# HP 50g User Manual Page 621

Graphing calculator.

Procedure for inference statistics for linear regression using the
calculator
1) Enter (x,y) as columns of data in the statistical matrix DAT.
2) Produce a scatterplot for the appropriate columns of
appropriate H- and V-VIEWS to check linear trend.
3) Use ‚Ù˜˜@@@OK@@@, to fit straight line, and get a, b, s
(Covariance), and r
4) Use ‚Ù˜@@@OK@@@,
statistics for x while column 2 will show the statistics for y.
5) Calculate
6) For either confidence intervals or two-tailed tests, obtain t
)100% confidence, from t-distribution with
7) For one- or two-tailed tests, find the value of t using the appropriate
equation for either
8) For confidence intervals use the appropriate formulas as shown above.
Example 1 -- For the following (x,y) data, determine the 95% confidence
interval for the slope B and the intercept A
Enter the (x,y) data in columns 1 and 2 of DAT, respectively. A scatterplot of
the data shows a good linear trend:
Use the
Fit Data..
a+b x+(t
(Correlation).
xy
to obtain x, y, s
S
(
n
) 1
s
xx
or . Reject the null hypothesis if
x
2.0
2.5
y
5.5
option in the ‚Ù menu, to get:
3: '-.86 + 3.24*X'
2: Correlation: 0.989720229749
) s
n-2,
/2
n
1
2
s
2
e
n
2
x
,
3.0
3.5
7.2
9.4
10.0
[1+(1/n)+(x
e
0
, s
. Column 1 will show the
x
y
2
2
s
1 (
r
)
y
xy
= n -2.
P-value
4.0
12.2
2
1/2
- x)
/S
]
.
xx
DAT, and use
xy
, with (1-
/2
< .
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