lecture 31 worksheet
3
Problem
3
: Significant regression?
Combine your answer in Problem
2
(where you got the estimator for
the noise variance) with your calculation of
S
xx
=
Â
(
x
i

x
)
2
1
to
1
Remember that
x
is the fluoride level.
decide whether the regression is significant or not using
a
=
5%.
Answer to Problem
3
.
How about for
a
=
0.2%? We do not need to recalculate every
thing, right? By the way, this can prove interesting for identifying
P
values, even using the
T
distribution critical values!
x
=
E
=
2
=
1.32
Sox
=
[(x
x)
=
(0.98)

(1.285...
=
3.6h
H.:
B,
=
0,
M,:
B,
o
To
=
SY
4.25
0.025,0
2.306
Reject,
Repression
Strat