Download MC REview ch 26

MC Chapter 26 –
Inference on
slope
Growth hormones are often used to increase the weight gain of chickens. In an
experiment using 15 chickens, five different doses of growth hormone (0, .2, .4, .8,
and 1.0 mg/kg) were injected into chickens (three for each dose) and the
subsequent weight gain was recorded. An experimenter plots the data and finds
that a linear relationship appears to hold. A computer output follows:
SOURCE
MODEL
ERROR
TOTAL
CONSTANT
DOSE
DF
1
13
14
SUM OF SQUARES
78.4083
125.7410
204.1493
COEFFICENT
3.7816
4.0416
MEAN SQUARE
78.4083
9.6723
StDev
1.1705
1.4195
F VALUE
8.11
T
3.23
2.85
p-value
.0137
p
0.0066
0.0137
1) The least-squares regression line is:
A)
ŷ = 4.04 + 3.78x
B)
ŷ = 3.23 + 2.85x
D)
ŷ = 3.78 + 4.04x
E)
ŷ = 1.17 + 1.42x
C)
ŷ = 2.85 + 3.23x
Growth hormones are often used to increase the weight gain of chickens. In an
experiment using 15 chickens, five different doses of growth hormone (0, .2, .4, .8,
and 1.0 mg/kg) were injected into chickens (three for each dose) and the
subsequent weight gain was recorded. An experimenter plots the data and finds
that a linear relationship appears to hold. A computer output follows:
SOURCE
MODEL
ERROR
TOTAL
CONSTANT
DOSE
DF
1
13
14
SUM OF SQUARES
78.4083
125.7410
204.1493
COEFFICENT
3.7816
4.0416
MEAN SQUARE
78.4083
9.6723
StDev
1.1705
1.4195
T
3.23
2.85
F VALUE
8.11
p-value
.0137
p
0.0066
0.0137
2) A 95% confidence interval for the slope is:
A) 4.04±1.96(1.42)
B) 4.04±1.77(1.42)
D) 3.78±1.77(1.17)
E) 3.78±2.16(1.17)
C) 4.04±2.16(1.42)
Growth hormones are often used to increase the weight gain of chickens. In an
experiment using 15 chickens, five different doses of growth hormone (0, .2, .4, .8,
and 1.0 mg/kg) were injected into chickens (three for each dose) and the
subsequent weight gain was recorded. An experimenter plots the data and finds
that a linear relationship appears to hold. A computer output follows:
SOURCE
MODEL
ERROR
TOTAL
CONSTANT
DOSE
DF
1
13
14
SUM OF SQUARES
78.4083
125.7410
204.1493
COEFFICENT
3.7816
4.0416
MEAN SQUARE
78.4083
9.6723
StDev
1.1705
1.4195
T
3.23
2.85
F VALUE
8.11
p-value
.0137
p
0.0066
0.0137
3) It is suspected that weight gain should increase with dose. An appropriate null
and alternate hypothesis to test the slope, the test statistic, and the p-value are:
A) H0:  = 0 Ha:  < 0; T = 2.85; p-value = .0069
B) H0 :   0 Ha:  < 0; T = 3.23; p-value = .0066
C) H0:  = 0 Ha:  > 0; T = 2.85; p-value = .0137
D) H0:  = 0 Ha:  > 0; T = 3.23; p-value = .0033
E) H0:  = 0 Ha:  > 0; T = 2.85; p-value = .0069
4) A large sample hypothesis test with σ known of a null hypothesis μ = 15
against the alternative hypothesis μ ≠ 15 results in the test statistic value of
z = 1.37. Assuming σ is known, the corresponding p-value is approximately
A) 0.0853
B) 0.1707
C) 0.4147
D) 0.8293
E) 0.9147
5) Given the data below, in conducting a test of association between
gender and grade, what is the expected count for the number of males
who earned a grade of B?
A
B
C
D
Male
10
32
25
6
Female
5
41
14
12
A) 32.5
B) 35.5
C) 36.8
D) 41.0
E) It cannot be determined
6) In a sample survey of 450 residents of a given community, 180 of them
indicated that they shop at the local mall at least once per monthly.
Construct a 95% confidence interval to estimate the true percentage of
residents who shop monthly at the local mall.
A) (0.355, 0.445)
B) (0.366, 0.434)
C) (0.377, 0.423)
D) (0.380, 0.420)
E) It cannot be determined from the information given
7) The table below shows the probability distribution for the number of
tails (X) in five tosses of a fair coin. What is μx?
X
0
1
2
3
4
5
P(X)
.03125
.15625
.3125
.3125
.15625
.03125
A) 2.0
B) 2.5
C) 3.0
D) 3.5
E) 4.0
8) A regression line includes the point (2, 14) and has the equation
ŷ = mx+4. If x and y are the sample means of the x and y values,
then
y=
A)
x 4
B)
5x  4
C)
x
D)
1
x
7
E)
x 2
9) Failing to reject a null hypotheses that is false can be characterized as
A) a Type I error
B) a Type II error
C) both a Type I and Type II error
D) A standard error of the mean
E) No error
10) The probability of a tourist visiting an area cave is 0.70 and of a tourist
visiting a nearby park is 0.60. The probability of visiting both places on the
same day is 0.40. The probability that a tourist visits at least one of these
two places is
A) 0.08
B) 0.28
C) 0.42
D) 0.90
E) 0.95
1)D
2) C
3) E
4) B
5) C
6) A
7) B
8) B
9) B
10) D