WGU C207 LINEAR REGRESSION ANALYSIS
CERTIFICATION SCRIPT 2026 QUESTIONS
WITH SOLUTIONS GRADED A+
◍ Box Plot.
Answer: It is used to study the composition of a data set and examine the
distribution. Displays the 5-number summary as a central box with whiskers
that extend to the non-outlying data values
◍ Regression analysis was applied between sales data (y in $1,000s) and
advertising expenditures (x in $100s). A random sample of 17 observations
led to the following information:ANOVA df SS MS FRegression 225 Error
Total 300 Coefficients Standard Error t StatIntercept 12 Expenditure 1.8
0.2683The (positive) critical t value for testing whether x and y are related
at a 5% significance level isa. 1.753b. 2.131c. 1.746d. 2.120.
Answer: 2.131
◍ What is an incidence rate?.
Answer: The rate of NEW cases in a population divided by people at risk.
◍ Multicollineraity.
Answer: When two or more independent variables are highly (but not
perfectly) correlated with each other
◍ What does attribute data show?**..
Answer: Shows whether a result meets a requirement or not. It gives a
yes/no result.
◍ Simple Composite Index*.
Answer: An index based on more than one items/measures without
weighting any data more significantly than any other data. It improves
business performance!!!Example: suppose a Brand Equity index is created
, based on 5-point ratings of Quality, Value, and Uniqueness.Assume the
average summed rating score is 11.5 across 300 brandsWhat is the Simple
Composite "Brand Equity" Index for a brand with a summed rating score of
12.7?= (12..5) * 100 = 110.4 = 110 (or 10% above the average of
11.5)Do not need to know how to calculate.
◍ How to calculate NPS.
Answer: 1. How likely would you recommend this product 0-10?2. We
categorize respondents into 3 groups, Detractors (0-6), passives (7-8),
promoters (9-10). 3. NPS = The % Promoters - % of Detractors
◍ Two types of numerical data.
Answer: Interval and Ratio
◍ Results based management steps are:.
Answer: Resources and results.
◍ Shows how well a result meets the requirement.
Answer: variable
◍ Valid.
Answer: Founded on fact or evidence, does it actually measure what it is
trying to measure?
◍ Process approach.
Answer: A principle that lowers costs and shortens cycle times through the
effective use of resources.
◍ What percent of quality problems does Ishikawa claim the seven tools can
solve?.
Answer: 90% - 95%
◍ Results based management.
Answer: RBM uses results as the central measure of performanceTranslates
goals into resultsClearly defined accountability of resultsRequires
monitoring and self-assessment
◍ Skewness.
, Answer: How much the data "leans" to one side.
◍ Experimental Study.
Answer: All variables measured and changes are under the researchers
control.
◍ 5 questions asked about data management.
Answer: 1. Is the data relevant to your business2. Is the data complete, do
you have all the data3. Is the data accurate4. Is the data available and
assessable 5. Is the data timely and up to date
◍ Liner programming.
Answer: What production mix will provide the most profit given our
constraints? Keyword: Production Mix
◍ Flowchart.
Answer: Visual tool to understand a process
◍ What are the dependent variables?.
Answer: Variables changed by (that depend on) independent variables. They
are your PREDICTIONExample: You want to see if the amount of water a
tree gets predicts the height of the tree. The water is the independent
variable, the height of the tree is the dependent variable.
◍ Cyclicality.
Answer: Repetition in up and down patterns
◍ Cost-benefit analysis.
Answer: A study that compares the costs and benefits to society of providing
a public good.This is often done in the public sector. What is the benefit to
the public. The private sector is generally associated with costs.
◍ Define analytics.
Answer: Turning information into knowledge and developing fact based
strategies to gain a competitive edge.
◍ Reliable.
Answer: dependable
, ◍ z-score*.
Answer: The number of standard deviations a particular score is from the
meanYou use this when you want to see how new data relates or compares
to historical data. If a Z-score is 0, it indicates that the data point's score is
identical to the mean score. A Z-score of 1.0 would indicate a value that is
one standard deviation from the mean. Z-scores may be positive or negative,
with a positive value indicating the score is above the mean and a negative
score indicating it is below the mean.z-score= a specific score - the mean,
Then, you divide that number by the standard deviation.Any time you use
the mean and standard deviation to arrive at the probability of something
you are going to use Z-score.
◍ Alternative hypothesis.
Answer: The hypothesis that states there is a difference between two or
more sets of data.There is a difference
◍ Simple index number.
Answer: Price or quantity relative to a base period of 100Example: Big Mac
in 1968 is $1.60 and in 2014 is $4.80. (4.80/1.60) X 100 = 300. The price
has increased by 300% in that time period. A 1968 price index would be
(1.60/1.60) X 100=100Do not need to know how to calculate.
◍ Assume you have noted the following prices for academic textbooks and the
number of pages that each textbook contains:Book Pages (x) Price (y)A 500
$170 B 700 175C 750 190D 590 174E 540 172F 650 180G 480 160and you
obtained the following incomplete Excel results:ANOVA df SSRegression
395.607Residual Total 507.714 Coeffi-cients Standard Error t Stat
P-valueIntercept 126.80 11.4787 11.0467 0.0001Pages (x) 0.079 0.0189 a.
Compute the coefficient of determination, the coefficient of correlation, and
the standard error of estimate.b. Using the critical value (or p-value)
approach, perform the t test to determine whether the textbook price and the
number of pages are related. Let = 0.01.c. Find the 95% confidence interval
for the slope . d. Find the predicted price of a textbook with 620 pages.e.
Interpret the meaning of the value of the coefficient of determination..
CERTIFICATION SCRIPT 2026 QUESTIONS
WITH SOLUTIONS GRADED A+
◍ Box Plot.
Answer: It is used to study the composition of a data set and examine the
distribution. Displays the 5-number summary as a central box with whiskers
that extend to the non-outlying data values
◍ Regression analysis was applied between sales data (y in $1,000s) and
advertising expenditures (x in $100s). A random sample of 17 observations
led to the following information:ANOVA df SS MS FRegression 225 Error
Total 300 Coefficients Standard Error t StatIntercept 12 Expenditure 1.8
0.2683The (positive) critical t value for testing whether x and y are related
at a 5% significance level isa. 1.753b. 2.131c. 1.746d. 2.120.
Answer: 2.131
◍ What is an incidence rate?.
Answer: The rate of NEW cases in a population divided by people at risk.
◍ Multicollineraity.
Answer: When two or more independent variables are highly (but not
perfectly) correlated with each other
◍ What does attribute data show?**..
Answer: Shows whether a result meets a requirement or not. It gives a
yes/no result.
◍ Simple Composite Index*.
Answer: An index based on more than one items/measures without
weighting any data more significantly than any other data. It improves
business performance!!!Example: suppose a Brand Equity index is created
, based on 5-point ratings of Quality, Value, and Uniqueness.Assume the
average summed rating score is 11.5 across 300 brandsWhat is the Simple
Composite "Brand Equity" Index for a brand with a summed rating score of
12.7?= (12..5) * 100 = 110.4 = 110 (or 10% above the average of
11.5)Do not need to know how to calculate.
◍ How to calculate NPS.
Answer: 1. How likely would you recommend this product 0-10?2. We
categorize respondents into 3 groups, Detractors (0-6), passives (7-8),
promoters (9-10). 3. NPS = The % Promoters - % of Detractors
◍ Two types of numerical data.
Answer: Interval and Ratio
◍ Results based management steps are:.
Answer: Resources and results.
◍ Shows how well a result meets the requirement.
Answer: variable
◍ Valid.
Answer: Founded on fact or evidence, does it actually measure what it is
trying to measure?
◍ Process approach.
Answer: A principle that lowers costs and shortens cycle times through the
effective use of resources.
◍ What percent of quality problems does Ishikawa claim the seven tools can
solve?.
Answer: 90% - 95%
◍ Results based management.
Answer: RBM uses results as the central measure of performanceTranslates
goals into resultsClearly defined accountability of resultsRequires
monitoring and self-assessment
◍ Skewness.
, Answer: How much the data "leans" to one side.
◍ Experimental Study.
Answer: All variables measured and changes are under the researchers
control.
◍ 5 questions asked about data management.
Answer: 1. Is the data relevant to your business2. Is the data complete, do
you have all the data3. Is the data accurate4. Is the data available and
assessable 5. Is the data timely and up to date
◍ Liner programming.
Answer: What production mix will provide the most profit given our
constraints? Keyword: Production Mix
◍ Flowchart.
Answer: Visual tool to understand a process
◍ What are the dependent variables?.
Answer: Variables changed by (that depend on) independent variables. They
are your PREDICTIONExample: You want to see if the amount of water a
tree gets predicts the height of the tree. The water is the independent
variable, the height of the tree is the dependent variable.
◍ Cyclicality.
Answer: Repetition in up and down patterns
◍ Cost-benefit analysis.
Answer: A study that compares the costs and benefits to society of providing
a public good.This is often done in the public sector. What is the benefit to
the public. The private sector is generally associated with costs.
◍ Define analytics.
Answer: Turning information into knowledge and developing fact based
strategies to gain a competitive edge.
◍ Reliable.
Answer: dependable
, ◍ z-score*.
Answer: The number of standard deviations a particular score is from the
meanYou use this when you want to see how new data relates or compares
to historical data. If a Z-score is 0, it indicates that the data point's score is
identical to the mean score. A Z-score of 1.0 would indicate a value that is
one standard deviation from the mean. Z-scores may be positive or negative,
with a positive value indicating the score is above the mean and a negative
score indicating it is below the mean.z-score= a specific score - the mean,
Then, you divide that number by the standard deviation.Any time you use
the mean and standard deviation to arrive at the probability of something
you are going to use Z-score.
◍ Alternative hypothesis.
Answer: The hypothesis that states there is a difference between two or
more sets of data.There is a difference
◍ Simple index number.
Answer: Price or quantity relative to a base period of 100Example: Big Mac
in 1968 is $1.60 and in 2014 is $4.80. (4.80/1.60) X 100 = 300. The price
has increased by 300% in that time period. A 1968 price index would be
(1.60/1.60) X 100=100Do not need to know how to calculate.
◍ Assume you have noted the following prices for academic textbooks and the
number of pages that each textbook contains:Book Pages (x) Price (y)A 500
$170 B 700 175C 750 190D 590 174E 540 172F 650 180G 480 160and you
obtained the following incomplete Excel results:ANOVA df SSRegression
395.607Residual Total 507.714 Coeffi-cients Standard Error t Stat
P-valueIntercept 126.80 11.4787 11.0467 0.0001Pages (x) 0.079 0.0189 a.
Compute the coefficient of determination, the coefficient of correlation, and
the standard error of estimate.b. Using the critical value (or p-value)
approach, perform the t test to determine whether the textbook price and the
number of pages are related. Let = 0.01.c. Find the 95% confidence interval
for the slope . d. Find the predicted price of a textbook with 620 pages.e.
Interpret the meaning of the value of the coefficient of determination..
