Business Mathematics and Statistics · Ch 9 — Collection, Classification and Tabulation of Data
Distinguishing Primary from Secondary Data
2
Distinguishing Primary from Secondary Data
The difference between the two types is a standard examination point, and it is clearest set out side by side.
| Basis | Primary data | Secondary data |
|---|---|---|
| Meaning | Collected afresh, first-hand, for the current enquiry | Already collected by others for an earlier purpose, re-used |
| Originality | Original ('first-hand') | Not original ('second-hand') |
| Collected by | The present investigator or their agency | Someone else, earlier |
| Purpose | The present enquiry itself | Some other, earlier enquiry |
| Cost, time and labour | High — costly, slow, needs more effort | Low — cheaper, quicker, less effort |
| Accuracy and reliability | Known and generally more reliable; fits the enquiry exactly | Must be checked for suitability and reliability before use |
| Precautions needed | Care in the actual collection | Care in judging suitability, reliability and adequacy of existing data |
Definition 1Suitability of secondary data
The requirement to check that existing data actually fits the present enquiry's definitions, units, coverage and period …