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Table of Contents

  1. Topic pack - Marketing - introduction
  2. 4.1 The role of marketing - notes
  3. 4.1 The role of marketing - questions
  4. 4.2 Marketing Planning - notes
    1. Marketing planning
    2. The marketing mix
    3. The Total Product Concept
    4. Ethics of marketing
    5. Marketing audit
    6. Porter's five forces
    7. Porter's five forces - activities
    8. Marketing objectives
    9. Market research - introduction
    10. The role of market research
    11. Primary and secondary research
    12. Primary research - information gathering techniques
    13. Observations - case studies
    14. Group-based market research
    15. Market research - summary
    16. Questionnaires
    17. Sampling
    18. Methods of sampling - introduction
    19. Main methods of sampling
    20. Sampling errors
    21. Market segmentation
    22. Consumer Profiles
    23. Types of segments
    24. Demographic segmentation
    25. Psychographic segmentation
    26. Psychographic segmentation - case study
    27. Geographic segmentation
    28. Industrial markets
    29. Targeting
    30. Positioning
    31. Corporate image
    32. Position/perception maps
    33. Unique selling point/proposition USP
    34. Marketing strategies and tactics
    35. Sales forecasting
    36. Qualitative forecasting/data
    37. Forecasting and correlation
    38. Forecasting techniques
    39. Constructing time-series analysis
    40. Moving average
    41. Four point moving average - worked example
    42. Identifying the seasonal variation
  5. 4.2 Marketing planning - questions
  6. 4.3 Product introduction - notes
  7. 4.3 Product - questions
  8. 4.3 Product - simulations and activities
  9. 4.4 Price - notes
  10. 4.4 Price - questions
  11. 4.4 Price - simulations and activities
  12. 4.4 Promotion - notes
  13. 4.5 Promotion - questions
  14. 4.6 Place (distribution) - notes
  15. 4.7 International marketing - notes
  16. 4.7 International marketing - questions
  17. 4.8 E-commerce - notes
  18. 4.8 E-commerce - questions
  19. Printable version

Sampling errors


Two forms of error can creep in when samples are being prepared, and conclusions drawn from the results. These can be considered as bias and statistical.

  • sampling_error_sBias - this is where external effects influence the result. The selection of who makes up the sample may be biased in favour of friends, for instance. The form of the questions may induce a particular answer, and so also introduce bias.
  • Statistical sampling error - even with no bias, there will be error. No two samples will give the same result (except by fluke.) Thus there will be random variations from sample to sample, and between sample and population. Sampling error is the combination of the 'within sample' error and the 'between sample and population' error. Luckily you will not have to work it out.

This is all summed up using confidence limits and standard error. The important thing to remember is that results will not be fully accurate using a sample. However, an estimate of the error or accuracy is possible knowing the sample size and the experimental method.

Is a sample reliable?

To be of use to a firm, results should reflect the intentions of the total population. This is quite an ambitious target. Sampling errors will almost certainly arise and we need to be aware of these. Most researchers accept that two types of error occur most regularly. These are those directly related to the sample and those, which are not.

Think carefully about you think could cause each of these types of error, and then follow the links below to compare your notes with ours.

Errors related to the sample

Errors not related to the sample