Sample standard deviation – HP 32SII User Manual
Page 154
11–6 Statistical
Operations
File name 32sii-Manual-E-0424
Printed Date : 2003/4/24 Size : 17.7 x 25.2 cm
1000
4.1
6
)
Four data pairs accumulated.
{
/
{
·
º
}
)
Calculates the mean price
weighted for the quantity
purchased.
Sample Standard Deviation
Sample standard deviation is a measure of how dispersed the data values are
about the mean. standard deviation assumes the data is a sampling of a
larger, complete set of data, and is calculated using n – 1 as a divisor.
Press
{
2
{
Uº
} for the standard deviation of x–values.
Press
{
2
{
U¸
} for the standard deviation of y–values.
The {
σº
} and {
σ¸
} keys in this menu are described in the next section,
"Population Standard Deviation."
Example:
Sample Standard Deviation.
Using the same process–times as in the above "mean" example, May Kitt
now wants to determine the standard deviation time (s
x
) of the process:
15.5
9.25
10.0
12.5 12.0 8.5
Calculate the standard deviation of the times. (Treat all the data as x–values.)
Keys: Display: Description:
z
b
{
´
}
Clears the statistics registers.
15.5
6
)
Enters the first time.
9.25
6
10
6
12.5
6
12
6
8.5
6
)
Enters the remaining data; six
data points entered.
{
2
{
%
}
)
Calculates the standard deviation
time.