EMPIRICAL

= data collected from observation or experiment... doesn't reply on argument or beliefs so open to public scrutiny.

• belief that all knowledge should be devised from sensory experince.
• Objectivity.. without bias.. greatest control

= any component reseacher can replicate the specific study to achieve the same results

• It strenghens the theory, methods and results
• adds confidence 
• confirms validity so able to generalise 

= ability of reseacher to make a justified extension of their conclusions, apply them to other memebers of the target population and other situations

• it validitates theory to find general principles that can apply to all 
• cant always generalise and different cultures, sample used (volunteer, or opportunity)