Psychological Measurement Exam 4 Flashcards
a statistic indicating how many test takers responded correctly to an item.
item-difficulty index
If 80% got item correct then item-difficulty index is ____.
.8
The larger item-difficulty index, the _____the item.
easier
You want an item difficulty to be halfway between that and 1, ex. for a 5 option multiple choice item, the probability of guessing correctly is .20, so the optimal item difficulty is therefore ____.
.60
.20+1.00=1.20
1.20/2=.60
provides an indication of the internal consistency of a test
item-reliability index
the higher the _____, the greater the tests internal consistency.
item-reliability index
What are the 3 test construction approaches?
- Rational approach
- Empirical approach
- Rational with empirical refinement approach
Making up statements about traits of a personality to tap every aspect
Ex. I am depressed once a month I am depressed a couple times a month I am depressed once a week I am depressed a couple times a week I am depressed everyday
This is easy to construct, easy to fake.
Rational approach to test construction
Uses 2 criterion groups, 1 normal and 1 exhibits trait that you want to tap into. Come up with an item pool of questions, give to both groups. Determine which questions are answered statistically significantly different.
Hard to fake because the questions are random and they don’t know what they’re being tested for.
Limitation - p
Empirical approach within test construction
Use rationality to come up with questions then run tests with 2 criterion groups and distinguish.
Rational with empirical refinement approach within test construction
What are the 5 steps in test development?
- Test conceptualization
- Test construction
- Test tryout
- Item analysis
- Test revision
Coming up with an idea that a test ought to be designed to measure [fill in the blank ] in [such and such ] way.
Test conceptualization
Preliminary research surrounding the creation of a prototype of the test.
Pilot work
Process of setting rules for assigning numbers in measurement.
Scaling
Grouping of words, statements, or symbols on which judgements of the strength of a particular trait, attitude, or emotion are indicated by the test taker.
Rating scale
Summative rating scale.
Presents test taker with five alternative responses.
Ex. Never, rarely, sometimes, usually, always
(each assigned a value [agreement])
Likert scale
Test takers are presented with pairs of stimuli (2 photos, 2 objects, 2 statements) which they are asked to compare. Must select one stimuli according to some rule (that they agree more with, etc.)
Method of paired comparisons
Printed cards, drawings, photos, objects, etc. are presented for evaluation.
Sorting tasks
Compare stimulus with others (ex. Rank)
Comparative scaling
Stimuli are placed in 1 of 2 or more categories.
Categorical scaling
Yields ordinal level measures.
Ex.
1. All people should have the right to decide whether they wish to end their lives.
2. People who are terminally ill and in pain should have the option to have a doctor assist them in ending their lives.
3. People should have the option to sign away the use of artificial life support equipment before they become seriously ill.
4. People have the right to a comfortable life.
All who agree with 1, also agree with 2, 3, 4…etc.
Guttman scale
Reservoir or well from which items will or will not be drawn from for the final version of the test.
Item pool
Form, plan, structure, arrangement, and layout of individual test items.
Item format
Requires test takers to select a response from a set of alternative responses.
Selected-response format