Longman Dictionary of

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standard dialect
where X a raw score
X – the mean
N the number of participants in a study (or items on a test)
the sum of
standard dialect n
another term for STANDARD VARIETY
Standard English n
see STANDARD VARIETY
standard error n
also SE
(in statistics and testing) a statistic used for determining the degree to which
the estimate of a POPULATION PARAMETER is likely to differ from the computed
sample statistic. The standard error of a statistic provides an indication of
how accurate an estimate it is of the population parameter. One commonly
used standard error is the standard error of the mean, which indicates how
close the mean of the observed sample is to the mean of the entire population.
standard error of measurement n
also SEM
an estimate of the range of scores wherein a test taker’s TRUE SCORE lies.
The standard error of measurement decreases as the reliability of a test
increases which is shown by the following formula:
SEM SD√1 r
where SD the standard deviation of test scores
r the reliability estimate of a test
For example, a test taker obtained a score of 85 on an ESL reading test
that has a standard deviation of 12 and a reliability coefficient of .91. The
test’s SEM is estimated as follows:
SEM 12√1 0.91 12√0.09 (12)(0.3) 3.6
As a test taker’s true scores are expected to distribute normally if this
person took the same test an infinite number of times, this person’s true
score would be expected to lie within or one SEM of this person’s
observed score 68% of the time (i.e. between 88.6 and 81.4) and within
or two SEM of this person’s observed score 95% of the time (i.e.
between 92.2 and 77.8) (see THE NORMAL CURVE).
standard error of the mean n
see STANDARD ERROR
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