8-3
Statistics: Range and Standard Deviation
•
statisticians need to know what the
central tendency
of a
set of scores is: mean, median
•
they also want to know how “spread out” the scores are
•
statistics that measure the spread are called
measures of
dispersion
R
ANGE
The
range
of a set of scores is the distance from lowest to
highest score:
range
= (high score – low score)
S
TANDARD
D
EVIATION
•
the most commonly used measure of dispersion
•
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- Spring '11
- Staff
- Statistics, Standard Deviation
-
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