منهجية تحديد نوع و حجم العينة في البحوث العلمية

الملخص EN

This paper aims to clarify the scientific methodology to follow in determining the type and size of the sample in the scientific research, where a decision is to choose the size and type of sample which is the most important determinant of the accuracy of the results obtained.

The results show that there are two basic types of samples, the nonrandom sampling (Accidental, Purposive, Quota, snowball), and random sampling (simple, systematic, stratified, cluster), and several factors influence in the choice of the type of sample including: Population characteristics, the required accuracy of the study, study's available budget.

There are two basic methods in determining the sample size, namely: the experimental method it is valid for determining the sample size of any kind (random, non-random) and the statistical method which is specific to only the random sampling