should we always use replacement to estimate population mean when should sampling happen does sampling have to occur before replacing data when to use substitution in regression when should random sampling occur why is it wrong to test with replacement can we sample after a random sampling? why would you need to replace all data after a sample should sampling happen with or without substitution why does sampling happen without replacement? why do we use substitution for sampling do you do a sample without replacement should a random sampling happen without replacement what is mean of random sampling is a population sampling done with or without replacement when should sampling happen when does sampling occur with replacement do i need to replace data when estimating sample mean? should sampling occur with or without replacement in a simple random sample can we do sampling with or without sampling