Question

) Describe the steps involved in a sampling operation.
(b) Distinguish between primary and secondary sampling.
(c) Outline the methods used to reduce a sample to a manageable size.
(d) Why should you prefer dry-ashing to wet-ashing of a food sample such as
cabbage?
(e) How would you prepare a protein free filtrate (PFF)?

Answer 1

Answer:

answer

Explanation:

a) An operational sampling process can be divided into seven steps as given below:

1. Defining the target population.
2. Specifying the sampling frame.
3. Specifying the sampling unit.
4. Selection of the sampling method.
5. Determination of sample size.
6. Specifying the sampling plan.
7. Selecting the sample.

b)Primary data is the type of data that is collected by researchers directly from main sources while secondary data is the data that has already been collected through primary sources and made readily available for researchers to use for their own research.

C)the many ways to reduce sample size, only a few are likely to result in a significant reduction (by 25% or more).

1. Reduce Alpha Level to 10%
2. Reduce Statistical Power to 70%
3. Add an extra ARM (to a crossover study)
4. Use paired tests instead of independent test