SCM 200 Final Exam Practice Questions

Question 1 of 130

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We should determine our objectives
of a study before we collect the data.

Select one of the following:

  • True
  • False

Question 2 of 130

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The numbers on a basketball jersey
are an example of qualitative data.

Select one of the following:

  • True
  • False

Question 3 of 130

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A cumulative relative frequency
totals to

Select one of the following:

  • 0%

  • 100%

  • The total number in your sample (n)

  • Cannot be determined without seeing the data

Question 4 of 130

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A data set that is skewed left
(negative) has most of the data
values on the left with a few data
values trailing off to the right.

Select one of the following:

  • True
  • False

Question 5 of 130

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A descriptive measure of a sample is
a parameter.

Select one of the following:

  • True
  • False

Question 6 of 130

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A stem and leaf plot is useful
because it

Select one of the following:

  • shows the distribution of the data

  • contains all the original data values

  • shows the distribution of the data AND contains all the original data values

  • it is a cumulative distribution

Question 7 of 130

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The first quartile of a distribution can
never be less than zero.

Select one of the following:

  • True
  • False

Question 8 of 130

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A boxplot is a good way to show the
mean of a data set.

Select one of the following:

  • True
  • False

Question 9 of 130

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Generally speaking, a stem and leaf
plot cannot be constructed from a
boxplot, but a boxplot can be
constructed from a stem and leaf
plot.

Select one of the following:

  • True
  • False

Question 10 of 130

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A population consists of the numbers 3,
8, 4. The mean and median, respectively,
are:

Select one of the following:

  • 5,8

  • 3,8

  • 4,5

  • 5,4

Question 11 of 130

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The median and mode are not
affected by outlier values.

Select one of the following:

  • True
  • False

Question 12 of 130

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Every data set has a mode.

Select one of the following:

  • True
  • False

Question 13 of 130

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One section of SCM 200 has 20 students,
another has 25 students, and a third
section has 55 students. A weighted
average of the number of students in
these sections is:

Select one of the following:

  • 25

  • 40.5

  • 33-1/3

  • 30

Question 14 of 130

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The following measures of variation
measure distance from the mean:

Select one of the following:

  • mean absolute deviation

  • variance

  • interquartile range

  • mean absolute deviation AND variance

Question 15 of 130

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Median is a measure of variability of
a data set.

Select one of the following:

  • True
  • False

Question 16 of 130

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Range is sensitive to all data values.

Select one of the following:

  • True
  • False

Question 17 of 130

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If we want the average of all the
deviations from the mean of a data
set, we can simply add the deviations
and divide by n.

Select one of the following:

  • True
  • False

Question 18 of 130

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The mean absolute deviation of the four
numbers 6, 14, 14, 14 is equal to

Select one of the following:

  • 0

  • 1

  • 2

  • 3

Question 19 of 130

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The units of a population mean absolute
deviation for a problem in which the units
are feet are

Select one of the following:

  • feet squared

  • the absolute value of feet

  • feet

  • no units. MAD is a relative measure

Question 20 of 130

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A population has three values: 3, 7, 5.
Find the population variance.

Select one of the following:

  • 0

  • 2.67

  • 1.63

  • 4

  • 2

Question 21 of 130

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A population consisted of the values 3, 7,
11, 11, 13. The population standard
deviation is equal to:

Select one of the following:

  • 12.8

  • 3.58

  • 16

  • 4

Question 22 of 130

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A sample consisting of the numbers 3, 6,
9 has a sample variance equal to 12.

Select one of the following:

  • True
  • False

Question 23 of 130

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The number of hours a child spent
watching TV over the past three days
was 15, 3, 9. Compute the sample
standard deviation.

Select one of the following:

  • 24

  • 6

  • 3

  • 2

Question 24 of 130

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A standard deviation can sometimes be
larger in numerical value than a variance.

Select one of the following:

  • True
  • False

Question 25 of 130

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The coefficient of variation computed
from the three sample values 25, 30, 35
would be equal to 20.

Select one of the following:

  • True
  • False

Question 26 of 130

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95% of data values that conform to a bellshaped
distribution lie within how many
standard deviations of the mean?

Select one of the following:

  • 0

  • 1

  • 2

  • 3

Question 27 of 130

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Student score = 70
Class mean = 80
Standard deviation = 5
The standard score is equal to 2.

Select one of the following:

  • True
  • False

Question 28 of 130

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Drawing an ace of spades and a three
of hearts are complementary events.

Select one of the following:

  • True
  • False

Question 29 of 130

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The items in a sample space must be

Select one of the following:

  • complementary

  • exhaustive

  • random

  • complementary AND exhaustive

Question 30 of 130

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When a probability is described in terms of the proportion of times that and event can be theoretically expected to occur, it is an example of relative frequency probability.

Select one of the following:

  • True
  • False

Question 31 of 130

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A couple plans to have 3 children. Assuming male-female births are equally likely, what is the probability that couple will have at least one girl among the three children?

Select one of the following:

  • 1/3

  • 2/3

  • 3/8

  • 7/8

Question 32 of 130

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When one throws a die 1,000 times
and determines that the probability of
obtaining a six on a die is one-sixth,
that person has used the theoretical
approach to probability.

Select one of the following:

  • True
  • False

Question 33 of 130

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A student has three pairs of socks in her
closet: one black pair, one red pair, and
one white pair. If she randomly selects
two socks from her closet, what is the
probability that they will be the same
color? (i.e. They will be a matching pair.)

Select one of the following:

  • 2/3

  • .20

  • .80

  • .75

Question 34 of 130

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The distribution of people’s heights
is an example of a discrete
probability distribution.

Select one of the following:

  • True
  • False

Question 35 of 130

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The sum of the probabilities in a
discrete probability distribution could
total 1.2.

Select one of the following:

  • True
  • False

Question 36 of 130

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Probabilities associated with random
variables must all be equal.

Select one of the following:

  • True
  • False

Question 37 of 130

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A quiz with 10 questions on it was given
to a class of 10 students. Each question
was worth one point and the results are
summarized below:
X = number of correct answers = 10, 9, 8,
7, 6, 5 or less, with frequencies f(X) = 3, 2,
1, 2, 2, 0 respectively.
The quiz score mean (expected value) is:

Select one of the following:

  • 8

  • 8.2

  • 9

  • 7.8

Question 38 of 130

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Find the variance of X for the following
probability distribution:
X P(X)
1 .4
3 .2
5 .4

Select one of the following:

  • 1.6

  • 4

  • 8/3

  • 3.2

Question 39 of 130

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Find the standard deviation of X for the
following probability distribution:
X P(X)
20 .50
30 .10
60 .40

Select one of the following:

  • 4.29

  • 18.4

  • 19

  • 361

Question 40 of 130

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Non-random samples involve
unequal probabilities.

Select one of the following:

  • True
  • False

Question 41 of 130

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For a random variable X to have a
binomial distribution, it is necessary that:

Select one of the following:

  • X represents the number of successes

  • the outcome of each trial is a success

  • the n trials are statistically dependent on eachother

  • X represents the number of successes AND the outcome of each trial is a success

Question 42 of 130

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A success in a binomial distribution
indicates that something positive has
occurred.

Select one of the following:

  • True
  • False

Question 43 of 130

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A weighted die is thrown. Success is
defined as getting an even number.
The probability of success is .55.
The probability of getting 2 even
numbers when throwing the die four
times is approximately .3675.

Select one of the following:

  • True
  • False

Question 44 of 130

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Samantha calls on 10 houses per day
selling Girl Scout cookies. Historically,
3 out of 4 customers buy cookies.
Assuming the binomial distribution
applies here, the variance of this
distribution is:

Select one of the following:

  • 1.875

  • 1.37

  • 7.5

  • 2.5

Question 45 of 130

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The standard deviation of the
distribution in the previous problem
is 1.37.

Select one of the following:

  • True
  • False

Question 46 of 130

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The standard normal distribution has
a mean of 1 and a standard deviation
of 0.

Select one of the following:

  • True
  • False

Question 47 of 130

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If X is a normal random variable with
a mean of 10 and a standard
deviation of 1/2, then X = 14 is 8
standard deviations away from the
mean.

Select one of the following:

  • True
  • False

Question 48 of 130

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Use the standard normal curve to
determine the probability that the random
variable z will fall between –0.04 and 0.44.
That is, find the following probability:
P(–0.04 < z < 0.44):

Select one of the following:

  • .4000

  • .4800

  • .1860

  • .1540

Question 49 of 130

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In the standard normal z-distribution,
the probability between z = –1 and z =
+1 is the same as the probability
between z = –0.5 and z = +1.5.

Select one of the following:

  • True
  • False

Question 50 of 130

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The lifetime of tires is normally distributed
with a mean of 50,000 miles and a standard
deviation of 3,000 miles. The warranty is
for 46,000 miles. What proportion of the
tires will fail after the warranty but before
52,000 miles? Indicate the interval below
that contains this probability.

Select one of the following:

  • .0000 to .2000

  • .2001 to .4000

  • .6001 to .8000

  • .8001 to 1.000

  • .4001 to .6000

Question 51 of 130

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When 6.3% of the data values fall
below a normally distributed random
variable, the correct z-value is -1.53.

Select one of the following:

  • True
  • False

Question 52 of 130

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Weights of cereal boxes are normally
distributed with a mean of 15 oz. and a
standard deviation of .5 oz. What is the
minimum weight a box could be and
remain in the top 14.46% of all boxes
filled?

Select one of the following:

  • 16.10 oz.

  • 14.47 oz.

  • 15.53 oz.

  • The answer cannot be determined with the information given

Question 53 of 130

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An unbiased estimator is:

Select one of the following:

  • no more likely to be above the
    population parameter than below.

  • always better than a biased
    estimator.

  • is a specific observed value of a
    statistic.

  • always better than a biased
    estimator AND is a specific
    observed value of a statistic.

Question 54 of 130

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The sample range is generally an
unbiased estimator of the population
range.

Select one of the following:

  • True
  • False

Question 55 of 130

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A disadvantage of a point estimate is
that we don’t know how accurate that
estimate is.

Select one of the following:

  • True
  • False

Question 56 of 130

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A sampling distribution is a
distribution of all possible values of a
statistic for a given sample size.

Select one of the following:

  • True
  • False

Question 57 of 130

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All standard deviations are standard
errors, but not all standard errors are
standard deviations.

Select one of the following:

  • True
  • False

Question 58 of 130

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If a random sample of size 16 is taken
from a skewed population whose mean is
equal to 360 and standard deviation is 36,
the standard error of the mean would
equal:

Select one of the following:

  • 9

  • 90

  • 10

  • 1/9

Question 59 of 130

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Given a population standard
deviation, as sample size increases,
standard error also increases.

Select one of the following:

  • True
  • False

Question 60 of 130

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For a test, the pop. mean score is 1100 and
the pop. st. dev. is 100. If the test is given
to 36 randomly selected individuals, what
is the probability that the sample mean will
lie between 1090 and 1122? After finding
the appropriate probability, indicate the
interval that includes this probability:

Select one of the following:

  • .0000 to .3000

  • .8501 to 1.000

  • .6001 to .7000

  • .3001 to .6000

  • .7001 to .8500

Question 61 of 130

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The Central Limit Theorem assures
us that the sampling distribution for
the sample mean approaches a
normal distribution as the sample
size increases, regardless of the
shape of the population distribution.

Select one of the following:

  • True
  • False

Question 62 of 130

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Records have shown that 15% of patients
are not satisfied with their care. A poll of
100 patients was conducted. What is the
probability that more than 18 patients will
not be satisfied with their care? After
finding the probability, indicate the
interval that includes this probability.

Select one of the following:

  • .0000 to .3000

  • .8501 to 1.000

  • .6001 to .7000

  • .3001 to .6000

  • .7001 to .8500

Question 63 of 130

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Confidence intervals specify
parameter values in advance.

Select one of the following:

  • True
  • False

Question 64 of 130

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In using the standard normal distribution
to establish a confidence interval for the
average number of hours that a light bulb
will last, what is the appropriate z-value to
use for a 34% level of confidence:

Select one of the following:

  • 0.17

  • 0.1331

  • 0.44

  • 0.99

Question 65 of 130

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Other things being equal, a 90%
confidence interval is wider than a
95% confidence interval.

Select one of the following:

  • True
  • False

Question 66 of 130

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A bank wants to determine mean waiting
time. It samples 100 customers and the
mean time is 6.9 minutes. Population
standard deviation is assumed to be 4
minutes. Find a 91.98% confidence
interval of mean waiting time:

Select one of the following:

  • 6.9 +/- 0.7

  • 6.9 +/- 0.92

  • 6.9 +/- 0.5

  • 6.9 +/- 1.75

Question 67 of 130

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A t-distribution with 5 degrees of
freedom has less area in the tails
than a standard normal distribution.

Select one of the following:

  • True
  • False

Question 68 of 130

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The following is true about the t-distribution:

Select one of the following:

  • like the standard normal distribution, there is only one t-distribution

  • the mean is 0

  • is determined by the parameter mu

  • approaches the standard normal as degrees of freedom become smaller

Question 69 of 130

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The important distinction between
the z-statistic and t-statistic is that z
is used for large sample sizes and t is
used for small sample sizes.

Select one of the following:

  • True
  • False

Question 70 of 130

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A confidence interval for a true population
mean is to be constructed from sample
data with size n = 23. The t-value to use
for setting a 90% level of confidence is:

Select one of the following:

  • 1.321

  • 1.319

  • 1.717

  • 1.714

  • 1.645

Question 71 of 130

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A random sample of 4 glass rods is tested
and reveals the following breaking
strength in pounds: 8, 4, 2, 6. Construct
an 80% confidence interval for the true
mean breaking strength:

Select one of the following:

  • (1.73, 8.27)

  • (3.74, 6.26)

  • (-.46, 10.46)

  • (2.89, 7.11)

Question 72 of 130

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Increasing the sample size, but using
the same level of confidence,
produces a confidence interval that
has a greater likelihood of containing
the parameter being estimated.

Select one of the following:

  • True
  • False

Question 73 of 130

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The mean age of viewers of TV shows
interests advertisers. A major network
believes that the mean age of viewers of a
show is more than 30. Many affiliate
stations claim the mean age is not greater
than 30. What is H0 for testing the major
network’s claim. Population mean mu is:

Select one of the following:

  • less than 30

  • greater than 30

  • not equal to 30

  • at least 30

  • at most 30

Question 74 of 130

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In testing the hypothesis below, a
statistician found that z = -0.44. What is
the p-value?
H0: mu = 10
Ha: mu does not equal 10

Select one of the following:

  • .67

  • .66

  • .56

  • .33

  • .17

Question 75 of 130

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In order to compute the p-value from
sample data, we need to know both
the alternative hypothesis and the
level of significance.

Select one of the following:

  • True
  • False

Question 76 of 130

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To test that the mean lifetime of light
bulbs is at least 900 hours (pop. normally
distributed and pop. st. dev. is 20), a
random sample of 25 bulbs is tested,
yielding a sample mean of 894 hours.
Find the p-value for the test. Indicate
which interval below contains the p-value.

Select one of the following:

  • .0301 to .1000

  • .5001 to 1.000

  • .2001 to .5000

  • .0000 to .0300

  • .1001 to .2000

Question 77 of 130

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If the p-value for a given hypothesis
testing problem is .055 and the level
of significance is .05, the null
hypothesis should be rejected.

Select one of the following:

  • True
  • False

Question 78 of 130

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In the following hypothesis test,
H0: mu = 4
Ha: mu > 4
the t-value was computed to be –2
and degrees of freedom are 11. The
correct p-value is .025 < p-value < .05.

Select one of the following:

  • True
  • False

Question 79 of 130

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Given an upper-tailed t-test for one
mean with 30 degrees of freedom and
the value of the test statistic computed
from the sample data t = 2.75 would
yield a p-value equal to .01.

Select one of the following:

  • True
  • False

Question 80 of 130

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Four runners were randomly sampled and
it was found they ran 23, 19, 23, and 23
miles per week. If we wish to test the
claim that the population mean running
distance is less than 25 miles per week,
what conclusion should be reached at the
1% level of significance?

Select one of the following:

  • Reject the claim by rejecting Ho

  • Accept the claim by rejecting Ho

  • Reject the claim by accepting Ho

  • Accept the claim by accepting Ho

Question 81 of 130

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In statistical process control, if the pvalue
is less than or equal to alpha, we
should conclude the process is under
control.

Select one of the following:

  • True
  • False

Question 82 of 130

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If mu = 40 pounds, sigma = 4 pounds, and
sample size is 36, the LCL and UCL on a
control chart for x would be:

Select one of the following:

  • 38 pounds, 42 pounds

  • 28 pounds, 52 pounds

  • 38.67 pounds, 41.33 pounds

  • 35 pounds, 45 pounds

Question 83 of 130

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A poll in a senatorial contest revealed that
40 out of 400 randomly selected people
indicated a preference for candidate A.
Find a 95.44% confidence interval for the
proportion of voters who favor candidate
A.

Select one of the following:

  • .07 to .13

  • .06 to .14

  • .05 to .15

  • .09 to .11

  • .38 to .42

Question 84 of 130

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A promoter is deciding whether to book a
new band. The promoter decides to do a
survey to try to estimate the true
proportion of individuals in the area who
will attend the concert. What should
sample size be to estimate the proportion
to within 5% with a 68.26% confidence
level? (Assume maximum error possible.)

Select one of the following:

  • 25

  • 100

  • 400

  • 200

Question 85 of 130

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In selecting a sample size to estimate
a population proportion, the sample
size will depend, among other things,
upon the level of confidence that is to
be used for the estimate.

Select one of the following:

  • True
  • False

Question 86 of 130

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A company is planning to test whether the
market share of a new product during its
first year on the market is more than 20
percent. The appropriate null hypothesis
would be that the market share percentage
is

Select one of the following:

  • greater than 20%

  • less than or equal to 20%

  • less than 20%

  • not equal to 20%

  • greater than or equal to 20%

Question 87 of 130

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A manufacturer claims that no more than
20% of all units will experience a failure
within the first 5 years. 100 purchasers
randomly selected were asked to report
failures. If 28 failures were reported, what
conclusion should be reached about the
manufacturer’s claim? alpha = 5%.

Select one of the following:

  • Accept the claim by rejecting Ho

  • Reject the claim by rejecting Ho

  • Accept the claim by accepting Ho

  • Reject the claim by accepting Ho

Question 88 of 130

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Assume for a given hypothesis testing
problem, the test statistic was computed
and led to a rejection of the null at alpha of
.01. Based on this information, we can
further conclude that since H0 was rejected
at the 1% level, then H0

Select one of the following:

  • Must be rejected at alpha of 10%

  • must be accepted at alpha of 10%

  • must be accepted at alpha of 5%

  • must be accepted at alpha of 5% and 10%

Question 89 of 130

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The t-test for n1 = 15 and n2 = 15 using
paired testing has

Select one of the following:

  • 14 degrees of freedom

  • 13 degrees of freedom

  • 29 degrees of freedom

  • 28 degrees of freedom

  • 30 degrees of freedom

Question 90 of 130

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A paired difference experiment produced
the following data: n = 30, xbar1 = 72, xbar2 = 75.5,
Dbar = -3.5, and SD squared = 17. SE(Dbar) is equal to:

Select one of the following:

  • -0.64

  • 0.64

  • 0.75

  • -0.75

  • 3.10

Question 91 of 130

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Assume a matched pairs test for a
mean difference with a two-tailed
alternative hypothesis and the
number of paired differences n = 4. If
the computed test statistic t = 2.353,
then the p-value would be equal to
.05.

Select one of the following:

  • True
  • False

Question 92 of 130

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An analyst is testing a new system to see if
it uses a different processing time than the
old system. The time for each in seconds
was recorded for 28 samples.
Old System: mean = 21.2, s = 3.2, n = 28
New System: mean = 24.3, s = 2.1, n = 28
Difference (Old – New): mean = – 3.1,
s = 1.4, n = 28
What is the appropriate statistical test?

Select one of the following:

  • Paired t-test for mean differences

  • Hypothesis test for one proportion

  • regression analysis

  • Independent t-test for mean differences

Question 93 of 130

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An analyst is testing a new system to see if
it uses a different processing time than the
old system. The time for each in seconds
was recorded for 28 samples.
Old System: mean = 21.2, s = 3.2, n = 28
New System: mean = 24.3, s = 2.1, n = 28
Difference (Old – New): mean = – 3.1,
s = 1.4, n = 28
What is the alternative hypothesis for the
question above?

Select one of the following:

  • Ha: muD = 0

  • Ha: MuD < 0

  • Ha: MuD > 0

  • Ha: MuD does not equal 0

Question 94 of 130

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In a simple linear regression analysis,
the p-value associated with a test of
the slope coefficient was equal to .026,
which would lead us to conclude that a
linear relationship exists between the
two variables at the 5% level of
significance.

Select one of the following:

  • True
  • False

Question 95 of 130

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An analyst is testing a new system to see if
it uses a different processing time than the
old system. The time for each in seconds
was recorded for 28 samples.
Old System: mean = 21.2, s = 3.2, n = 28
New System: mean = 24.3, s = 2.1, n = 28
Difference (Old – New): mean = – 3.1,
s = 1.4, n = 28
The correct t-value for the previous
question is:

Select one of the following:

  • 62

  • 11.72

  • -62

  • -11.72

Question 96 of 130

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An analyst is testing a new system to see if
it uses a different processing time than the
old system. The time for each in seconds
was recorded for 28 samples.
Old System: mean = 21.2, s = 3.2, n = 28
New System: mean = 24.3, s = 2.1, n = 28
Difference (Old – New): mean = – 3.1,
s = 1.4, n = 28
If the p-value for this test is less than .002
and alpha is .05, analysts would conclude
that

Select one of the following:

  • the old system uses more processing time

  • the old system uses less processing time

  • the systems use the same processing time

  • the system processing times are unequal

Question 97 of 130

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A doctor claims the average person is
more than 11 pounds overweight. To test
the claim, the difference between actual
and ideal weight of 36 randomly selected
people was calculated. The sample mean
and sample standard deviation were 14
and 5 pounds respectively. At alpha of 1%,
can we conclude the claim is true?

Select one of the following:

  • Yes, the claim is true by rejecting Ho

  • Yes, the claim is true by accepting Ho

  • No, the claim is not true by rejecting Ho

  • No, the claim is not true by accepting Ho

Question 98 of 130

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The difference between the
independent sample and paired
sample approach is that with the
independent sample approach, a
background variable's effect is
controlled by pairing.

Select one of the following:

  • True
  • False

Question 99 of 130

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In general, the paired samples
method is preferred over the
independent samples method.

Select one of the following:

  • True
  • False

Question 100 of 130

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The t-test for n1 = 15 and n2 = 7 using the
independent samples approach has
(assuming equal population variances)

Select one of the following:

  • 14 degrees of freedom

  • 6 degrees of freedom

  • 21 degrees of freedom

  • 20 degrees of freedom

  • 22 degrees of freedom

Question 101 of 130

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Given the following information about a
hypothesis test of the difference between
two means based on independent random
samples. (Assume normal distributions
with equal variances.) The correct pvalue
is between .005 and .01.
H0: μ1 – μ2 = 0
Ha: μ1 – μ2 ≠ 0
x1 = 16.32, x2 = 17.44,
s1squared = 4.3,
s2squared = 2.2,
n1 = 30, n2 = 32

Select one of the following:

  • True
  • False

Question 102 of 130

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The best statistic for pi1 - pi2 is p1 – p2.

Select one of the following:

  • True
  • False

Question 103 of 130

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For n1 = 70 and n2 = 100 from populations
1 and 2, the number of successes are 35
and 35 respectively. The estimate of the
difference between pi1 - pi2 is

Select one of the following:

  • 0.35

  • 0.15

  • 0.70

  • 0.50

  • 0.42

Question 104 of 130

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For n1 = 200 and n2 = 100 from
populations 1 and 2, the numbers of
successes are 35 and 25 respectively.
The value of the pooled sample
proportion p-hat is 0.20.

Select one of the following:

  • True
  • False

Question 105 of 130

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In an upper-tailed test of the difference
of two proportions, the z-value was
calculated to be 2.69. The p-value for
this test would then be .0036.

Select one of the following:

  • True
  • False

Question 106 of 130

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The purpose of a scatterplot is to
visually determine if a relationship
exists between two variables.

Select one of the following:

  • True
  • False

Question 107 of 130

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In using the regression model for
forecasting the next value (or an
individual value) of y, the prediction
interval will be

Select one of the following:

  • the same as the estimating interval

  • narrower than the estimating interval

  • wider than the estimating interval

  • wider or narrower, depending on the data

Question 108 of 130

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The coefficient of determination (R2) is
equal to 0.64, and the linear regression
equation which indicates an inverse
relationship between x and y is equal to
ŷ = 2 - .74x, then the correlation coefficient
must necessarily be equal to:

Select one of the following:

  • -.80

  • +.64

  • -.74

  • either -.80 or +.80

Question 109 of 130

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In a simple linear regression and
correlation problem, a correlation
coefficient of .80 means that 64% of
the variation in y can be explained by
x.

Select one of the following:

  • True
  • False

Question 110 of 130

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When R2 = 1, then Se = Sy.

Select one of the following:

  • True
  • False

Question 111 of 130

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A correlation coefficient of –1.0 would
imply that the standard error of the
estimate Se would necessarily be equal
to 0.

Select one of the following:

  • True
  • False

Question 112 of 130

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Standard error is measured in the units
of the x variable.

Select one of the following:

  • True
  • False

Question 113 of 130

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The range of a regression coefficient is
– 1 to + 1.

Select one of the following:

  • True
  • False

Question 114 of 130

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Standard deviation of height = 2.45
inches.
Standard deviation of weight = 23
pounds.
Correlation = .56
If we are predicting weight from height,
the regression coefficient is 5.26.

Select one of the following:

  • True
  • False

Question 115 of 130

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If ŷ = 15 + 10x, then the estimated value of
y when x = 5 is:

Select one of the following:

  • 25

  • 65

  • 10

  • 15

  • 55

Question 116 of 130

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When H0 is accepted in a regression
model, we conclude:

Select one of the following:

  • A linear relationship exists
    between x and y.

  • The x variable is statistically
    significant.

  • The x variable is not statistically
    significant.

  • A linear relationship exists
    between x and y AND the x
    variable is statistically significant.

Question 117 of 130

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Seasonality can be incorporated into
regression models with dummy
variables.

Select one of the following:

  • True
  • False

Question 118 of 130

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For the linear equation ŷ = 50 – 2x where y
is the number of items sold and x is the
price of the product in $, which is true?

Select one of the following:

  • The equation represents an inverse
    relationship between y and x.

  • The equation represents a positive
    relationship between y and x
    because the constant term 50 is
    greater than 0.

  • The slope of the line is – 2 dollars
    per each item sold.

  • The slope of the line is +50 dollars
    per each item sold.

Question 119 of 130

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If a correlation exists between y and x,
then necessarily either y causes x or x
causes y.

Select one of the following:

  • True
  • False

Question 120 of 130

Medal-premium 1

The advantage of multiple regression
over simple regression is that we can
change more than one variable at a
time.

Select one of the following:

  • True
  • False

Question 121 of 130

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If ŷ = 31 + 1.2x1 – 3.4x2 + 5x3, then the
estimated value of y when x1 = – 6, x2 = 3,
and x3 = 2 is:

Select one of the following:

  • 31.7

  • 25.4

  • 23.6

  • 38

Question 122 of 130

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The alternative hypothesis in a multiple
regression problem is that no linear
relationship exists between a given
independent variable and y.

Select one of the following:

  • True
  • False

Question 123 of 130

Medal-premium 1

The correlation coefficient between college
GPA and H.S. GPA is .70. The correlation
coefficient between college GPA and H.S.
rank is .60. Which of the following is true?

Select one of the following:

  • 70% of the variation in college GPA can
    be explained by H.S. GPA.

  • 60% of the variation in college GPA can
    be explained by H.S. GPA.

  • H.S. GPA is a better predictor of college
    GPA than H.S. rank.

  • There is an inverse relationship between
    H.S. GPA and College GPA.

Question 124 of 130

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Adding another variable to a regression
equation will make R2

Select one of the following:

  • decrease

  • increase

  • stay the same or increase

  • stay the same or decrease

  • increase, decrease, or stay the same

Question 125 of 130

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The purpose of R2 adjusted is to
discern the effect of adding a variable
to a model.

Select one of the following:

  • True
  • False

Question 126 of 130

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Adding another variable to a
regression equation will necessarily
make R2 adjusted increase.

Select one of the following:

  • True
  • False

Question 127 of 130

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It is possible for a variable to be
significant in multiple regression when
that same variable is not significant in
simple regression.

Select one of the following:

  • True
  • False

Question 128 of 130

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Stable environments are critical for
effective time series analysis.

Select one of the following:

  • True
  • False

Question 129 of 130

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Which of the following is not a component
of time series?

Select one of the following:

  • Seasonality

  • Cycle

  • Randomness

  • Trend

  • Contingency

Question 130 of 130

Medal-premium 1

The regression model based on annual
data for the last 20 years is
ŷ = 20.35 + 2.4x. The actual value of y
when x = 12 is 52. The value of the
forecasting error is:

Select one of the following:

  • 68.35

  • 16.35

  • 2.85

  • 49.15

  • 40

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SCM 200 Final Exam Practice Questions

mursham22
Quiz by , created almost 2 years ago

Quiz on SCM 200 Final Exam Practice Questions, created by mursham22 on 16/12/2014.

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