Texas Instruments TI Programmable 57 User Manual

LINEAR REGRESSION
SN
eee
The
formula
for
the
intercept
is:
b = y — mx
n
.
=
means
the
sum
of
all
data
coordinates
multiplied
together,
starting
at
1
and
going
to
n;(x,y;,
X2Y2,..-).
With
the
help
of
some
special
keys
on
your
calculator
and
the
program
we'll
develop,
you'll
be
able
to
solve
for
m
and
b
with
a
fraction
of
the
effort
normally
involved
in
handling
these
complex
formulas.
The
program
will
also
allow
you
to
use
your
data
to
make
predictions.
Once
you
find
m
and
b,
you'll
be
able
to
enter
a
new
“x”
value
and
get
its
corresponding
“predicted”
“y’
value
on
the
line
using
the
formula
y
=
mx
+
b,
Oryoucan
entera
"y”
value
and
“predict”
the
yee
corresponding
x"
value
on
the
line
using
the
equation
i
b
This
program
also
lets
you
find
a
number
called
the
deettictent
of
determination
(labeled
r).
The
number
r
(computed
from
r’
with
a
simple
keystroke)
is
called
the
absolute
value
of
the
correlation
coefficient.
This
is
a
measure
of
how
well
your
data
points
correspond
or
correlate
to
your
line.
This
helps
determine
the
accuracy
of
predictions
you
make
from
your
line.
A
value
close
to
|
indicates
a
high
correlation.
(The
calculator
could
fit
your
points
accurately
to
a
trend
line.)
A
value
close
to
zero
indicates
that
the
sets
of
data
have
a
low
correlation
and
the
trend
line
developed
by
the
calculator
is
not
as
reliable
for
predictions.
The
formula
for
r’ is:
m? Ox?
ois
The
program
we're
about
to
embark
on
involves
many,
many
calculations
and
will
pretty
well
“load
up”
your
calculator.
The
important
point
is
that
with
your
calculator
handling
the
difficult
mathematics,
you
can
use
the
powerful
tools
of
linear
regression
for
prediction
and
planning,
without
getting
stopped
by
the
mass
of
computation
involved.
r=

Texas Instruments TI Programmable 57 Specifications

General

Brand	Texas Instruments
Model	TI Programmable 57
Category	Calculator
Language	English