Primary and Secondary Data

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Primary and Secondary Data
Experiment
Survey
Interview
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Objectives of this lesson Primary and Secondary
Data

• Define secondary and primary data
• Describe primary data collection methods
• Describe sampling techniques
• Identify advantages disadvantages of different
  data gathering techniques
• Construct a survey

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Secondary Data

• Data gathered by another source (e.g. research
  study, survey, interview)
• Secondary data is gathered BEFORE primary data.
  WHY?
• Because you want to find out what is already
  known about a subject before you dive into your
  own investigation. WHY?
• Because some of your questions can possibly have
  been already answered by other investigators or
  authors. Why reinvent the wheel?

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Primary Data

• Data never gathered before
• Advantage find data you need to suit your
  purpose
• Disadvantage usually more costly and time
  consuming than collecting secondary data
• Collected after secondary data is collected

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Sampling Techniques

• Population - total group of respondents that the
  researcher wants to study. Populations are too
  costly and time consuming to study in entirety.

Sample - selecting and surveying respondents
(research participants) from the population.
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Sampling Techniques

• A probability sample is one that gives every
  member of the population a known chance of being
  selected.
• simple random sample - anyone
• stratified sample - different groups (ages)
• cluster sample - different areas (cities)
• All are selected randomly.

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Sampling Techniques

• A non-probability sample is an arbitrary
  grouping that limits the use of some statistical
  tests. It is not selected randomly.
• convenience sample - readily available
• quota sample - maintain representation

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Primary Research Methods
Advantages
Disadvantages

• Focus Groups bring together respondents with
  common characteristics
• Observation - actually view respondents
• Experiment - controlled variables and respondent
  groups.
• Non-personal survey on site, telephone, mail,
  fax, computer, panel
• Personal interview - one-on-one survey with
  respondents
• Company records internal document survey
  research

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Constructing the Questionnaire

• Select the correct types of questions
• open ended harder to score but get richer
  information
• closed ended, dichotomous offer two either/or
  responses (true/false yes/no for/against
• multiple choice select one or more than one
• scaled response gather range of values
  (strongly disagree, somewhat disagree, neutral,
  somewhat agree, strongly agree

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1. Have you had any of the following medical
preventive tests/exams?

• _____ mammogram (if a women)
• _____ prostate exam (if a man)
• _____ lung x-ray
• _____ electrocardiogram
• _____ stress test

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2. Do you currently smoke? _____
YES _____ NO
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• Please evaluate the following statement
• I understand the Universitys code of conduct as
  it relates to plagiarism.
• ____ absolutely agree
• ____ somewhat agree
• ____ neutral
• ____ somewhat disagree
• ____ absolutely disagree

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Important characteristics of good questionnaires

• Plan a user-friendly format
• Gather demographic data age, gender, etc., when
  necessary.
• Guarantee anonymity
• Ensure ease of tabulation Scantron forms
• Ask well-phrased and unambiguous questions that
  can be answered
• Develop for completeness get all the data
• Pilot test the instrument

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Assignment

• Prepare a questionnaire (word processed on
  paper) that you utilized to gather the primary
  data for the formal report case.
• The questionnaire will be inserted as an appendix
  at the end of your formal report.
• Remember, you should include on the survey
• an introductory statement about the purpose of
  the survey,
• a motivational reason why customers should take
  it, and
• a reminder to participants that they are taking
  the survey anonymously.
• You should NOT include on the survey
• answer percentages

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Example Questionnaire
purpose of the survey
ensure anonymity
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END