TM 5-6675-313-14
Keystrokes
Di spl ay
1.0000
2.0000
First score is entered.
Since this problem involves
only one variable, y-value
does not have to be entered
into Y-register using the
_ key.
Display shows number of scores
entered so far.
3.0000
4.0000
5.0000
6.0000
7.0000
8.0000
Last score in sample.
7.8365
Standard deviation of test
scores.
(5) Linear regression.
Linear regression is a statistical method for finding
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 n key. Then press
q
L.R.
(b) When
q
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
m 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
since 1945.
It knows the data given in the table.
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