conjunction with SAS for Windows. Before you purchase a copy of SAS for your own system, we encourage you to speak with Statistical and Mathematical Services Group about system requirements. Experience has shown us that individual systems and unique software on your computer can interact to affect SAS performance.