1
WGU
WGU C784-STATISTICS MOD 5 EXAM
QUESTIONS AND ANSWERS UPDATED
(2024/2025) (VERIFIED ANSWERS)
If the relationship is linear, the strength of the correlation (linear
relationship) can be measured using a statistic called the - ANS ✓correlation
coefficient*.
A correlation coefficient is a number that falls somewhere from −1 to 1 .
A measure of the linear relationship between two attributes. The numerical
value demonstrates how closely the attributes vary together. Correlation
coefficients near -1 and +1 have strong linear correlation, while a
correlation coefficient near 0 has weak (or no) linear correlation.
A correlation coefficient at or near −1 represents a strong
____________________________________. A correlation coefficient at or near 1
represents a strong _____________________________. - ANS ✓negative linear
correlation
ie. When two variables move in opposite directions, in a linear fashion: as
the explanatory variable increases the response variable decreases.
positive linear correlation
ie. When two variables move in the same direction, in a linear fashion; the
explanatory variable increases the response variable increases.
To solve for the variation in data you take the ____________________ between the
maximum and minimum. - ANS ✓To solve for the variation in data you take the
difference between the maximum and minimum.
For the treatment group this is equal to 2.24−(−1.19)=3.43; for the placebo
group this is equal to 0.78−(−2.29)=3.07. 3.07 is less than 3.43,
WGU C784
, 2
WGU
Therefore the placebo group has less variation in its data.
A scatterplot is useful for which type of data?
a. Both variables are categorical.
b. One variable is categorical, one variable is quantitative.
c. Both variables are quantitative.
d. One variable is discrete, one variable is continuous. - ANS ✓c. Both
variables are quantitative.
True or False? A scatterplot always shows the explanatory variable on the
horizontal, or x-axis.
a. True
b. False - ANS ✓a. True on the X axis
(hint- X for explanatory)
1. A hospital is studying the effectiveness of two different heartburn
treatments (Treatment A and Treatment B) administered daily for a week.
The results are measured after one week of treatment, by placing a patient
into one of two groups: heartburn subsided OR heartburn remained. Which
numerical measure could be used to analyze the data?
a. Correlation coefficient
b. Five-number summary
c. Median
d. Conditional percentages - ANS ✓Correct. The answer is d. Both variables are
categorical (C→C) so we will use a two-way table. Therefore, our numerical
measure will be conditional percentages.
One of the challenges with young patients who suffer from acute asthma is
delivering medication during asthma attacks. Young patients often have
difficulty managing traditional delivery methods, such as inhalers. A study
was done to determine whether using a nebulizer to deliver medication
reduced the duration of asthma attacks in pediatric patients. Patients were
split into two groups. One group was given traditional inhalers as a method
to deliver medication during an attack. The other group was given the
nebulizer. The effectiveness of both delivery methods was measured by
comparing the time it took for an attack to subside. Which numerical
WGU C784
WGU
WGU C784-STATISTICS MOD 5 EXAM
QUESTIONS AND ANSWERS UPDATED
(2024/2025) (VERIFIED ANSWERS)
If the relationship is linear, the strength of the correlation (linear
relationship) can be measured using a statistic called the - ANS ✓correlation
coefficient*.
A correlation coefficient is a number that falls somewhere from −1 to 1 .
A measure of the linear relationship between two attributes. The numerical
value demonstrates how closely the attributes vary together. Correlation
coefficients near -1 and +1 have strong linear correlation, while a
correlation coefficient near 0 has weak (or no) linear correlation.
A correlation coefficient at or near −1 represents a strong
____________________________________. A correlation coefficient at or near 1
represents a strong _____________________________. - ANS ✓negative linear
correlation
ie. When two variables move in opposite directions, in a linear fashion: as
the explanatory variable increases the response variable decreases.
positive linear correlation
ie. When two variables move in the same direction, in a linear fashion; the
explanatory variable increases the response variable increases.
To solve for the variation in data you take the ____________________ between the
maximum and minimum. - ANS ✓To solve for the variation in data you take the
difference between the maximum and minimum.
For the treatment group this is equal to 2.24−(−1.19)=3.43; for the placebo
group this is equal to 0.78−(−2.29)=3.07. 3.07 is less than 3.43,
WGU C784
, 2
WGU
Therefore the placebo group has less variation in its data.
A scatterplot is useful for which type of data?
a. Both variables are categorical.
b. One variable is categorical, one variable is quantitative.
c. Both variables are quantitative.
d. One variable is discrete, one variable is continuous. - ANS ✓c. Both
variables are quantitative.
True or False? A scatterplot always shows the explanatory variable on the
horizontal, or x-axis.
a. True
b. False - ANS ✓a. True on the X axis
(hint- X for explanatory)
1. A hospital is studying the effectiveness of two different heartburn
treatments (Treatment A and Treatment B) administered daily for a week.
The results are measured after one week of treatment, by placing a patient
into one of two groups: heartburn subsided OR heartburn remained. Which
numerical measure could be used to analyze the data?
a. Correlation coefficient
b. Five-number summary
c. Median
d. Conditional percentages - ANS ✓Correct. The answer is d. Both variables are
categorical (C→C) so we will use a two-way table. Therefore, our numerical
measure will be conditional percentages.
One of the challenges with young patients who suffer from acute asthma is
delivering medication during asthma attacks. Young patients often have
difficulty managing traditional delivery methods, such as inhalers. A study
was done to determine whether using a nebulizer to deliver medication
reduced the duration of asthma attacks in pediatric patients. Patients were
split into two groups. One group was given traditional inhalers as a method
to deliver medication during an attack. The other group was given the
nebulizer. The effectiveness of both delivery methods was measured by
comparing the time it took for an attack to subside. Which numerical
WGU C784
