Question

Probability and non probability method of sampling

Answer 1

Key Differences Between Probability and Non-Probability Sampling

The significant differences between probability and non-probability sampling

1. The sampling technique, in which the subjects of the population get an equal opportunity to be selected as a representative sample, is known as probability sampling. A sampling method in which it is not known that which individual from the population will be chosen as a sample, is called nonprobability sampling.
2. The basis of probability sampling is randomization or chance, so it is also known as Random sampling. On the contrary, in non-probability sampling randomization technique is not applied for selecting a sample. Hence it is considered as Non-random sampling.
3. In probability sampling, the sampler chooses the representative to be part of the sample randomly, whereas, in non-probability sampling, the subject is chosen arbitrarily, to belong to the sample by the researcher.
4. The chances of selection in probability sampling, are fixed and known. As opposed to non-probability sampling, the selection probability is zero, i.e. it is neither specified not known.
5. Probability sampling is used when the research is conclusive in nature. On the other hand, when the research is exploratory, nonprobability sampling should be used.
6. The results generated by probability sampling, are free from bias while the results of non-probability sampling are more or less biased.
7. As the subjects are selected randomly by the researcher in probability sampling, so the extent to which it represents the whole population is higher as compared to the nonprobability sampling. That is why extrapolation of results to the entire population is possible in the probability sampling but not in non-probability sampling.

Probability sampling test hypothesis but nonprobability sampling generates it.

Answer 2

Sampling comes in two forms — probability sampling and non-probability sampling. Probability sampling uses random sampling techniques to create a sample. Non-probability sampling methods use non-random processes such as researcher judgement or convenience sampling.