1. Which of the following is a primary purpose of data visualization?
A. To confirm research hypotheses
B. To present data in a way that makes it easier to understand
C. To perform complex mathematical calculations
D. To reduce the size of large datasets
Answer: B) To present data in a way that makes it easier to understand
Rationale: Data visualization is used to make complex data more
comprehensible by visually presenting patterns, trends, and outliers in
the data.
2. Which of the following is a characteristic of qualitative data?
A. It can be measured and expressed numerically.
B. It represents categories or labels.
C. It is always continuous.
D. It has a defined order or ranking.
Answer: B) It represents categories or labels.
Rationale: Qualitative data refers to non-numeric data that represents
categories or labels, such as names, colors, or types.
3. What is the primary purpose of data normalization?
,A. To remove outliers from the data
B. To reduce the dimensionality of the dataset
C. To adjust the range of numerical values to a common scale
D. To eliminate duplicate values
Answer: C) To adjust the range of numerical values to a common scale
Rationale: Data normalization is the process of adjusting the values in a
dataset to a common scale, which improves the performance of machine
learning algorithms and ensures consistency across features.
4. What does the interquartile range (IQR) measure in a dataset?
A. The difference between the maximum and minimum values
B. The range of the middle 50% of the data
C. The average value of the dataset
D. The spread of all values in the dataset
Answer: B) The range of the middle 50% of the data
Rationale: The interquartile range (IQR) measures the spread of the
middle 50% of the data by calculating the difference between the first
and third quartiles.
5. What does the term "outlier" refer to in a dataset?
A. A value that lies outside the normal range of data points.
B. A value that is part of the central tendency of the data.
C. A value that appears in multiple categories.
, D. A value that is repeated within the dataset.
Answer: A) A value that lies outside the normal range of data points.
Rationale: An outlier is a data point that significantly differs from the
other observations, either much higher or much lower than the rest of
the data points.
6. Which of the following is true about skewed distributions?
A. A positively skewed distribution has a long tail on the left.
B. A negatively skewed distribution has a long tail on the right.
C. A positively skewed distribution has a long tail on the right.
D. Skewed distributions always follow a normal distribution.
Answer: C) A positively skewed distribution has a long tail on the
right.
Rationale: In a positively skewed distribution, the tail extends toward
higher values, making the mean greater than the median.
7. What type of sampling method is used when every member of the
population has an equal chance of being selected?
A. Stratified sampling
B. Random sampling
C. Convenience sampling
D. Cluster sampling
Answer: B) Random sampling
A. To confirm research hypotheses
B. To present data in a way that makes it easier to understand
C. To perform complex mathematical calculations
D. To reduce the size of large datasets
Answer: B) To present data in a way that makes it easier to understand
Rationale: Data visualization is used to make complex data more
comprehensible by visually presenting patterns, trends, and outliers in
the data.
2. Which of the following is a characteristic of qualitative data?
A. It can be measured and expressed numerically.
B. It represents categories or labels.
C. It is always continuous.
D. It has a defined order or ranking.
Answer: B) It represents categories or labels.
Rationale: Qualitative data refers to non-numeric data that represents
categories or labels, such as names, colors, or types.
3. What is the primary purpose of data normalization?
,A. To remove outliers from the data
B. To reduce the dimensionality of the dataset
C. To adjust the range of numerical values to a common scale
D. To eliminate duplicate values
Answer: C) To adjust the range of numerical values to a common scale
Rationale: Data normalization is the process of adjusting the values in a
dataset to a common scale, which improves the performance of machine
learning algorithms and ensures consistency across features.
4. What does the interquartile range (IQR) measure in a dataset?
A. The difference between the maximum and minimum values
B. The range of the middle 50% of the data
C. The average value of the dataset
D. The spread of all values in the dataset
Answer: B) The range of the middle 50% of the data
Rationale: The interquartile range (IQR) measures the spread of the
middle 50% of the data by calculating the difference between the first
and third quartiles.
5. What does the term "outlier" refer to in a dataset?
A. A value that lies outside the normal range of data points.
B. A value that is part of the central tendency of the data.
C. A value that appears in multiple categories.
, D. A value that is repeated within the dataset.
Answer: A) A value that lies outside the normal range of data points.
Rationale: An outlier is a data point that significantly differs from the
other observations, either much higher or much lower than the rest of
the data points.
6. Which of the following is true about skewed distributions?
A. A positively skewed distribution has a long tail on the left.
B. A negatively skewed distribution has a long tail on the right.
C. A positively skewed distribution has a long tail on the right.
D. Skewed distributions always follow a normal distribution.
Answer: C) A positively skewed distribution has a long tail on the
right.
Rationale: In a positively skewed distribution, the tail extends toward
higher values, making the mean greater than the median.
7. What type of sampling method is used when every member of the
population has an equal chance of being selected?
A. Stratified sampling
B. Random sampling
C. Convenience sampling
D. Cluster sampling
Answer: B) Random sampling
