Final answer:
The multitrait-multimethod matrix is designed to establish discriminant validity, evaluating if a construct is distinct from others empirically.
Step-by-step explanation:
The multitrait-multimethod matrix is conducted in order to establish discriminant validity. Discriminant validity is the extent to which a construct is truly distinct from other constructs by empirical standards.
It helps in validating that the construct being measured is not a reflection of other variables but rather a distinct concept in itself.
Content validity involves whether a measure covers a representative sample of the domain of the concept in question. Face validity refers to how a test appears to measure what it is supposed to measure, simply from looking at its content, irrespective of whether it actually does. Predictive validity, on the other hand, assesses how well a test predicts future or intended behaviors.
Regarding the scientific method, validity of a theory is usually determined through empirical testing and confirmation, whereas the subjective elements like face validity can be more based on judgments rather than objective measures.