Answer:
RELIBILITY - is the consistency of your measurement, or the degree to which an
instrument measures the same way each time it is used under the same condition with the
same subjects. In short, it is the repeatability of your measurement. A measure is considered
reliable if a person's score on the same test given twice is similar. It is important to
remember that reliability is not measured, it is estimated. A good instrument will produce
consistent scores. An instrument’s reliability is estimated using a correlation coefficient of
one type or another.
VALIDITY
VALIDITY - Validity is the extent to which a test measures what it claims to measure. It is
vital for a test to be valid in order for the results to be accurately applied and interpreted.
Validity isn’t determined by a single statistic, but by a body of research that demonstrates
the relationship between the test and the behavior it is intended to measure. There are three
types of validity: It is the strength of our conclusions, inferences or propositions. More
formally, Cook and Campbell (1979) define it as the "best available approximation to the
truth or falsity of a given inference, proposition or conclusion."
PRACTICIBILITY
PRACTICIBILITY - It should be feasible & usable. Quality of being usable in context to the
objective to be achieved.
USABILITY
USABILITY(practicality) ease in administration, scoring, interpretation and application, low
cost, proper mechanical make – up
MEASUREABILITY
MEASUREABILITY - It should measure the objective to be achieved.
Explanation:
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