Statistics Calculations With Sum Lists - HP -18C Owner's Manual

Statistics Calculations With SUM Lists
Press
BIll
to display the CALC menu, which is described in table 6-
2.
To display a particular statistical value, press the appropriate menu
key.
Table 6·2. The CALC Menu for SUM Lists
Menu Key Description
ImIi1I
Displays the sum of all the numbers in the list.
IiII1II
Displays the mean (arithmetic average) of the set of numbers.
IID'!mII
Displays the median. If you were to sort the numbers from
smallest to the largest, the median number would be half-way
down the list. If there is an even number of items, the median
is the mean of the middle two numbers.
I'iiiJ:iI
Displays the standard deviation: The standard deviation is a
measure of how dispersed the numbers are about the mean.
The larger the standard deviation, the larger the spread. A
standard deviation of 0 means that all the numbers are
identical.
II3'i1B
Displays the difference between the largest and smallest
number.
Displays the smallest (minimum) number in the list.
Displays the largest (maximum) number in the list.
Sorts the list so that numbers are ordered from smallest to
largest.
Displays the FRCST (forecast) menu, which is used to do
curve fitting and forecasting using the linear, exponential,
logarithmic, or power models .
• The formula used by the HP-18C calculates the sample standard deviation. The formula
assumes that the list of numbers is a sampling of a larger, complete set of data. If the list is,
in fact, the entire set of data, the true population standard deviation can be computed by
calculating the mean of the original list, placing that value into the list, and then calculating
the standard deviation.
100 6: Running Total and Statistics Calculations