Describes the characteristics of good test.

1. 23-11-2015
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Validity, Reliability, Objectivity,
Usability, difficulty index and
discrimination power
Dr. V. Singh
SXCE, Patna
Validity
• Validity of a test is concerned with the specific
purpose for which it is developed. It refers to
the extent to which the results of an
evaluation procedure serve the particular uses
for which they are intended.
Compiled by:Dr.V.Singh

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Content(face) Validity
• Content validity of a test indicates that the
test has proper representation of learning
tasks to be performed by the learners. It is
obtained by subjecting the test to the
judgment of several subject experts and test
specialists.
Compiled by:Dr.V.Singh
Criterion-related validity
• Criterion related validity of a test is concerned
with predicting future performance(predictive
validity) of the test takers or evaluating their
current performance in a test against some
‘criterion’ (concurrent validity). Ex. GATE score
sre used to predict the future performance of
the students.
• The other case it is correlated with some pre-
prepared test to check the concurrent validity.
Compiled by:Dr.V.Singh

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Construct Validity
• When we intend to measure certain
psychological constructs , we think of
establishing constructs validity. A construct is
a trait or ability, temperament, or attitude
which is hypothesized to explain certain
aspects of behavior such as ‘achievement
motivation’ . ‘ intelligence’ or test of anxiety’
Compiled by:Dr.V.Singh
Validity Coefficient
• The validity of a test is always reported in
terms of validity coefficient. A validity
coefficient of at least +0.70 or more can be
treated as a s a good test.
Compiled by:Dr.V.Singh

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Reliability
• The second important characteristics of a test
is its reliability. Reliability is commonly known
as consistency . In a testing situation,
reliability refers to consistency of test results
when the test is administered to the same
individuals with the same conditions. Cohen
et. al (2000).
Compiled by:Dr.V.Singh
• Test- retest method
• Equivalent or parallel forms method
• Split-half method
• Rational-equivalence method
The reliability of a test is reported in terms of
reliability coefficient.
Compiled by:Dr.V.Singh

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• Usability(easy to administer, scoring,
interpretation and application, availability
etc.)
• Objectivity
Compiled by:Dr.V.Singh
Item analysis
• The difficulty level of the item
• The discrimination power of the item
• The effectiveness of alternative
Compiled by:Dr.V.Singh