midterm
A
company
claims
a
200%
decrease
in
engine
sludge
when
advertising
their
new
synthetic
oil.
You
conclude
a)
You
will
have
½
the
engine
sludge
you
had
with
your
previous
oil
b)
The
synthetic
oil
has
twice
the
life
of
competitors
c)
A
200%
decrease
does
not
make
sense
-
ANS-c)
A
200%
decrease
does
not
make
sense
A
Fox
News
opinion
poll
wanting
the
opinion
of
US
adults
on
the
state
of
the
economy.
It
surveyed
1,072
US
adults
chosen
from
a
list
of
registered
voters.
Identify
the
sampling
frame.
a)
All
US
adults
b)
List
of
registered
voters
c)
1,072
adults
surveyed
-
ANS-b)
List
of
registered
voters
A
Fox
News
opinion
poll
wanting
the
opinion
of
US
adults
on
the
state
of
the
economy.
It
surveyed
1,072
US
adults
chosen
from
a
list
of
registered
voters.
Using
a
list
of
registered
voters
for
their
sample
leaves
out
all
the
adults
who
are
not
registered
to
vote.
This
is
an
important
error
called
a)
Nonsampling
error
b)
Random
sampling
error
c)
Sampling
frame
d)
Undercoverage
-
ANS-d)
Undercoverage
A
Fox
News
surveyed
1,072
US
adults
chosen
from
a
list
of
registered
voters.
The
poll
had
to
call
several
thousand
individuals
before
they
got
response
from
the
1,072
that
participated.
We
would
say
this
poll
suffers
from
a)
Response
error
b)
Nonresponse
error
c)
Processing
error
d)
Undercoverage
-
ANS-b)
Nonresponse
error
A
good
observational
study
will
a)
Attain
statistical
significance
b)
Account
for
lurking
variables c)
Be
comparative
d)
(A)
and
(B)
e)
(B)
and
(C)
-
ANS-e)
(B)
and
(C)
A
large
problem
with
internet
surveys
that
is
difficult
to
control
for
is
a)
Nonresponse
error
b)
Response
errors
c)
Undercoverage
d)
Random
sampling
error
e)
(A)
and
(C)
-
ANS-e)
(A)
and
(C)
A
parameter
is
a)
Known
and
will
not
vary
from
sample
to
sample
b)
Unknown
and
will
not
vary
from
sample
to
sample
c)
Known
and
will
vary
from
sample
to
sample
d)
Unknown
and
will
vary
from
sample
to
sample
-
ANS-b)
Unknown
and
will
not
vary
from
sample
to
sample
A
poll
asking
a
sample
of
US
adults
results
in
58%
saying
they
favor
a
proposed
government
healthcare
program.
The
reported
margin
of
error
(for
95%
confidence)
is
2%.
Choose
the
correct
confidence
statement.
a)
We
are
95%
confident
that
between
56
and
60%
of
all
US
adults
favor
the
government
healthcare
program.
b)
We
are
95%
confident
that
between
56
and
60%
of
US
adults
in
the
sample
favor
the
government
healthcare
program.
-
ANS-a)
We
are
95%
confident
that
between
56
and
60%
of
all
US
adults
favor
the
government
healthcare
program.
A
poll,
conducted
February
1-3
before
Superbowl
XLV,
asked
1,072
randomly
selected
adults,
"Do
you
plan
on
watching
all,
most,
some,
or
none
of
the
Superbowl
this
Sunday?"
740
responded
they
would
watch
at
least
part
of
Superbowl
XLV.
Find
the
observed
proportion
(the
sample
proportion),
"p"
̂,
of
those
who
will
watch
at
least
part
of
the
Superbowl
XLV.
A)
1/1,072
B)
740/1,072
C)
1/740
D)
1/√1,072
E)
1/√740
-
ANS-B)
740/1,072 A
poll,
conducted
February
1-3
before
Superbowl
XLV,
asked
1,072
randomly
selected
adults,
"Do
you
plan
on
watching
all,
most,
some,
or
none
of
the
Superbowl
this
Sunday?"
740
responded
they
would
watch
at
least
part
of
Superbowl
XLV.
Using
the
quick
formula,
compute
the
margin
of
error
for
95%
confidence
A)
1/1,072
B)
740/1,072
C)
1/740
D)
1/√1,072
E)
1/√740
-
ANS-D)
𝟏
/√(
𝟏
,
𝟎𝟕𝟐
)
A
poorly
worded
question
on
a
survey
would
be
a
type
of
a)
Sampling
error
b)
Nonsampling
Error
c)
Undercoverage
d)Processing
error
-
ANS-b)
Nonsampling
Error
A
probability
sample
is
a)
Always
a
simple
random
sample
b)
Any
sample
chosen
using
chance
c)
Never
a
stratified
random
sample
-
ANS-b)
Any
sample
chosen
using
chance
A
purchaser
for
a
large
convenience
store
chain
wants
to
know
if
the
shipment
of
1,000,000
batteries
he
is
receiving
is
a
good
one.
He
randomly
selects
100
batteries
from
the
shipment
and
tests
their
charge.
2
of
the
batteries
did
not
have
a
full
charge.
Identify
the
parameter.
A)
1,000,000
batteries
in
the
shipment
B)
100
randomly
selected
batteries
C)
2%
=
the
percent
of
the
100
selected
batteries
that
do
not
have
a
full
charge
D)
percent
of
the
1,000,000
batteries
that
do
not
have
a
full
charge
-
ANS-D)
percent
of
the
1,000,000
batteries
that
do
not
have
a
full
charge
A
purchaser
for
a
large
convenience
store
chain
wants
to
know
if
the
shipment
of
1,000,000
batteries
he
is
receiving
is
a
good
one.
He
randomly
selects
100
batteries
from
the
shipment
and
tests
their
charge.
2
of
the
batteries
did
not
have
a
full
charge.
Identify
the
statistic.
A)
1,000,000
batteries
in
the
shipment
B)
100
randomly
selected
batteries
C)
2%
=
the
percent
of
the
100
selected
batteries
that
do
not
have
a
full
charge