I'm looking at an example where a poll of different salaries was conducted to estimate the average salary of a region in Canada. Would this be descriptive or inferential?
The poll of different salaries conducted would on its own be descriptive, but since it is being expanded to estimate the average salary of a region of Canada, the estimation would become inferential.
A descriptive study of a poll or data set uses brief coefficients to describe the data which can comprise either a small sample or the entire data set.
If the results of the study were to be expanded to accommodate a larger population or data set, the values from the descriptive poll would be inferred to meet the needs of the larger set. An inferred study may need a different approach to data collection to that of a descriptive poll.
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