MBA 613 – MIDTERM EXAM 2025/2026
QUESTIONS AND ANSWERS 100% PASS
What is descriptive statistics? - ANS It summarizes the center, spread, and shape of data,
helping identify unusual values or patterns.
How does the mean compare to the median in right skewed data? - ANS Mean > Median
(long right tail)
How does the mean compare to the median in left skewed data? - ANS Mean < Median (long
left tail)
What is the interquartile range (IQR)? - ANS It is represents the spread of the middle 50% of
data.
How do you calculate the IQR? - ANS Q3 - Q1 or 75 Quartile - 25 Quartile
How do you identify outliers using IQR? - ANS Data points below Q1 - 1.5 × IQR or above Q3
+ 1.5 × IQR are potential outliers.
What is the purpose of a boxplot? - ANS Provides a visual summary of data distribution,
median, IQR, and outliers.
1 @COPYRIGHT 2025/2026 ALLRIGHTS RESERVED
,What do histograms show? - ANS Displays the distribution of data, indicating normality,
skewness, or bimodality.
Why are histograms useful? - ANS They reveal gaps, spikes, or distribution patterns that may
indicate data quality issues.
What is the importance of exploratory data analysis? - ANS It helps catch errors, outliers, and
guides the selection of modeling techniques.
What is the difference between normal and skewed distribution? - ANS Normal:
Symmetrical, bell-shaped curve, Skewed: Asymmetrical, with a tail on one side.
What is the shape of a skewed distribution? - ANS Asymmetrical, with a tail on one side.
What is the shape of a normal distribution? - ANS Symmetrical, bell-shaped curve
What is a z-score? - ANS Measures how many standard deviations a data point is from the
mean.
What does a positive z-score indicate? - ANS The data point is above the mean.
What does a negative z-score indicate? - ANS The data point is below the mean.
What is the empirical rule? - ANS About 68% of data falls within 1 StdDev, 95% within 2
StdDevs, and 99.7% within 3 StdDevs of the mean.
What is variance? - ANS It measures the average squared deviation from the mean.
What is the relationship between variance and StdDev? - ANS It is the square root of
variance.
2 @COPYRIGHT 2025/2026 ALLRIGHTS RESERVED
, What is covariance? - ANS It measures how two variables change together.
What is correlation? - ANS It measures the strength and direction of the relationship
between two variables.
How is correlation measured? - ANS With the correlation coefficient, ranging from -1 to 1.
What does a correlation of 0 mean? - ANS No linear relationship between variables.
What is the primary purpose of descriptive statistics? - ANS To summarize the center,
spread, and shape of data and identify unusual values or patterns that could impact analysis.
What does standard deviation measure? - ANS It measures how far each data point is from
the mean, on average.
What does a low standard deviation indicate? - ANS Values are tightly clustered around the
mean.
What does a high standard deviation indicate? - ANS Values are more widely spread out
from the mean.
What does it mean if the mean is greater than the median? - ANS The data is right-skewed,
with a long tail on the right.
What does it mean if the mean is less than the median? - ANS The data is left-skewed, with a
long tail on the left.
What is the purpose of calculating the IQR? - ANS To identify the range of the middle 50% of
data and flag potential outliers.
3 @COPYRIGHT 2025/2026 ALLRIGHTS RESERVED
QUESTIONS AND ANSWERS 100% PASS
What is descriptive statistics? - ANS It summarizes the center, spread, and shape of data,
helping identify unusual values or patterns.
How does the mean compare to the median in right skewed data? - ANS Mean > Median
(long right tail)
How does the mean compare to the median in left skewed data? - ANS Mean < Median (long
left tail)
What is the interquartile range (IQR)? - ANS It is represents the spread of the middle 50% of
data.
How do you calculate the IQR? - ANS Q3 - Q1 or 75 Quartile - 25 Quartile
How do you identify outliers using IQR? - ANS Data points below Q1 - 1.5 × IQR or above Q3
+ 1.5 × IQR are potential outliers.
What is the purpose of a boxplot? - ANS Provides a visual summary of data distribution,
median, IQR, and outliers.
1 @COPYRIGHT 2025/2026 ALLRIGHTS RESERVED
,What do histograms show? - ANS Displays the distribution of data, indicating normality,
skewness, or bimodality.
Why are histograms useful? - ANS They reveal gaps, spikes, or distribution patterns that may
indicate data quality issues.
What is the importance of exploratory data analysis? - ANS It helps catch errors, outliers, and
guides the selection of modeling techniques.
What is the difference between normal and skewed distribution? - ANS Normal:
Symmetrical, bell-shaped curve, Skewed: Asymmetrical, with a tail on one side.
What is the shape of a skewed distribution? - ANS Asymmetrical, with a tail on one side.
What is the shape of a normal distribution? - ANS Symmetrical, bell-shaped curve
What is a z-score? - ANS Measures how many standard deviations a data point is from the
mean.
What does a positive z-score indicate? - ANS The data point is above the mean.
What does a negative z-score indicate? - ANS The data point is below the mean.
What is the empirical rule? - ANS About 68% of data falls within 1 StdDev, 95% within 2
StdDevs, and 99.7% within 3 StdDevs of the mean.
What is variance? - ANS It measures the average squared deviation from the mean.
What is the relationship between variance and StdDev? - ANS It is the square root of
variance.
2 @COPYRIGHT 2025/2026 ALLRIGHTS RESERVED
, What is covariance? - ANS It measures how two variables change together.
What is correlation? - ANS It measures the strength and direction of the relationship
between two variables.
How is correlation measured? - ANS With the correlation coefficient, ranging from -1 to 1.
What does a correlation of 0 mean? - ANS No linear relationship between variables.
What is the primary purpose of descriptive statistics? - ANS To summarize the center,
spread, and shape of data and identify unusual values or patterns that could impact analysis.
What does standard deviation measure? - ANS It measures how far each data point is from
the mean, on average.
What does a low standard deviation indicate? - ANS Values are tightly clustered around the
mean.
What does a high standard deviation indicate? - ANS Values are more widely spread out
from the mean.
What does it mean if the mean is greater than the median? - ANS The data is right-skewed,
with a long tail on the right.
What does it mean if the mean is less than the median? - ANS The data is left-skewed, with a
long tail on the left.
What is the purpose of calculating the IQR? - ANS To identify the range of the middle 50% of
data and flag potential outliers.
3 @COPYRIGHT 2025/2026 ALLRIGHTS RESERVED
