Statistical infrequency

Statistical infrequency 

• Any relatively usual behaviour/characteristic can be thought of as ‘normal’ and any behaviour that is different to this is ‘abnormal’.
• Abnormality is defined as those behaviours that are rare - any behaviour that is found in very few people is regarded as abnormal. 
• Example: average IQ - 100. Most people have IQ from 85-115. 2% have score below 70 - statistically ‘abnormal’ + diagnosed with intellectual disability disorder

Evaluation

• Real life application…