DATA COLLECTION

1. Determined

1.1. Target population

1.1.1. Sample

1.1.1.1. Variables

1.1.1.1.1. Scale of measurement

2. Types

2.1. Descriptive: to describe the population

2.1.1. Comparative: to compare the population

2.1.1.1. Experimental: to investigate the relationship between variables

2.1.1.1.1. Observation: to collects data without reaching to the objects

3. Sources of Data

3.1. Primary: Normally match to our need and appropriate for longitudinal studies.

3.1.1. Secondary: Commonly not match to our need and same some costs