3.1.15 Reliability of samples
The reliability of samples can be tested in the following ways:
1. Different samples of the same size should be taken from the same universe and their results be compared. If results are similar, the sample will be reliable.
2. If the measurements of the universe are known, then they should be compared with the measurements of the sample. In case of similarity of measurements, the sample will be reliable.
3. Sub-samples should be taken from the sample drawn. If the results of sample and sub-samples are similarity, the sample may be considered as reliable.