There are at least two situations.
Consider the situation where the population consists of a number of sub-populations (strata) such that units within a sub-population are similar to one another but there are much larger differences between units from different sub-populations. In order to ensure that the sample is representative, it may be sensible to use stratified random sampling. The sampling proportion may be a constant proportion or may even be such that the variance in each stratum is similar.
The situation may also arise if the population is widely scattered geographically. Rather than expend time and money travelling all over the place, you could employ cluster sampling. Select a number of clusters of the population and then, within each cluster, carry out a census.
There are many advantages and disadvantages of sampling. These advantages include being able to try what you need before you buy.
Answer is Quota sampling. Its one of the method of non-probability sampling.
1) Simple random sampling 2) Systematic sampling 3) Stratified sampling 4) Cluster sampling 5) Probability proportional to size sampling 6) Matched random sampling 7) Quota sampling 8) Convenience sampling 9) Line-intercept sampling 10) Panel sampling
In a stratified sample, the sampling proportion is the same for each stratum. In a random sample it should be but, due to randomness, need not be.
What is the difference between quota sampling and cluster sampling
Non probability sampling and probability sampling are different because probability sampling uses random samples. Non probability sampling aren't random, but can still be representative of the population as a whole if done correctly.
Non-probability sampling is a type of sampling technique whereby all the units of a population do not have an equal chance of being selected in the sample.it may further be divided intoConvenience: Sampling units are selected as per convenience of the researcherPurposive: The units selected in a sample are selected because they posses some requires characteristic e.g., clinical knowledge etc
help me? i need reference blast hole sampling ? please
Soil sampling
Accidental sampling is a type of nonprobability sampling which involves the sample being drawn from that part of the population which is close to hand. That is, a sample population selected because it is readily available and convenient. The researcher using such a sample cannot scientifically make generalizations about the total population from this sample because it would not be representative enough. For example, if the interviewer was to conduct such a survey at a shopping center early in the morning on a given day, the people that he/she could interview would be limited to those given there at that given time, which would not represent the views of other members of society in such an area, if the survey was to be conducted at different times of day and several times per week. This type of sampling is most useful for pilot testing.
There are many advantages and disadvantages of sampling. These advantages include being able to try what you need before you buy.
The greater the sampling error the greater the uncertainty about the results and therefore the more careful you need to be in the interpretation.
They include: Simple random sampling, Systematic sampling, Stratified sampling, Quota sampling, and Cluster sampling.
Answer is Quota sampling. Its one of the method of non-probability sampling.
Sampling techniques in researching involves to types of sampling. The probability sampling and the non-probability sampling. Simple random is an example of probability sampling.
You are correct; convenience sampling is not random sampling.
1) Simple random sampling 2) Systematic sampling 3) Stratified sampling 4) Cluster sampling 5) Probability proportional to size sampling 6) Matched random sampling 7) Quota sampling 8) Convenience sampling 9) Line-intercept sampling 10) Panel sampling