This preview shows pages 1–3. Sign up to view the full content.
1
Posted after class.
WEEK 14 – Mon, Nov 29
HYPOTHESIS TESTING – Critical Value Approach
(Background material is in Chapter 7)
Tests for Mean μ
Population Standard Deviation σ Known  a ztest.
The test statistic
is
where
or
The textbook ignores the size of the population and on p. 272 shows the test statistic as
without displaying the subscript on μ.
Steps for an αlevel, righttailed
ztest of H
0
: μ ≤ μ
0
v.
H
1
: μ > μ
0
.
a.
Determine the critical value for z, namely, c = z
α
.
b.
Gather the data, determine
.
Calculate z.
c.
Compare the observed z to the critical value.
If z > z
α
, Reject H
0
in favor of H
1
.
If z ≤ z
α
, Retain H
0
.
Steps for an αlevel, lefttailed
ztest of H
0
: μ ≥ μ
0
v.
H
1
: μ < μ
0
.
a.
Determine the critical value for z, namely, c = z
α
.
b.
Gather the data, determine
.
Calculate z.
c.
Compare the observed z to the critical value.
If z < z
α
, Reject H
0
in favor of H
1
.
If z ≥ z
α
, Retain H
0
.
Steps for an αlevel, twotailed
ztest of H
0
: μ = μ
0
v.
H
1
: μ ≠ μ
0
.
a.
Determine the critical values for z, namely, c
1
= z
α/2
and c
2
= z
α/2
.
b.
Gather the data, determine
.
Calculate z.
c.
Compare the observed z to the critical values.
If either z < z
α/2
or z > z
α/2
, Reject
H
0
in favor of H
1
.
If z
α/2
≤ z ≤ z
α/2
, Retain H
0
.
This preview has intentionally blurred sections. Sign up to view the full version.
View Full Document2
Population Standard Deviation σ Unknown  a ttest.
The test
statistic is
where
or
The textbook ignores the size of the population and on p. 272 shows the test statistic as
without displaying the subscript on μ.
Steps for an αlevel, righttailed
ttest of H
0
: μ ≤ μ
0
v.
H
1
: μ > μ
0
.
a.
Determine the critical value for t, namely, c = t
α
based on n – 1
df
.
b.
Gather the data, determine
and s.
Calculate t.
c.
Compare the observed t to the critical value.
If t > t
α
, Reject H
0
in favor of H
1
.
If
t ≤ t
α
, Retain H
0
.
Steps for an αlevel, lefttailed
ttest of H
0
: μ ≥ μ
0
v.
H
1
: μ < μ
0
.
a.
Determine the critical value for t, namely, c = t
α
based on n – 1
df
.
b.
Gather the data, determine
and s.
Calculate t.
c.
Compare the observed t to the critical value.
If t < t
α
, Reject H
0
in favor of H
1
.
If t ≥ t
α
, Retain H
0
.
Steps for an αlevel, twotailed
ttest of H
0
: μ = μ
0
v.
H
1
: μ ≠ μ
0
.
a.
Determine the critical values for t, namely, c
1
= t
α/2
and c
2
= t
α/2
, based on n – 1
df
.
b.
Gather the data, determine
and s.
Calculate t.
c.
Compare the observed t to the critical values.
If either t < t
α/2
or t > t
α/2
, Reject
H
0
in favor of H
1
.
If t
α/2
≤ t ≤ t
α/2
, Retain H
0
.
Note
This is the end of the preview. Sign up
to
access the rest of the document.
 Summer '10
 DennisGilliland
 Standard Deviation

Click to edit the document details