Standard Deviation - HP 0012C-90001 User Manual

Standard Deviation

Standard Deviation Standard Deviation Standard Deviation
Pressing gv calculates the standard deviation of the
y-value s
s ( ). (The standard deviation of a set of data is a measure of the dispersion
y
around the mean.) The standard deviation of the
after v is pressed; to display the standard deviation of the
Example: To calculate the standard deviations of the Example: Example: Example:
from the preceding example:
Keystrokes Keystrokes
Keystrokes Keystrokes
gv
~
The formulas used in the hp 12c for calculating
population standard deviation based on a sample of the population. Thus, current
statistical convention calls them
that the seven salespersons are a sample of the population of
our formulas derive best estimates of the population from the sample.
What if the seven salespersons constituted the whole population of salespersons.
Then we wouldn't need to
true population
find the
population, using the following keystrokes.
Keystrokes Keystrokes Keystrokes Keystrokes
gÖ
_
gv
~
To continue summing data pairs, press gÖg^ before entering more data.
*
It turns out that if you sum the mean of the population into the set itself and find the new
computed using the formulas on page 192, that
, of the original set.
Section 6: Statistics Functions Section 6:
Section 6: Section 6:
Display Display
Display Display
4,820.59
Standard deviation of sales.
6.03
Standard deviation of hours worked.
sample
standard deviations. So we have assumed
estimate population
the
standard deviation () when the data set equals the total
*
Display Display Display Display
21,714.29 Mean (dollars)
8.00 Number of entries + 1.

4,463.00

5.58
s will be the
Statistics Functions
Statistics Functions Statistics Functions
x-value s
s (
x-value
s appears in the display
y-value s, press ~.
x-value
s and of the
s s best estimates
, and give
x y
all salespersons
standard deviation. We can
x
y
population standard deviation,
79 79
79 79
) and of the
x
y-value
s
of the
, and
s
,