1000 š4.1 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{} for the standard deviation of x–values. Press {2{} 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 (sx) 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:

zb{´}



Clears the statistics registers.

15.5

6

) Enters the first time.

9.25

610 612.5



Enters the remaining data; six

612 68.5 6 ) data points entered.

{2{ %}

)  Calculates the standard deviation

 

time.

11–6 Statistical Operations

File name 32sii-Manual-E-0424

 

Printed Date : 2003/4/24

Size : 17.7 x 25.2 cm