1. What is the purpose of data imputation?
A. To remove missing data from a dataset
B. To fill in missing values with estimates based on other data points
C. To create new features from existing ones
D. To transform data into a more manageable format
Answer: B) To fill in missing values with estimates based on other data
points
Rationale: Data imputation involves filling in missing values using
statistical techniques, such as using the mean, median, or regression
models to estimate the missing data points.
2. What does a box plot represent in data analysis?
A. Distribution of data
B. Relationship between two variables
C. Central tendency of data
D. Data points that deviate from the norm
Answer: A) Distribution of data
Rationale: A box plot visually represents the distribution of data by
displaying the median, quartiles, and potential outliers. It helps
summarize the data’s spread and central tendency.
,3. In a dataset, if the correlation coefficient between two variables is -
0.8, what does this imply?
A. The variables have no relationship.
B. There is a weak positive relationship.
C. There is a strong negative relationship.
D. The variables are perfectly correlated in the negative direction.
Answer: C) There is a strong negative relationship.
Rationale: A correlation coefficient of -0.8 indicates a strong negative
relationship, meaning that as one variable increases, the other tends to
decrease.
4. Which of the following is true about a uniform distribution?
A. All values in the distribution are equally likely to occur.
B. The distribution has one peak at the mean.
C. It has a U-shape with a high value at the extremes.
D. The distribution is skewed to the left or right.
Answer: A) All values in the distribution are equally likely to occur.
Rationale: In a uniform distribution, all outcomes have the same
probability of occurring, resulting in a flat distribution.
5. What type of data is best analyzed using a chi-square test?
A. Ordinal data
B. Continuous data
, C. Categorical data
D. Time-series data
Answer: C) Categorical data
Rationale: The chi-square test is used to analyze categorical data to
assess whether there is a significant association between two variables.
6. In a dataset, which of the following is a typical characteristic of a
bimodal distribution?
A. It has two peaks or modes.
B. It has a single peak or mode.
C. The data is evenly distributed across all values.
D. It is normally distributed with no skew.
Answer: A) It has two peaks or modes.
Rationale: A bimodal distribution has two distinct peaks or modes,
indicating two different values or ranges that are most common in the
dataset.
7. In a histogram, what do the height of the bars represent?
A. The total number of data points.
B. The number of data points within a specific range.
C. The percentage of data points above the mean.
D. The overall variance of the data.
Answer: B) The number of data points within a specific range.
A. To remove missing data from a dataset
B. To fill in missing values with estimates based on other data points
C. To create new features from existing ones
D. To transform data into a more manageable format
Answer: B) To fill in missing values with estimates based on other data
points
Rationale: Data imputation involves filling in missing values using
statistical techniques, such as using the mean, median, or regression
models to estimate the missing data points.
2. What does a box plot represent in data analysis?
A. Distribution of data
B. Relationship between two variables
C. Central tendency of data
D. Data points that deviate from the norm
Answer: A) Distribution of data
Rationale: A box plot visually represents the distribution of data by
displaying the median, quartiles, and potential outliers. It helps
summarize the data’s spread and central tendency.
,3. In a dataset, if the correlation coefficient between two variables is -
0.8, what does this imply?
A. The variables have no relationship.
B. There is a weak positive relationship.
C. There is a strong negative relationship.
D. The variables are perfectly correlated in the negative direction.
Answer: C) There is a strong negative relationship.
Rationale: A correlation coefficient of -0.8 indicates a strong negative
relationship, meaning that as one variable increases, the other tends to
decrease.
4. Which of the following is true about a uniform distribution?
A. All values in the distribution are equally likely to occur.
B. The distribution has one peak at the mean.
C. It has a U-shape with a high value at the extremes.
D. The distribution is skewed to the left or right.
Answer: A) All values in the distribution are equally likely to occur.
Rationale: In a uniform distribution, all outcomes have the same
probability of occurring, resulting in a flat distribution.
5. What type of data is best analyzed using a chi-square test?
A. Ordinal data
B. Continuous data
, C. Categorical data
D. Time-series data
Answer: C) Categorical data
Rationale: The chi-square test is used to analyze categorical data to
assess whether there is a significant association between two variables.
6. In a dataset, which of the following is a typical characteristic of a
bimodal distribution?
A. It has two peaks or modes.
B. It has a single peak or mode.
C. The data is evenly distributed across all values.
D. It is normally distributed with no skew.
Answer: A) It has two peaks or modes.
Rationale: A bimodal distribution has two distinct peaks or modes,
indicating two different values or ranges that are most common in the
dataset.
7. In a histogram, what do the height of the bars represent?
A. The total number of data points.
B. The number of data points within a specific range.
C. The percentage of data points above the mean.
D. The overall variance of the data.
Answer: B) The number of data points within a specific range.
