A good test should possess the following qualities.
• Objectivity
• Objective Basedness
• Comprehensiveness
• Validity
• Reliability
• Practicability
• Comparability
• Utility
Objectivity
• A test is said to be objective if it is free from personal biases in interpreting its scope as well as in scoring the responses.
• Objectivity of a test can be increased by using more objective type test items and the answers are scored according to model answers provided.
Objective Basedness
• The test should be based on pre-determined objectives.
• The test setter should have definite idea about the objective behind each item.
Comprehensiveness
• The test should cover the whole syllabus.
• Due importance should be given all the relevant learning materials.
• Test should be cover all the anticipated objectives.
Validity
• A said to be valid if it measures what it intends to measure.
• There are different types of validity:
– Operational validity
– Predictive validity
– Content validity
– Construct validity
• Operational Validity
– A test will have operational validity if the tasks required by the test are sufficient to evaluate the definite activities or qualities.
• Predictive Validity
– A test has predictive validity if scores on it predict future performance
• Content Validity
– If the items in the test constitute a representative sample of the total course content to be tested, the test can be said to have content validity.
• Construct Validity
– Construct validity involves explaining the test scores psychologically. A test is interpreted in terms of numerous research findings.
Reliability
• Reliability of a test refers to the degree of consistency with which it measures what it indented to measure.
• A test may be reliable but need not be valid. This is because it may yield consistent scores, but these scores need not be representing what exactly we want to measure.
• A test with high validity has to be reliable also. (the scores will be consistent in both cases)
• Valid test is also a reliable test, but a reliable test may not be a valid one
Different method for determining Reliability
• Test-retest method
– A test is administrated to the same group with short interval. The scores are tabulated and correlation is calculated. The higher the correlation, the more the reliability.
• Split-half method
– The scores of the odd and even items are taken and the correlation between the two sets of scores determined.
• Parallel form method
– Reliability is determined using two equivalent forms of the same test content.
– These prepared tests are administrated to the same group one after the other.
– The test forms should be identical with respect to the number of items, content, difficult level etc.
– Determining the correlation between the two sets of scores obtained by the group in the two tests.
– If higher the correlation, the more the reliability.
Discriminating Power
• Discriminating power of the test is its power to discriminate between the upper and lower groups who took the test.
• The test should contain different difficulty level of questions.
Practicability
• Practicability of the test depends up on...
• Administrative ease
• Scoring ease
• Interpretative ease
• Economy
Comparability
• A test possesses comparability when scores resulting from its use can be interpreted in terms of a common base that has a natural or accepted meanings
• There are two method for establishing comparability
– Availability of equivalent (parallel) form of test
– Availability of adequate norms
Utility
• A test has utility if it provides the test condition that would facilitate realization of the purpose for which it is mean.
