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right side without reading the description of the words. It is a
versatile scale but difficult to apply.

c. Staple scale
The staple scale was originally developed to measure the
◆ Direction and direction and intensity of an attitude simultaneously. Modern
intensity versions of this place a single adjective as a substitute for semantic
differential when it is difficult to create pairs of bipolar adjectives.
This scale measures how close to or how distant from the adjectives
a given stimulus is perceived to be. It is a unipolar ten-point scale
(For example, -5 to +5) without a neutral point (zero). It is easy to
construct but is confusing and difficult to apply.

3.2.3 Goodness of Measurement Scales

A measurement scale must have certain desirable characteristics
or criteria to judge its goodness, so that one must have faith
or confidence that the scale will measure what it is intended to
measure and will measure it consistently and accurately in an
inexpensive way.
They are

◆ Reliability

◆ Validity
◆ Practicality

These characteristics are described below:

a. Reliability
Reliability deals with the accuracy and precision of a
measurement procedure. The accuracy of a measurement scale
implies that it must give a real value. In popular language it means
◆ Accuracy and that if a person’s height is 180 cm, the measurement scale should
precision indicate 180cm on the scale. The precision, however, signifies the
power to discriminate or distinguish and indicates the degree of
precision that can be achieved with the scale of measurement. The
Fahrenheit scale for measuring temperature is more accurate than
the Celsius scale. Ratings out of, say, 100 provide greater precision
and accuracy than simply rating students A+, A, B+, B and C.

Reliability indicates the confidence one can be in the
measurement obtained from the scale. It is the consistency with
which a measurement instrument measures a given characteristic
or concept, that is, if the same object, characteristics or attitude are
measured over and over again, approximately the same conclusion
would be reached. However, it can be emphasised that reliability
does not necessarily imply that the measuring instrument is also

110 SGOU - SLM -MCom Research Methodology