Samples selected in a non-probabilistic sampling strategy based on the feasibility or ease of collection. It's a non-random sampling. The data reported refer themselves to units selected according to this strategy. Special instance of selective sampling where no randomisation is performed in extracting the sample but units are selected only on the basis of feasibility or ease of data collection. The subpopulations may or may not be determined on a risk basis. The sampling from each subpopulation cannot be considered proportional to the population