 Sampling refers to a group of people taking part in a market research survey selected to be representative of the target market overall  Types of sampling › Random › Quota › Stratified › Cluster › Snowballing  Sampling errors refer to errors in research caused by using a sample for data collection rather than the whole target population

 Each member of the population has an equal chance of being included in the sample Everyone has an equal chance – this might reduce bias Quite easy  Could select people who are not part of target group  May not get representative results

 Each Population is segmented into mutually exclusive sub-groups (e.g. male/female). From these groups, a certain number of people are selected to part of the sample Sample can be obtained quickly and cheaply More reliable than random sampling  Not always representative of the population  Sampling errors could occur because not everyone has an equal chance to be sampled

 Involves segmentation (segments = strata). Participants are chosen from each group but in a way that is proportional to the population Samples are more representative of target market  Can be difficult to select strata

 If the population is too far spread, market researchers will sample indiviudal groups, known as clusters. i.e. from just a few lcoations Quick and easy, relatively cheap  Bias and sampling errors (sometimes people living in same area share similar views/characteristics)  May not get representative results

 The first respondent refers a friend…who then refers another friend…who then refers another friend…etc Cheap Easy to get contact details of respondents  Tends to be very biased

 As with all things, there are limitations to sampling. The main drawback of sampling is errors. We can categorize these errors into non-sampling errors and sampling errors. › Differentiate between the two types of errors › Explain why sampling errors could occur