Definitions of Abnormality - Statistical Infrequency

Question 1

What makes a behaviour abnormal?

Answer 1

Behaviours that occur rarely.

Question 2

When is this useful?

Answer 2

When behaviours can be measured reliably and therefore plotted on a normal distribution curve.

Question 3

For measurable human characteristics where do most people’s scores cluster?

Answer 3

Around the mean.

Question 4

What happens as we move further away from the mean?

Answer 4

Fewer people will have that characteristic or score.

Question 5

Weakness 1

Answer 5

Issue with regarding infrequent behaviours as abnormal - e.g. we would not regard a genius IQ as abnormal.

Question 6

Weakness 2

Answer 6

Some frequently occurring behaviours are considered undesirable and abnormal e.g. depression is known as the common cold of psychiatry.

Question 7

Strength 1

Answer 7

It is an objective way of deciding upon abnormality - no value judgements are made. E.g. homosexuality used to be defined as a mental disorder. By this definition of abnormality it would not be seen as ‘unacceptable’ but just less frequent than heterosexuality.

Question 8

Strength 2

Answer 8

Some validity when it is appropriate to use a statistical criterion. E.g. intellectual disability defined in terms of normal distribution using standard deviation to establish cut off point for abnormality. IQ more than 2 SD’s below mean is judged as mental disorder. (Diagnosis only mad in conjunction with failure to function adequately).

Question 9

Weakness 3

Answer 9

The cut-off point is subjectively determined. Where do you separate normality from abnormality.

Question 10

Weakness 4

Answer 10

The concept of statistical infrequency allows us to identify abnormal behaviours but not which behaviours require treatment.