STAT
35000
Name
erint:
D
In-Class-Activity
21
Time
Limit:
10
Minutes
Instructor:
'
This
working
sheet
contains
1
page
and
1
problem.
Check
to
see
if
any
pages
are
missing.
Enter
all
requested
information
on
the
top
of
this
page.
1.
Avote
is
to
be
taken
among
the
residents
of
a
city
and
its
northern
suburb
to
determine
whether
a
proposed
recreation
center
should
be
constructed
just
northwest
of
the
city
(and
west
of
the
suburb).
To
determine
if
a
higher
proportion
of
suburb
residents
favor
construction
than
city
residents,
a
poll
is
taken.
(a)
(5
points)
If
300
of
500
city
residents
favor
the
proposal
and
280
of
400
suburb
residents
favor
it,
would
you
agree
that
the
proportion
of
suburb
residents
favoring
the
proposal
is
higher
than
the
proportion
of
city
residents?
Use
an
a
=
0.05.
HO:
P,:Pz
VSs.
H1:
,
<
F,
Group1:
(',r;j
Res
and
Group
2:
Subprb
(222,
Data:
h'
:500/
)(,
~
200
é
Assume:alpha=
(05
P'
s
(Y
Statistic:
7,
=Hoo,
x,
=226
P
-
L&
-
'7
fl,
j-
-
772_
N
'
(6
-"76)
57
oren(
0
'07
=
:{i——""""--
—————T"
~
=31
|544p]
c=a
(
4'L/
]
*60O
X
YO
'
70441
1
36
=
)
6HY
ST
\
906
—mo
i
P-v
=
f
-
.
D'
[HYC
-
.
alue
]
2.4=
-3
\l/_
m/J
=
pnorm(_
2
(gqqo/)
=
0°666306
4207
Decision:
Fail
to
Reject
/
Reject
HOat
4
_
4,
65
Conclusion:
[)tz
90(00'"'*
eloipn
Ao
I'M'Z/flc
r
pro
//'ar"',"l'cr
6f
subunk
ol
cd
tovse
Hu
pospesal
Hron
@{4—9
P
esiclents
(b}
(3
points)
Redo
the
problem
with
a
smaller
sample:
If
75
of
125
city
residents
favor
the
proposal
and
70
of
100
suburb
residents
favor
the
proposal.
Use
an
a
=
0.05,
|
|
|
l
)
=n'06737
=
|
67724
|
P.
valus
:pmrm(—
|
E77D
L
0'07
7!
\
'
c—o?'"'-'*!;m
-
)
#'-_-1_2"
.
;6
'V&
o=
1065
!
&
S
<
¥
Y
)
P-VY?
;
:
|
\
'
.
HL'/'L/
_&'u'_'_p
wj(,L
"o
0,'
X-
'0F
|
(c)
(1
points)
Why
the
decisions
in
(a)
and
(b)
differ.
M
dfl.&(.".bflf
;'n
J»—l"l,
Pfi(\fl.oufi
2
fo\pv"';
dj'\c('(_('
CIV\L
40
""H/'L
dj{gpfldn&.
|
3(\
-"u
fioflf"'
5;24c'
\A/I'M&L'
(enese
e
!Jmnc'nm'l
e0ner
|in
e
\orl'enl.
O
-
(d)
(1
points)
What
is
the
meaning
of
alpha=.05?
r
-
\
o
U}
6
[N
o
LA
Wearerisking
a4
5
¢
Pfiébabn
'l'lj
o~
J'jfz
I
ere
¢,
6%
4")
Ob
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P{/
e
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H'o
.
