statistical infrequency

• P: the main issue is that there are many abnormal behaviours that are actually quite desirable

  E: very few people have an IQ over 150 but this abnormality is desirable not undesirable. equally, there are some 'normal' behaviours that are undesirable.

  L: therefore, using statistical infrequency to define abnormality means that we are unable to distinguish between desirable and undesirable behaviours
• P: the fact that cut-off points are subjectively determined is a limitation

  E: if abnormality is defined in terms of statistical infrequency, we need to decide where to separate normality from abnormality. on of the symptoms of depression is 'difficulty sleeping'. some people might think abnormal sleep is less than 6 hours a nigh, others might think the cut-off should be 5 hours

  L: such disagreements mean its difficult to define abnormality in terms of statistical infrequency
• P: in some situations it is appropriate to use a statistical criterion to define abnormality

  E: intellectual disability is defined in terms of normal distribution using the concept of standard deviation to establish a cut-off point for abnormality. any individual whose IQ is more than 2 standard deviations below the mean is judged as having a mental disorder

  L: this suggests that statistical infrequency is only one of a number of tools