TM 5-6675-323-14
Display
Keystrokes
First score is entered.
1.0000
Since this problem involves
only one variable, y-value
d o e s not have to be entered
into Y-register using the
key.
D i s p l a y shows number of scores
2.0000
entered so far.
3.0000
4.0000
5.0000
6.0000
7.0000
Last score in sample.
8.0000
Standard deviation of test
7.8365
scores.
( 5 ) L i n e a r r e g r e s s on. L i n e a r r e g r e s s i o n i s a s t a t i s t i c a l m e t h o d f o r f i n d i n g
a straight line that best fits a set of data points, thus providing a relationship
between two variables.
(a) To use the linear regression function. first key in a series of data
points
using
the
key.
Then
press
L.R.
(b)
When
L.R.
if
pressed:
The contents of the stack registers are lifted just as they are when you
press
.
The slope (A) of the least squares line of the data is available in the
Y-register
of the stack.
The y-intercept (B) of the least squares line of the data appears in the
displayed X-register of the stack.
(c) To use value for A or to bring it into displayed X-register, simply
shift
stack
contents
with
the
key.
Example:
An oil company wishes to know the slope and y-intercept of a least
squares line for the consumption of motor fuel in the United States against time
It knows the data given in the table.
since 1945.
13-32
