Secondary data (MR, unit 6)

data neither collected by, nor specifically for, the user

always start with secondary research - check what's already known and what to investigate further
collecting secondary data = 'desk research'

THE USE OF SECONDARY DATA

• Backdrop to primary research - journals, existing market reports, press
• Substitute for primary research - primary is very costly, so use cost-benefit analysis
• Technique in itself - some information can only be got through secondary data e.g. trends over time

BENEFITS, RISKS & DANGERS OF USE
Consider...

• who produced it - e.g. bias, trade association may exclude counter interest
• reasons for data being collected
• collection method
• how old data is
• how parameters defined

Advantages:

• cheaper and quicker than primary
• can help: define parameters (hypothesis and sampling), give guidance, assimilate primary with past research

Disadvantages:

• relevance
• cost-benefit analysis
• bias
• accuracy:
• is the raw data available?
• were questionnaires properly constructed?
• large enough sample?
• were field workers supervised?
  
• correct analysis?