statistical infrequency

• what is the idea with this definition?

  Behaviours that are statistically rare should be seen as abnormal
• what is gathered?

  statistics are gathered that claim to measure certain characteristics and behaviours, with a view to showing how they are distributed throughout the general population
• what does what is regarded as statistically rare depend on?

  normal distribution
• what is the purpose of drawing a normal distribution curve?

  to show what proportions of people share the characteristics or behaviour in question

  • most people will be on or near the mean for these characteristics or behaviours with declining amounts of people away from the mean (either above or below it)
• who is perceived as abnormal?

  any individuals who fall outside the 'normal distribution' , usually abouit 5% of a population (two standard deviation points away from the mean)
• the definition goes no further than .........?

  declaring which behaviours are abnornmal and the definition makes no judgements about quality of life or the nature of mental disorders
• give 3 strengths of the definition?

  • CAN BE APPROPRIATE: in many situations statistical criteria can define abnormality (eg mental retardation)
  • BASED ON REAL DATA- the definition relies on real, unbiased data and so is an OBJECTIVE means of defining abnormality
  • OVERALL VIEW- gives an overview of what behaviours and characteristics are infrequent within a given population
• give 3 limitations of the definition?

  • CULTURAL FACTORS- doesn't consider cultural factors- what is statistically normal in one culture may not be in another, this can lead to the issue of judging people in one culture by the statistical norms of another culture
• give 2 more limitations of the definition?


  • WHERE TO DRAW THE LINE- its not clear how far behaviour should deviate from the norm to be seen as abnormal. many disorders eg depression, vary greatly between people in terms of severity
  • NOT ALL INFREQUENT BEHAVIOURS (THOSE SHOWING STATISTICAL INFREQUENCY) ARE ABNORMAL- some rare behaviours and characteristics are desirable rather than undesirable eg high intelligence is statistically rare but DESIRABLE