Lesson 9 - Measurement In Evaluation Flashcards
(35 cards)
What is the core essence of validity?
Accuracy
Is the scale accurate each time you step on it?
What are the 4 major types of validity?
- Face Validity
- Content Validity
- Criterion Validity
- Construct Validity
Define Face Validity
Extent to which the instrument APPEARS to be measuring what it is supposed to measure.
- Face validity assesses whether the test “looks valid” to the examinees who take it, the administrative personnel who decide on its use, and other technically untrained observers.
What is one way it can be determined if the instrument has face validity?
Ask a colleague to look over an instrument and see if s/he agrees that it appears to measure what you intend to measure.
What is a problem with a colleague determining face validity?
It is a SUBJECTIVE opinion
- Depends on who you ask and what they know.
How does Face Validity differ from the other forms of validity?
Face validity lacks some form of systematic logical analysis of the content.
Define Content Validity
The degree to which the items within a research instrument represent the universe of content for the concept being measured or the domain of a given behavior.
- A type of face validity
- Subjective
- Cost effective
In what type of validity do you ask multiple ‘experts’ in the field to evaluate the instrument?
Content Validity
- Problem with this is that it is subjective
Who should Content Validity be conducted by?
- persons with technical expertise to make sound judgements
- persons with a willingness to provide, if necessary, negative feedback
- professionals with diverse experience
Since neither content or face validity are sufficient for establishing that a scale has ‘true’ validity, why use them?
- no other way
- most cost effective
Define Criterion Validity
Criterion validity is the extent to which the measures are demonstrably related to concrete criteria in the “real” world.
What are the two subtypes of criterion validity?
Predictive and concurrent validity
Define Concurrent Validity
Concurrent validity is demonstrated where a test correlates well with a measure that has previously been validated. The two measures are taken at the same time.
(current status)
What is the main difference b/w concurrent and predictive validity?
The difference between concurrent validity and predictive validity rests solely on the time at which the two measures are administered.
Define Predictive Validity
Predictive validity is where one measure occurs earlier and is meant to predict some later measure.
(Future performance)
In cases when there is not an existing criterion from which to compare, or the phenomenon that planners want to measure is more abstract than concrete, how can validity be established?
Using construct validity
Define construct validity
Construct validity is the degree to which a measure correlates with other measures it is THEORETICALLY expected to correlate with.
What is the core essence of reliability?
Consistency
The scale be be consistently wrong or right
What are the two major approaches to reliability?
- Internal consistency reliability
2. Test-retest reliability
How is internal consistency reliability established?
Each item that makes up a scale is examined for how well it correlates with the scale as a whole.
- Consistency across all parts of an instrument
How can test-retest reliability be established?
By measuring the same group at two different points in time times (day, year, etc)
Although both must be considered, which is more important validity or reliability and why?
Validity because if an instrument doesn’t accurately measure what it is suppose to measure (validity), then reliability is an irrelevant issue. a
(Consistently supplying a wrong answer)
Often must reliability and validity be assessed?
EACH time the instrument is administered to a sample.
Why may you NOT cite past experiences or existing data on psychometric properties?
Cannot simply cite past experience or existing data on psychometric properties because each group will respond differently.