Longman Dictionary of

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scale n
(in statistics and testing) the level or type of quantification produced by a
measurement. Four different scales are often used:
a a nominal (or categorical) scale is used to assign values to items or individuals
that belong to different groups or categories. For example, we
may assign the number “1” to all male students and “2” to all female
students in a school. But these numbers are arbitrary and interchangeable.
Thus, instead of assigning “1” to male students and “2” to female
students, we can assign “1” to female students and “2” to male students.
ban ordinal scale makes use of ORDINAL NUMBERs (e.g. first, second,
third). It ranks items or individuals in order on the basis of some criterion.
For example, based on scores on a test, test takers may be rankordered
as first, second or third in comparison to others who took the
same test. However, the difference between the values on the scale is
not necessarily the same. Thus, the difference in points between being
first or second on a test may not be the same as the difference being
21st or 22nd.
c an interval scale is similar to an ordinal scale except that it has the
additional quality that the intervals between the points on the scale are
equal. For example, the difference between a temperature of 8°C and
6°C is the same as the difference between a temperature of 4°C and
2°C. However, we cannot say that a temperature of 8°C is twice as hot
as a temperature of 4°C because an interval scale does not have an
absolute zero.
d a ratio scale is similar to an interval scale except that it has an absolute
zero, which enables us to compare two points on the ratio scale and
make a statement such as “This point is three times as high as that
point”. A scale for measuring height is an example of a ratio scale.
Thus, we can say that a person whose height is 220 cm is twice as tall
as a person whose height is 110 cm.
Scales can be converted into other scales. However, the direction of scale
conversion is only one-way (i.e. a ratio scale → an interval scale → an
ordinal scale → a nominal scale), not the other way round.
scalogram n
see IMPLICATIONAL SCALING
scanning
scanning n
(in READING) a type of READING STRATEGY which is used when the reader
wants to locate a particular piece of information without necessarily
understanding the rest of a text or passage. For example, the reader may
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