Stats Final

Question 1 of 83

1

The value of a parameter may change as the sample value changes.

Select one of the following:

True
False

Explanation

Question 2 of 83

1

A type of research inference involves using a statistic to estimate a parameter

Select one of the following:

True
False

Explanation

Question 3 of 83

1

The value of a statistic is fixed

Select one of the following:

True
False

Explanation

Question 4 of 83

1

In theory, the value of a continuous variable may take any value in some interval of numbers

Select one of the following:

True
False

Explanation

Question 5 of 83

1

A random sample guarantees a representative sample

Select one of the following:

True
False

Explanation

Question 6 of 83

1

For an experiment, a researcher manipulates conditions under which observations are made

Select one of the following:

True
False

Explanation

Question 7 of 83

1

A random sample maximizes the probability of obtaining a representative sample

Select one of the following:

True
False

Explanation

Question 8 of 83

1

The science of statistics can be used to prove anything a researcher would like to prove

Select one of the following:

True
False

Explanation

Question 9 of 83

1

For an observational study, a researcher merely records values of the dependent variable. That is, the researcher does not manipulate conditions under which observations are made.

Select one of the following:

True
False

Explanation

Question 10 of 83

1

The value of a statistic may change as the sample changes

Select one of the following:

True
False

Explanation

Question 11 of 83

1

Boxplots are a graphical display of the 5-number summary

Select one of the following:

True
False

Explanation

Question 12 of 83

1

If two events A and B are disjoint, then A ∩ B = {0}

Select one of the following:

True
False

Explanation

Question 13 of 83

1

For the data set consisting of the four numbers -3, -2, -2, -5, a valid measure of spread for all the data will be <0

Select one of the following:

True
False

Explanation

Question 14 of 83

1

The sample mean x̄, is always the balance point of the relative frequency histogram for the data

Select one of the following:

True
False

Explanation

Question 15 of 83

1

The sample median x̃, is always the balance point of the relative frequency histogram of the data

Select one of the following:

True
False

Explanation

Question 16 of 83

1

A positive correlation between two quantitative variables X and Y implies that as one increases the other tends to decrease

Select one of the following:

True
False

Explanation

Question 17 of 83

1

A positive correlation between two quantitative variables X and Y implies that as one increases, the other tends to increase

Select one of the following:

True
False

Explanation

Question 18 of 83

1

If two events are disjoint, then A U B = ϕ

Select one of the following:

True
False

Explanation

Question 19 of 83

1

The probability of the sample space is less than 1 when the probability of all the events contained in the sample space is less than 1.

Select one of the following:

True
False

Explanation

Question 20 of 83

1

The Standard Normal Curve is always symmetric around 0

Select one of the following:

True
False

Explanation

Question 21 of 83

1

When two events A and B are independent, the
P (A and B) = P (A) X P (B)

Select one of the following:

True
False

Explanation

Question 22 of 83

1

When Z~ N (0, 1), then P (Z ≤ -1.34) = P (Z > 1.34)

Select one of the following:

True
False

Explanation

Question 23 of 83

1

When X~ N ( μ, σ), then x̄~ N ( μ, σ/√n)

Select one of the following:

True
False

Explanation

Question 24 of 83

1

When two events A and B are independent, then
P (A ∩ B) = P (A) + P (B)

Select one of the following:

True
False

Explanation

Question 25 of 83

1

The Rule of Thumb for independence when drawing without replacement from a population states when the sample size is ≤ 5% of the population size, we can assume the draws are independent

Select one of the following:

True
False

Explanation

Question 26 of 83

1

H0: μ = 0 is only rejected when the p-value is > 0.05

Select one of the following:

True
False

Explanation

Question 27 of 83

1

H1: μ ≠ 0 is only accepted when the p-value > 0.05.

Select one of the following:

True
False

Explanation

Question 28 of 83

1

Suppose a 95% confidence interval for a population mean μ is given by (-17.32, 13.1). Then there is a 5% chance that μ will fall outside this interval.

Select one of the following:

True
False

Explanation

Question 29 of 83

1

Suppose a 95% confidence interval for a population mean μ is given by (-17.32, 13.1). Then there is a 95% chance that μ will fall in this interval.

Select one of the following:

True
False

Explanation

Question 30 of 83

1

If the sampled population is normal, then the sampling distribution of x̄ is normal when based on a random sample.

Select one of the following:

True
False

Explanation

Question 31 of 83

1

The number of new projects started each month at a cancer research center for the last nine months are:
0, 6, 10, 10, 12, 12, 16, 30
The sample median x̃ for the data is given by:

Select one of the following:

10
11
12
10.5

Explanation

Question 32 of 83

1

The number of new projects started each month at a cancer research center for the last nine months are:
0, 6, 10, 10, 12, 12, 16, 30
The IQR for the above data is:

Select one of the following:

8
7
6
14

Explanation

Question 33 of 83

1

The number of new projects started each month at a cancer research center for the last nine months are:
0, 6, 10, 10, 12, 12, 16, 30
Based on our Rule of Thumb for outliers, the following holds:

Select one of the following:

There are no outliers
The minimum value is an outlier
The median value is an outlier
The maximum value is an outlier

Explanation

Question 34 of 83

1

Which of the following sets of numbers has the smallest possible variance?

Select one of the following:

7, 8, 9, 10
-12, -12, -12, -12
0, 0, 10, 10
20, 23, 23, 30

Explanation

Question 35 of 83

1

The variance of 11 measurements of newborn height's (measured in inches) is computed to be 4 with a sample mean height of 20.
The units for the sample mean are:

Select one of the following:

inches
square root inches
inches squared
no units, mean never has units

Explanation

Question 36 of 83

1

The variance of 11 measurements of newborn height's (measured in inches) is computed to be 4 with a sample mean height of 20.
The standard deviation of these measurements is:

Select one of the following:

16
2
4
8

Explanation

Question 37 of 83

1

The units for the variance are

Select one of the following:

inches
square root inches
inches squared
no units, variance never has units

Explanation

Question 38 of 83

1

Volunteers for a research study were divided into three groups. Group 1 listened to Western religious music, Group 2 listened to Western rock music, and Group 3 listened to Chinese religious music. The blood pressure of each volunteer was measured before and after listening to the music, and the change in blood pressure was recorded. The scatterplot is given below
What does the scatterplot suggest about the correlation between change in blood pressure and type of music?

Select one of the following:

It is strongly negative
It is strongly positive
It is first strongly negative and then strongly positive
None of the above

Explanation

Question 39 of 83

1

Volunteers for a research study were divided into three groups. Group 1 listened to Western religious music, Group 2 listened to Western rock music, and Group 3 listened to Chinese religious music. The blood pressure of each volunteer was measured before and after listening to the music, and the change in blood pressure was recorded. The scatterplot is given below
What could we do to explore the relationship between type of music and change in blood pressure?

Select one of the following:

See if blood pressure decreases as type of music increases by examining a scatterplot
Make a histogram of the change in blood pressure for all of the volunteers
Make side-by-side boxplots of the change in blood pressure, with a separate boxplot for each group
Do all of the above

Explanation

Question 40 of 83

1

Events A, B, and C represent all possible outcomes of an experiment. That is, the sample space is given by S= {A, B, C}.
Which of the following does not have to be true?

Select one of the following:

0 ≤ P(A) ≤1
0 ≤ P(B) ≤ 1
0 ≤ P(C) ≤ 1
P ({A, B, C}) =1
P(A) + P(B) + P(C) =1
P(A) = P(B) = P(C) = 1/3

Explanation

Question 41 of 83

1

A fair coin is tossed two times in succession and the following events are defined:
A: {Observes at least one head}
B: {Observe exactly two heads}
C: {Observe exactly one head}
The sample space for this experiment is given by:

Select one of the following:

{H, T}
{HH, HT, TH, TT}
{HH, TT}
{H-T}

Explanation

Question 42 of 83

1

A fair coin is tossed two times in succession and the following events are defined:
A: {Observes at least one head}
B: {Observe exactly two heads}
C: {Observe exactly one head}
Using classical assignment of probability, the P(C) is:

Select one of the following:

1/4
3/4
2/4
1

Explanation

Question 43 of 83

1

Three experimental groups representing fitness levels for a random sample of U.S. men aged 35-45 were determined. The following chart represents the boxplots for the variable resting heart rate:
Which experimental group has the largest IQR?

Select one of the following:

Experimental group 0
Experimental group 1
Experimental group 2
Unable to determine using boxplots

Explanation

Question 44 of 83

1

Which of the following recorded variables is continuous?

Select one of the following:

Town of residence of a randomly selected college student
Number of people, both adults and children, living in a randomly selected U.S. household
Total household income (number of dollars per year), before taxes, in 2010 of a randomly selected U.S. household
Age, in years, of a randomly selected U.S. college student

Explanation

Question 45 of 83

1

Which of the following recorded variables is categorical?

Select one of the following:

Size of town of residence, measured as "small" for sizes ≤ 70,000; or "large" for sizes > 70,000 for a randomly selected U.S. college student
Number of residents per household working outside the home for a randomly selected U.S. household
The number of residents for a randomly selected U.S household
Age, in years, of a randomly selected U.S. college student

Explanation

Question 46 of 83

1

Which of these variables is categorical?

Select one of the following:

The race time (in minutes) of a randomly selected participant in the 2013 New York City marathon
The number of animals within a randomly selected geographical area
Whether randomly selected competitors in a running contest win or lose
The total number of contests won by randomly selected competitors for the year 2012

Explanation

Question 47 of 83

1

Does ginkgo biloba enhance memory? In a study to find out, 100 adult subjects who take ginkgo biloba once a day were randomly selected and 100 adults who do not take ginkgo biloba were randomly selected. Each group was given a memory test. The average score for the ginkgo biloba group was 82.78 and for the no-ginkgo group the average score was 73.46
The population(s) of interest are:

Select one of the following:

All adults
All adults who take ginkgo biloba once a day; all adults who do not take ginkgo biloba
All adults who take ginkgo biloba once a day
none of the above

Explanation

Question 48 of 83

1

Does ginkgo biloba enhance memory? In a study to find out, 100 adult subjects who take ginkgo biloba once a day were randomly selected and 100 adults who do not take ginkgo biloba were randomly selected. Each group was given a memory test. The average score for the ginkgo biloba group was 82.78 and for the no-ginkgo group the average score was 73.46
The parameters of interest for this study are:

Select one of the following:

Whether a person take ginkgo biloba or not
the memory test scores
the average test score for all adults who take ginkgo biloba and for all adults who do not take ginkgo biloba
the percentage of adults who take ginkgo biloba and the percentage of adults who do not take ginkgo biloba

Explanation

Question 49 of 83

1

Does ginkgo biloba enhance memory? In a study to find out, 100 adult subjects who take ginkgo biloba once a day were randomly selected and 100 adults who do not take ginkgo biloba were randomly selected. Each group was given a memory test. The average score for the ginkgo biloba group was 82.78 and for the no-ginkgo group the average score was 73.46
The dependent variable for this study is given by:

Select one of the following:

whether a person take ginkgo biloba or not
the memory test scores
the average test scores for all adults who take ginkgo biloba and for all adults who do not take ginkgo biloba
the percentage of adults who take ginkgo biloba and the percentage of adults who do not take ginkgo biloba

Explanation

Question 50 of 83

1

Does ginkgo biloba enhance memory? In a study to find out, 100 adult subjects who take ginkgo biloba once a day were randomly selected and 100 adults who do not take ginkgo biloba were randomly selected. Each group was given a memory test. The average score for the ginkgo biloba group was 82.78 and for the no-ginkgo group the average score was 73.46
The statistics calculated for this study are:

Select one of the following:

the sample averages 82.78 and 73.46
the average test scores for all adults who take ginkgo biloba and for all adults who don't take ginkgo biloba
the percentage of adults who take ginkgo biloba and the percentage of adults who do not take ginkgo biloba
none of the above

Explanation

Question 51 of 83

1

Does ginkgo biloba enhance memory? In a study to find out, 100 adult subjects who take ginkgo biloba once a day were randomly selected and 100 adults who do not take ginkgo biloba were randomly selected. Each group was given a memory test. The average score for the ginkgo biloba group was 82.78 and for the no-ginkgo group the average score was 73.46
Is the claim "ginkgo biloba causes memory improvement" supported by this study?

Select one of the following:

Yes, because random samples were obtained and the average scores for the no-ginkgo group were lower
No, because memory test scores can only be recorded as a categorical variable
Yes, because there is evidence that the average memory test score for the population of ginkgo taking adults is higher than the average memory test score for the population of no-ginkgo taking adults
No, because this is an observational study with possible confounding factors, such as genetics

Explanation

Question 52 of 83

1

The Gallup survey organization obtained a random sample of 2,527 U.S. citizens. The proportion in the sample who favored a constitutional amendment that would define marriage as being between a man and a woman was 1289/2527 = 51%
The population of interest consists of:

Select one of the following:

All of the 2527 citizens sampled
All U.S. college students
All U.S. citizens who favor the amendment
All U.S. citizens

Explanation

Question 53 of 83

1

The Gallup survey organization obtained a random sample of 2,527 U.S. citizens. The proportion in the sample who favored a constitutional amendment that would define marriage as being between a man and a woman was 1289/2527 = 51%
The percentage of the 2527 citizens who favor the amendment is an example of:

Select one of the following:

parameter value
a statistic
census with respect to amendment
qualitative, continuous variable

Explanation

Question 54 of 83

1

The Gallup survey organization obtained a random sample of 2,527 U.S. citizens. The proportion in the sample who favored a constitutional amendment that would define marriage as being between a man and a woman was 1289/2527 = 51%
The dependent variable is:

Select one of the following:

a discrete quantitative variable
a categorical variable
a continuous quantitative variable
a discrete categorical variable

Explanation

Question 55 of 83

1

A study was conducted to determine the effect of a new low-density lipoprotein (LDL) cholesterol lowering drug compared to the currently prescribed drug. 5000 U.S. adults aged 45-65 with "high" LDL cholesterol (> 130 milligrams per deciliter (mg/dL)) were randomly selected. 2500 of the adults were randomly assigned to the new drug group and 2500 of the adults were randomly assigned to the control (currently prescribed) drug group. At the end of the 1-year study period, the average LDL cholesterol level for the 2500 patients in the new drug group was 112 mg/dL and the average LDL cholesterol level for the control drug group was 125 mg/dL.
What are the population(s) of interest for this study?

Select one of the following:

All U.S. adults age 45-65
All U.S. adults age 45-65 with high LDL cholesterol and all U.S. adults age 45-65 with normal LDL cholesterol
All U.S adults age 45-65 with high LDL cholesterol who take the new drug and all U.S. adults age 45-65 with high LDL cholesterol who take the control drug
All U.S. adults with high LDL cholesterol

Explanation

Question 56 of 83

1

A study was conducted to determine the effect of a new low-density lipoprotein (LDL) cholesterol lowering drug compared to the currently prescribed drug. 5000 U.S. adults aged 45-65 with "high" LDL cholesterol (> 130 milligrams per deciliter (mg/dL)) were randomly selected. 2500 of the adults were randomly assigned to the new drug group and 2500 of the adults were randomly assigned to the control (currently prescribed) drug group. At the end of the 1-year study period, the average LDL cholesterol level for the 2500 patients in the new drug group was 112 mg/dL and the average LDL cholesterol level for the control drug group was 125 mg/dL.
What is the dependent variable?

Select one of the following:

Drug, measured as taking new drug or control drug
age, measured in years
LDL cholesterol > 130 mg/dL
LDL cholesterol after 1-year, measure in mg/dL

Explanation

Question 57 of 83

1

A study was conducted to determine the effect of a new low-density lipoprotein (LDL) cholesterol lowering drug compared to the currently prescribed drug. 5000 U.S. adults aged 45-65 with "high" LDL cholesterol (> 130 milligrams per deciliter (mg/dL)) were randomly selected. 2500 of the adults were randomly assigned to the new drug group and 2500 of the adults were randomly assigned to the control (currently prescribed) drug group. At the end of the 1-year study period, the average LDL cholesterol level for the 2500 patients in the new drug group was 112 mg/dL and the average LDL cholesterol level for the control drug group was 125 mg/dL.
What type of variable is the dependent variable?

Select one of the following:

A quantitative, discrete variabel
A quantitative, continuous variable
A categorical, discrete variable
A categorical, continuous variable

Explanation

Question 58 of 83

1

A study was conducted to determine the effect of a new low-density lipoprotein (LDL) cholesterol lowering drug compared to the currently prescribed drug. 5000 U.S. adults aged 45-65 with "high" LDL cholesterol (> 130 milligrams per deciliter (mg/dL)) were randomly selected. 2500 of the adults were randomly assigned to the new drug group and 2500 of the adults were randomly assigned to the control (currently prescribed) drug group. At the end of the 1-year study period, the average LDL cholesterol level for the 2500 patients in the new drug group was 112 mg/dL and the average LDL cholesterol level for the control drug group was 125 mg/dL.
What type of variable is the independent variable drug?

Select one of the following:

A quantitative, discrete variable
A quantitative, continuous variable
A categorical, discrete variable
A categorical variable

Explanation

Question 59 of 83

1

A study was conducted to determine the effect of a new low-density lipoprotein (LDL) cholesterol lowering drug compared to the currently prescribed drug. 5000 U.S. adults aged 45-65 with "high" LDL cholesterol (> 130 milligrams per deciliter (mg/dL)) were randomly selected. 2500 of the adults were randomly assigned to the new drug group and 2500 of the adults were randomly assigned to the control (currently prescribed) drug group. At the end of the 1-year study period, the average LDL cholesterol level for the 2500 patients in the new drug group was 112 mg/dL and the average LDL cholesterol level for the control drug group was 125 mg/dL.
The statistics calculated for this study are:

Select one of the following:

The average LDL cholesterol levels for both the high and normal populations
The average LDL cholesterol levels given by 112 mg/dL and 125 mg/dL
The average LDL cholesterol level for all U.S. adults
Percent with "high" cholesterol for both the 2500 patients prescribed the new drug and the 2500 patients prescribed the control drug

Explanation

Question 60 of 83

1

A study was conducted to determine the effect of a new low-density lipoprotein (LDL) cholesterol lowering drug compared to the currently prescribed drug. 5000 U.S. adults aged 45-65 with "high" LDL cholesterol (> 130 milligrams per deciliter (mg/dL)) were randomly selected. 2500 of the adults were randomly assigned to the new drug group and 2500 of the adults were randomly assigned to the control (currently prescribed) drug group. At the end of the 1-year study period, the average LDL cholesterol level for the 2500 patients in the new drug group was 112 mg/dL and the average LDL cholesterol level for the control drug group was 125 mg/dL.
The parameters of interest in this study are:

Select one of the following:

The average LDL cholesterol levels for both the high and normal populations
The average LDL cholesterol levels for both the new drug and the control drug populations after one year of taking the respective drug
The average LDL cholesterol levels for all U.S. adults
Percent with "high" cholesterol in the population of adults age 45-65

Explanation

Question 61 of 83

1

A study was conducted to determine the effect of a new low-density lipoprotein (LDL) cholesterol lowering drug compared to the currently prescribed drug. 5000 U.S. adults aged 45-65 with "high" LDL cholesterol (> 130 milligrams per deciliter (mg/dL)) were randomly selected. 2500 of the adults were randomly assigned to the new drug group and 2500 of the adults were randomly assigned to the control (currently prescribed) drug group. At the end of the 1-year study period, the average LDL cholesterol level for the 2500 patients in the new drug group was 112 mg/dL and the average LDL cholesterol level for the control drug group was 125 mg/dL.
The research inference of interest is given by:

Select one of the following:

The average LDL cholesterol is lower when the new drug is administered
The new drug sample average LDL cholesterol < the control drug sample LDL cholesterol, thus estimate the new drug population average LDL cholesterol < the control drug population LDL cholesterol
The sample average LDL cholesterol < 130, thus estimate the population LDL cholesterol < 130
The new drug is effective for lowering LDL cholesterol

Explanation

Question 62 of 83

1

A study was conducted to determine the effect of a new low-density lipoprotein (LDL) cholesterol lowering drug compared to the currently prescribed drug. 5000 U.S. adults aged 45-65 with "high" LDL cholesterol (> 130 milligrams per deciliter (mg/dL)) were randomly selected. 2500 of the adults were randomly assigned to the new drug group and 2500 of the adults were randomly assigned to the control (currently prescribed) drug group. At the end of the 1-year study period, the average LDL cholesterol level for the 2500 patients in the new drug group was 112 mg/dL and the average LDL cholesterol level for the control drug group was 125 mg/dL.
The design of this study is given by:

Select one of the following:

An experiment without random assignment
An observational study without random assignment
An experiment with random assignment to groups
An observational study with random assignment to groups

Explanation

Question 63 of 83

1

The legal profession conducted a study to determine the percentage of cardiologists who had been sued for malpractice in the last five years. The sample was randomly chosen from a national directory of doctors.
What is the dependent variable of interest in this study?

Select one of the following:

The doctor's area of expertise
The number of doctors who are cardiologists
The responses: have been sued/have not been sued for malpractice in the last five years
All cardiologists in the directory

Explanation

Question 64 of 83

1

Ignoring twins and other multiple births, assume babies born at a hospital are independent events with the probability that a baby is a boy and the probability that a baby is a girl both equal to 0.5
What is the probability that the next two babies are of the same sex?

Select one of the following:

0.25
0.75
1.0
0.50

Explanation

Question 65 of 83

1

Ignoring twins and other multiple births, assume babies born at a hospital are independent events with the probability that a baby is a boy and the probability that a baby is a girl both equal to 0.5
Define the events A = { the next two babies are boys}, and
B = { the next two babies are girls}. What do we know about events A and B?

Select one of the following:

They are symmetric
They are complements
They are independent
None of the above

Explanation

Question 66 of 83

1

Draws made with replacement are:

Select one of the following:

independent
dependent
not independent
none of the above

Explanation

Question 67 of 83

1

Draws made without replacement are:

Select one of the following:

independent
dependent
not dependent
none of the above

Explanation

Question 68 of 83

1

In the last mayoral election in a large city, 47% of the adults over the age of 65 voted Republican. A researcher wishes to determine if the proportion of adults over the age of 65 in the city who plan to voted Republican in the next mayoral election has changed. Let p represent the proportion of the population of all adults over the age of 65 in the city who plan to vote Republican in the next mayoral election. In terms of p, the researcher should test which of the following null and alternative hypotheses?

Select one of the following:

Ho: p= 0.47 vs. H1: p< 00.47
Ho: p= 0.47 vs. H1: p≠ 0.47
Ho: p= 0.47 vs. H1: p> 0.47
none of the above

Explanation

Question 69 of 83

1

The resting pulse rate for all runners in the New York City marathon for 2013 has a mean of μ = 70 and standard deviation of σ = 3. Suppose 49 runners are randomly selected from this population.
The distribution of x̄, the sample average resting pulse rate, is given by:

Select one of the following:

x̄ ~ N (70, 3) by CLT
x̄ ~ N (3, 70) by CLT
x̄ ~ N (70, 3/7) by result (1)
x̄ ~ N (70, 3/7) by CLT

Explanation

Question 70 of 83

1

The resting pulse rate for all runners in the New York City marathon for 2013 has a mean of μ = 70 and standard deviation of σ = 3. Suppose 49 runners are randomly selected from this population.
Find the probability that the sample average pulse rate of the 49 runners exceeds 70.86.

Select one of the following:

0.9772
0.4772
0.3859
0.0228

Explanation

Question 71 of 83

1

The power of a test of hypotheses is defined as:

Select one of the following:

P(conclude H1| H1 is true)
P(conclude H1 | Ho is true)
P(conclude Ho | H1 is true)
P(conclude Ho | Ho is true)

Explanation

Question 72 of 83

1

You have measured the systolic blood pressure of a random sample of 80 employees of a large company located near you. You use the default confidence interval formula of a statistical software package to calculate a 95% confidence interval for the mean systolic blood pressure for all employees of this company ( denoted by μ). The calculated confidence interval is (122, 138)
What requirements are necessary for this confidence interval to be valid?

Select one of the following:

The sample mean equals the population mean
The sample was randomly selected from an approximately normal population
The population mean has an approximate normal distribution
A random sample and the sampling distribution of the sample mean given by x̄ ~ N (μ , σ/√80)

Explanation

Question 73 of 83

1

You have measured the systolic blood pressure of a random sample of 80 employees of a large company located near you. You use the default confidence interval formula of a statistical software package to calculate a 95% confidence interval for the mean systolic blood pressure for all employees of this company ( denoted by μ). The calculated confidence interval is (122, 138)
Which of the following statements gives a valid interpretation of the phrase "95% confident μ is in the interval (122, 138)?

Select one of the following:

95% of the population of employees have a systolic blood pressure between 122 and 138
The method used to obtain the interval has a 95% chance of producing and interval that contains the population mean and systolic blood pressure
The probability that the population mean blood pressure is between 122 and 138 is 0.95
Both B and C

Explanation

Question 74 of 83

1

Suppose the resting pulse rate for all runners in the 2015 New York City marathon a week after the event has a mean of μ = 70 and a standard deviation of σ = 3. Supposed 64 runners will be randomly selected from this population
The distribution of x̄, the sample average resting pulse rate, is given by:

Select one of the following:

x̄ ~ N (70, 3) by CLT
x̄ ~ N (3, 70) by CLT
x̄ ~ N (70, 3/8) because the sampled population is normal
x̄ ~ N (70, 3/8) by CLT

Explanation

Question 75 of 83

1

Suppose the resting pulse rate for all runners in the 2015 New York City marathon a week after the event has a mean of μ = 70 and a standard deviation of σ = 3. Supposed 64 runners will be randomly selected from this population
Find the probability that the sample average resting pulse rate of the 64 runners is less than 70.9375

Select one of the following:

0.9938
0.4522
0.5478
0.0062

Explanation

Question 76 of 83

1

Suppose that A and B are two independent events. The probability that event A occurs in 0.4 (i.e. P(A) = 0.4), and that B occurs is P(B) = 0.2. What is the probability that both A and B occur?

Select one of the following:

0.08
0.60
0.52
0.40

Explanation

Question 77 of 83

1

A random sample of size n = 36 is to be drawn from a population with μ = 500 and σ = 200. What is the probability that the sample mean exceeds 400?

Select one of the following:

0.6915
Approximately 0
0.3085
0.9987

Explanation

Question 78 of 83

1

The scores of individual students interested in majoring in a Health Science program on the American College Testing (ACT) Program Composite College Entrance Examination are normally distributed with a mean of 18.6 and standard deviation of 6.0.
Find the proportion of scores that are greater than 33.6

Select one of the following:

0.0062
0.9938
0.0228
0.8413

Explanation

Question 79 of 83

1

The scores of individual students interested in majoring in a Health Science program on the American College Testing (ACT) Program Composite College Entrance Examination are normally distributed with a mean of 18.6 and standard deviation of 6.0.
Find the proportion of scores falling in the interval [12.42, 31.2]

Select one of the following:

0.8234
0.1515
-0.8234
0.8306

Explanation

Question 80 of 83

1

The scores of individual students interested in majoring in a Health Science program on the American College Testing (ACT) Program Composite College Entrance Examination are normally distributed with a mean of 18.6 and standard deviation of 6.0.
Find the proportion of scores that are less than 4.02

Select one of the following:

0.0075
0.9925
0.9918
0.0082

Explanation

Question 81 of 83

1

The attached table provides data from "A Case-Control Study of the Effectiveness of Bicycle Safety Helmets in Preventing Facial Injury"
For the group that did not wear helmets, find the risk for facial injury

Select one of the following:

0.78
0.44
0.27
0.16

Explanation

Question 82 of 83

1

The attached table provides data from "A Case-Control Study of the Effectiveness of Bicycle Safety Helmets in Preventing Facial Injury"
For those who did not wear helmets, find the odds of facial injuries to non-facial injuries

Select one of the following:

0.78
0.44
0.43
0.16

Explanation

Question 83 of 83

1

The attached table provides data from "A Case-Control Study of the Effectiveness of Bicycle Safety Helmets in Preventing Facial Injury"
Find the odds ratio for facial injuries in the group that did not wear helmets to the group that did wear helmets

Select one of the following:

0.78
1.36
0.16
1.81

	Created by Madison Skeel almost 4 years ago

STAT 121- Fall 2021

Stats Final

Question 1 of 83

The value of a parameter may change as the sample value changes.

Select one of the following:

Explanation

Question 2 of 83

A type of research inference involves using a statistic to estimate a parameter

Select one of the following:

Explanation

Question 3 of 83

The value of a statistic is fixed

Select one of the following:

Explanation

Question 4 of 83

In theory, the value of a continuous variable may take any value in some interval of numbers

Select one of the following:

Explanation

Question 5 of 83

A random sample guarantees a representative sample

Select one of the following:

Explanation

Question 6 of 83

For an experiment, a researcher manipulates conditions under which observations are made

Select one of the following:

Explanation

Question 7 of 83

A random sample maximizes the probability of obtaining a representative sample

Select one of the following:

Explanation

Question 8 of 83

The science of statistics can be used to prove anything a researcher would like to prove

Select one of the following:

Explanation

Question 9 of 83

For an observational study, a researcher merely records values of the dependent variable. That is, the researcher does not manipulate conditions under which observations are made.

Select one of the following:

Explanation

Question 10 of 83

The value of a statistic may change as the sample changes

Select one of the following:

Explanation

Question 11 of 83

Boxplots are a graphical display of the 5-number summary

Select one of the following:

Explanation

Question 12 of 83

If two events A and B are disjoint, then A ∩ B = {0}

Select one of the following:

Explanation

Question 13 of 83

For the data set consisting of the four numbers -3, -2, -2, -5, a valid measure of spread for all the data will be <0

Select one of the following:

Explanation

Question 14 of 83

The sample mean x̄, is always the balance point of the relative frequency histogram for the data

Select one of the following:

Explanation

Question 15 of 83

The sample median x̃, is always the balance point of the relative frequency histogram of the data

Select one of the following:

Explanation

Question 16 of 83

A positive correlation between two quantitative variables X and Y implies that as one increases the other tends to decrease

Select one of the following:

Explanation

Question 17 of 83

A positive correlation between two quantitative variables X and Y implies that as one increases, the other tends to increase

Select one of the following:

Explanation

Question 18 of 83

If two events are disjoint, then A U B = ϕ

Select one of the following:

Explanation

Question 19 of 83

The probability of the sample space is less than 1 when the probability of all the events contained in the sample space is less than 1.

Select one of the following:

Explanation

Question 20 of 83

The Standard Normal Curve is always symmetric around 0

When two events A and B are independent, the
P (A and B) = P (A) X P (B)

When two events A and B are independent, then
P (A ∩ B) = P (A) + P (B)

The number of new projects started each month at a cancer research center for the last nine months are:
0, 6, 10, 10, 12, 12, 16, 30
The sample median x̃ for the data is given by:

The number of new projects started each month at a cancer research center for the last nine months are:
0, 6, 10, 10, 12, 12, 16, 30
The IQR for the above data is:

The number of new projects started each month at a cancer research center for the last nine months are:
0, 6, 10, 10, 12, 12, 16, 30
Based on our Rule of Thumb for outliers, the following holds:

The variance of 11 measurements of newborn height's (measured in inches) is computed to be 4 with a sample mean height of 20.
The units for the sample mean are:

The variance of 11 measurements of newborn height's (measured in inches) is computed to be 4 with a sample mean height of 20.
The standard deviation of these measurements is: