Posted after class
WEEK 12 – Mon, Nov 15
HYPOTHESIS TESTING – The pvalue Approach
(Background material is in Chapter 7)
Tests for Mean µ; the pvalue Approach
Population Standard Deviation σ Known  a ztest.
The test statistic is
which when standardized relative to the null distribution 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, righttail
ztest of H
0
: µ ≤ µ
0
v.
H
1
: µ > µ
0
.
a.
Gather the data, determine
.
Calculate z
obs
.
b.
Compute P(Z ≥ z
obs
).
If less than α, Reject H
0
in favor of H
1
.
Otherwise, Retain
H
1
.
Steps for an αlevel, lefttail
ztest of H
0
: µ ≥ µ
0
v.
H
1
: µ < µ
0
.
a.
Gather the data, determine
.
Calculate z
obs
.
b.
Compute P(Z ≤ z
obs
).
If less than α, Reject H
0
in favor of H
1
.
Otherwise, Retain
H
1
.
Steps for an αlevel, twotail
ztest of H
0
: µ = µ
0
v.
H
1
: µ ≠ µ
0
.
a.
Gather the data, determine
.
Calculate z
obs
.
b.
Compute the tail probability associated with z
obs
and
double it
.
If less than α,
Reject H
0
in favor of H
1
.
Otherwise, Retain H
1
.
1
This preview has intentionally blurred sections. Sign up to view the full version.
View Full DocumentPopulation Standard Deviation σ Unknown  a ttest.
The test statistic is
where
or
with
n
– 1 df.
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, righttail
ttest of H
0
: µ ≤ µ
0
v.
H
1
: µ > µ
0
.
a.
Gather the data, determine
.
Calculate t
obs
.
b.
Compute P(t ≥ t
obs
).
If less than α, Reject H
0
in favor of H
1
.
Otherwise, Retain
H
1
.
Steps for an αlevel, lefttail
ttest of H
0
: µ ≥ µ
0
v.
H
1
: µ < µ
0
.
a.
Gather the data, determine
.
Calculate t
obs
.
b.
Compute P(t ≤ t
obs
).
If less than α, Reject H
0
in favor of H
1
.
Otherwise, Retain
H
1
.
Steps for an αlevel, twotail
ttest of H
0
: µ = µ
0
v.
H
1
: µ ≠ µ
0
.
a.
Gather the data, determine
.
Calculate t
obs
.
b.
Compute the tail probability associated with t
obs
and
double it
.
If less than α,
Reject H
0
in favor of H
1
.
Otherwise, Retain H
1
.
Calculating the pvalue of t
This is the end of the preview. Sign up
to
access the rest of the document.
 Spring '08
 Anderson
 Statistics, Normal Distribution, Statistical hypothesis testing, H0, tobs, a. Gather

Click to edit the document details