Sample selection
Sampling without replacement
Sample size
Select a sample

Sampling without replacement

Samples are usually selected without relacement. It means that each person can only occur once in a sample. It is not very useful to have a person more than once in the sample, What what you do with such a person? Interview him twice, or copy his questionnaire? It is clear that a sample with duplicate persons contains less information than a sample in which each person is different.

You can draw a simple random sample without replacement with the tool below. Note that each number will have the same probability of being selected in the sample.


Sample size

Before a sample can be drawn, you must first specify the size of the population and the size ofthe sample, In practice, the sample size will usually be a compromise between the required precision and the costs of the survey. Large surveys are expensive but produce precise results. Small surveys are cheap, but estimates will have a larger margin of error.

Specify the size of the population and sample below:

Population size:
Sample size:

Select a sample

if the population size and sample size have been specified, you can start the selection of the sample by clicking on the button Draw below.

The selected sample will be displayed in a new window. This windows contains the sequence numbers of the selected persons.

You can save the selected sample with the menu option File | Save as. You can print the sample with File | Print.

Start the selection of the sample: