Lecture 4 - Test Construction Flashcards
What are the four types of scaling methods?
- nominal
- ordinal
- interval
- ratio
What is nominal?
used to name/classify a characteristic, number is a description of the individuals category they belong to
What is ordinal?
the numbers indicate the order/rank of the individual.
What is interval?
classic interval scale is temperature - no true 0
What is ratio?
equal intervals between scores - 0 means an absence of a characteristic
What is matching?
essentially a multiple choice item - used when a number of items can use the same set of answers
What are the two item formats?
- selection type - select an item that gives an answer to the question
- supply type
What are the types of supply types?
essay - extended response
essay - restricted response
short answer
What are the three factors for item analysis?
- the difficulty of an item
- the discrimination power of an item
- the effectiveness of each alternative
What is the range for the difficulty of an item?
0 to 1
What does 0 and 1 mean for the difficulty of an item?
0- no one selected the correct answer and the item is too hard
1- everyone selected it and the item is too easy
What do we aim for in a difficulty level?
.5
What is the range for the discrimination power of an item?
-1 to +1
What does 0 mean in the discrimination power of an item?
proportions are equal in the two halves - item that does not discriminate well
What does +1 mean in the discrimination power of an item?
ideal, means all the people in the upper half get it right and all the people in the lower half get it wrong
