User Sampling Methods :: essays research papers

1Sampling MethodsWhen surveying, for any purpose, it is important to signalise that the results ar only as representative as the survey bailiwicks (the prototype), and as such much academic research has been performed in to techniques for selection, broadly placing them in one of two categories probability sampling and non-probability sampling.In short, with probability sampling the participants atomic number 18 selected by chance. There are dozens of methods of selecting members, using a variety of mathematical techniques, but the key is that each subject has a random, calculable chance of being selected. There is no human noise involved in the selection.MethodCharacteristicsSimple (random) SamplingThe ingest is selected solely at randomStratifiedThe population is first divided in to exclusive subgroups based on some predetermined criteria (e.g. location), then samples are selected at randomProportionate StratifiedAs above, but a smaller group that would otherwise not pr ovide statistically valid results may be oversampled then the results weighted to correct for this. For example, if a cross group is too small to provide a statistically of import sample, more members of that group would be sampled ClusteringThe starting point for the sample is randomised, then assumes that the sample at that point is representative of the region. For example, selecting a path corner, interviewing the first 10 people, and assuming that they are representative of the area dishearten 2 - Probability Sampling MethodsNon-probability samples, however, contain an element of human virgule in the sample selection. Again, there are various methods for the selection, the most communal of which areMethodCharacteristicsQuotaRespondents are preselected to ensure that the sample is representativegoal-directedSubjects are selected as they have some specific characteristic, for example, hold a certain position or job typeConvenienceThe sample is selected by availabilitySnowbal lingContacts provide information about other potentiality respondents ego-selectionRespondents volunteer themselves for selectionJudgementAn expert gives his or her judgement to puddle people for sampleTable 3 - Non-probability Sampling MethodsMost samples use a combination of sample selection methods. For example, quota sampling is often utilize to ensure that a random sample is actually representative of the population.2Survey typesThere are three basic surveying techniques that are suitable for consideration in the projectInterviewTelephoneSelf Administered Survey2.1Interview (face to face)This category includes in-depth interviews, focus groups and projective methods (such as word friendship tests) which are not suitable for use in this project. There are several distinct advantages to this type of survey, such asResponse rank tend to be higher than other methods Ability to reassure the subject about their responses