HP (Hewlett-Packard) 50g ユーザーズマニュアル

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The range of the sample is the difference between the maximum and minimum 
values of the sample.  Since the calculator, through the pre-programmed 
statistical functions provides the maximum and minimum values of the sample, 
you can easily calculate the range.
Coefficient of variation
The coefficient of  variation of a sample combines the mean, a measure of 
central tendency, with the standard deviation, a measure of spreading, and is 
defined, as a percentage, by: V
x
 = (s
x
/
⎯x)100.
Sample vs. population
The pre-programmed functions for single-variable statistics used above can be 
applied to a finite population by selecting the 
Type: Population
 in the 
SINGLE-VARIABLE STATISTICS
 screen.  The main difference is in the values of 
the variance and standard deviation which are calculated using n in the 
denominator of the variance, rather than (n-1).  
Example 3 --  If you were to repeat the exercise in Example 1 of this section, 
using 
Population
 rather than 
Sample
 as the 
Type
, you will get the same 
values for the mean, total, maximum, and minimum.  The variance and 
standard deviation, however, will be given by:  Variance: 0.852, Std Dev: 
0.923.
Obtaining frequency distributions
The application 
2. Frequencies..
 in the STAT menu can be used to obtain 
frequency distributions for a set of data.  Again, the data must be present in the 
form of a column vector stored in variable 
ΣDAT.  To get started, press 
‚Ù˜ @@@OK@@@.  The resulting input form contains the following fields:
ΣDAT
the matrix containing the data of interest.
Col
: the 
column 
of 
ΣDAT that is under scrutiny.
X-Min
the minimum class boundary (default = -6.5).
Bin Count
the number of classes(default = 13).
Bin Width
:
the uniform width of each class (default = 1).