Clearing Statistical Data; Summary Of Statistical Calculations - HP -20S Owner's Manual

Clearing Statistical Data
Clear the statistical registers before entering new data so
that R4 through Ry are zero when you begin. If you don't
clear the registers, data currently stored in R, through Rg
is automatically included in the summation calculations.
To clear the statistical registers, press (] [CLZ]. The dis-
play and any pending operations are also cleared.
Summary of Statistical Calculations
Some functions return two values. The : annunciator indicates that
two values have been returned. Press (€] to see the hidden
value.
Keys
Description
(=)
to
Display
4 (n) Number of data points
5 (2x)
6 (Zy)
7 (2x?)
8 (Zy?)
9 (2xy)
entered.
Sum of the x-values.
Sum of the y-values.
Sum of the squares of
the x-values.
Sum of the squares of
the y-values.
Sum of the products of
the x- and y-values.
() 53]
() Gw]
Arithmetic mean (aver-
age) of the x-values.
Mean of the x-values
weighted by the y-
values.
Mean (average) of the
y-values if you entered
y-data.
5: Statistical Calculations 53