The Research Methods Knowledge Base - Essay Example

Sampling methods consist majorly of two: (a) Probability sampling and (b) Non-probability sampling. To start with, probability sampling involves random selection and has four methods as follows. Simple random sampling where there is an equal chance of selection for every element. In systematic random sampling, every ninth element is selected while stratified random sampling is one in which the population is divided into segments (Trochim, 2004). Lastly, a cluster sample is where a particular subgroup is randomly chosen to represent the population under study.

In conclusion, non-probability random samples occur due to influence by certain factors. These factors are as follows: Convenience which is easy to find, purposive relating to the purpose intended, snowball sampling where the chosen subject suggests another, and finally quota which involves subgroups chosen to represent a quota of the population to be studied (Tille and Ardilly,187). Sampling advantages are time-saving, economical, easy to adapt, reliable and indispensable. Limitations of sampling or inaccuracy in the results, expensive in terms of time and energy, unsuitable in that not applicable to other areas, and inherent defects in the method.