The pitfalls of "mental tests" / by Charles S. Myers.

  • Charles Samuel Myers
Date:
[1911?]
Catalogue details

Licence: In copyright

Credit: The pitfalls of "mental tests" / by Charles S. Myers. Source: Wellcome Collection.

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    acting influences are thrown into the statistical melting pot, is it surprising that the result is a mere blur, showing an absence of significant correlation, a small correlation in one direction in one school and in an inverse direction in another ? This neglect to analyse and to take heed of what is actually being measured is specially prone to occur in the use of mental tests. In other sciences there is little or no real difficulty in observing what we are measuring, if only the experimenter take reasonable care. But in psychology we’ can only ascertain what we are testing by recourse to introspection on the part of the subject. To neglect introspection in psychological experiment is usually to court certain disaster. If we are in total ignorance of what has been going on in the mind of the subject during the experiment, it is rarely possible to argue from the objective data—from the measurements which it yields. For example, we may be trying to determine whether any correlation exists between sensory discrimination and general intelligence. A positive result may be simply due to the fact that the very nature of the test has compelled the subject to use his intelligence while carrying out sensory discriminations. We may be correlating mental ability with mental fatigue, and neglect the fact that sometimes we may not be measuring fatigue at all, that in some subjects the task becomes automatic, in others tedious, or that boredom may be in others over¬ come by motives of duty or ambition. We may be test¬ ing the visual acuity of two persons and obtain a different result from each, despite the fact that really they have the same visual acuity. The result may be due to the fact that the one subject strains every effort to interpret what he but dimly sees, while the other only reads what he believes he can clearly see. Thus again we merely obtain a blurred or erroneous result from the blind applications of statistical methods to measurements which are really meaningless owing to our failure to analyze the conditions determining the character we are measuring.
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