test and measurements week4

Validity: The Test Doth Purport Too Much, Methinks

In your unit readings, you read about two approaches or models of validity—trinitarian and unitary. In some ways, these two models are competing views of gathering evidence for a test's validity. In other ways, the two approaches have an overlap of elements.

In your post:

• Compare and contrast these two models in terms of how they conceptualize validity.
• Identify at least one advantage and disadvantage of each model.
• Decide which model appears to be the most valid for determining validity of a test.
• Explain your decision in terms of the implications for decision making about a test's validity.

Be sure to include citations from Guion's 1980 article, "On Trinitarian Doctrines of Validity," and Messick's 1995 article, "Validity of Psychological Assessment: Validation of Inferences From Persons' Responses and Performances As Scientific Inquiry Into Score Meaning."