Sampling is a very important statistical tool used by researchers to find accurate results that represents the complete attributes of population.
Different types of sampling are used for different type of data. For example: probability sampling is used for quantitative data as attributes of such data can easily be generalized to population.
While dealing with the qualitative data, on probabilistic methods of sampling are used because such data represents social attributes. Researchers use generalization, comparability, totalization or transitivity methods for qualitative data.
To understand the learning and teaching relations of minority children in Botswana school, we have to understand the social, cultural and learning environment of such kids. Then the role of teacher and their teaching methods are analyzed.
Researchers like Le Compte, Preissle and Merriam say that population or data units are basics to determine the sampling procedures that are used for sampling.
As per the nature of the analyzing learning and teaching relations of Botswana children, we use purposive sampling strategy to analyze difference between school sites.beacause Purposive sampling strategy helps researchers to understand the issues for study in depth. such criterion based study increases the validity of study as it focuses on every aspect of the data.
Baszanger and Dodier criticize this strategy as this study focuses on single culture while conditions of cultures differ from one culture to an other. They say that researchers own background may influence the validity of this research.
According to Morse, data can be validated when it is more specific and has links with the relevant study. Thus such data can be useful for existing data and further study.