Statistics - 1.3 Simple Random Sampling
What is a frame?
A frame lists all the individuals in a population. For example, a list of all registered voters in a particular precinct might be a frame. The frame is a list of the individuals in the population being studied. If the population of interest is all the students at a school, the frame would be a list of all the students currently attending that school.
What does it mean when sampling is done without replacement?
The population is not changed when a sample is taken from it. When sampling without replacement, once an individual is selected, the individual is removed from the possible choices for that sample and cannot be chosen again.
Define simple random sampling.
The process of obtaining a simple random sample requires more though than just "using chance." A sample of size n from a population of size N is obtained through simple random sampling if every possible sample of size n has an equally likely chance of occurring. The sample is then called a simple random sample.