Idiographic VS Nomothetic

• Idiographic approach is how individuals behave and how they differ- investigates the unique, personal and subjective experience of the individual
• Principle behind the Idiographic approach - all individuals are unique so it only makes sense to study individuals and qualitative method of collecting data employed (in depth) collecting data through: interviews, self-reports, case studies, auto- biographies 
• Strengths of the idiographic approach- gives a detailed and global understanding of individual also leads to new ideas for more general research methodologies 
• Weaknesses of the idiographic approach- difficult to generalise the data, not sure whether data collected represents the larger group. May be unreliable. Also data is subjective to interpreter 
• Nomothetic approach: using group data in order to create theories and laws about people's behaviour in general
• Nomothetic laws fall into three categories: Classifying people into groups, creating principles of behaviour, producing behaviour scales or dimensions
• Strengths of the nomothetic approach: more scientific as can prove things about large groups of people also only approach that leads to laws (that can be empirically tested) 
• Weakness of the nomothetic approach: group study generalises and may not apply to the individual. Lacking ecological validity. 
• Ways data is collected for the nomothetic approach is through: analysis of groups- attempting to create laws and show that psych is an objective science. 

  Collects quantitative scientific data on basis only numbers permit statistical calculations (allowing prediction)- purpose of having laws