A SAMPLING TECHNIQUE is a procedure used to determine the indiciduals or members of a sample. It may be a probability or non-probability sampling technique.

Probability Sampling - each member ir element of the population has an equal chance of being selected as members of the sample

There are five Probability Sampling Techniques:

1. Random Sampling - basic type of probability sampling; each individual in the populatiom has an equal chance of being drawn into the sample; can be done in two ways; a complete list of the members of the population is required
a. Lottery Method - each member of the population may be assigned a number, the numbers (or the names of the members of the population) are written on pieces of paper, folded then drawn randomly
b. Table of Random Numbers
2. Systematic Sampling - select a random starting point, then draw successuve elements from the population; ie every nth element of the population is picked
3. Stratified Random Sampling - the elements of a population is divided into categories or sub-populations then members of the sample are drawb or selected proportionally from each subpopulation
4. Cluster Sampling or Area Sampling - groups or clusters instead of individuals are randomly chosen; members of the sample are selected by group and then a sample of elements is selected from each group or cluster randomly
5. Multi-Stage Sampling - combination of several sampling techniques; usually used by researchers who are interested in studying a very large population

Non-Probability Sampling or Subjective Sampling - members of the samp,e are drawn from the population based on the judgement of the researchers; results are relatively biased; lacks objectivity of selection; not so reliable but convinient and economical

There are three Probability Sampling Techniques:

1. Convinience Sampling - based on what is convinient for the researcher; researcher chooses members of the population who/which are easiest to interview/observe
2. Quota Sampling - proporitons of the various subgroups in the population are determined and the sample is drawn to have the same percentage in it; similar to stratified random sampling but the selection is not done randomly
3. Purposive Sampling - a specific sample of the population is targeted for interview/observation

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