1. Types of data
2. Secondary data
3. Sampling methods
2.1 Types of data
Data can be classified as follows:
(a)Primary and secondary data
Primary data – are data collected especially for a specific purpose.
Secondary data – are data which have been collected elsewhere, for some
other purposes, but which can be used or adapted for the
survey being conducted.
(b)Discrete and continuous data
Discrete data – are data which can only be taken on a finite or countable
number of values within a given range.
Continuous data – are data which can take on any value.
(c )Sample and population data
Sample data – are data arising as a result of investigating a sample
Population data – are data arising as a result of investigating the population.