MCQ Collection
Data Visualization MCQs
Practice Data Visualization questions with answers and explanations.
Choose an option to check your answer.
A.
Very large observations are comparatively more probable
B.
All observations cluster tightly around the mean
C.
The variable becomes symmetric
D.
The support includes only negative values
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Correct Answer: A. Very large observations are comparatively more probable
Explanation:
A heavy tail decreases slowly, leaving more probability for extreme values.
This makes large events more common than under light-tailed models.
Choose an option to check your answer.
A.
It controls the amount of smoothing
B.
It sets the sample mean
C.
It determines the number of variables
D.
It labels missing values
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Correct Answer: A. It controls the amount of smoothing
Explanation:
Bandwidth determines how widely each observation's kernel is spread.
It has a much larger effect on the estimate than the exact kernel shape.
Choose an option to check your answer.
A.
A fitted density from a specified family with estimated parameters
B.
A density formed only by connecting histogram tops
C.
A list of raw observations
D.
A plot without a probability model
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Correct Answer: A. A fitted density from a specified family with estimated parameters
Explanation:
Parametric estimation assumes a family such as normal or exponential.
The sample is then used to estimate a limited set of parameters.
Choose an option to check your answer.
A.
The vertical spread changes across values of the predictor
B.
All points lie on one horizontal line
C.
The axes use different fonts
D.
The plot contains exactly two colors
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Correct Answer: A. The vertical spread changes across values of the predictor
Explanation:
Heteroscedasticity means conditional variability is not constant.
A funnel-shaped point cloud is a common visual sign.
Choose an option to check your answer.
A.
The preselected maximum probability of a Type I error under the testing procedure
B.
The observed sample mean
C.
The power of the test
D.
The confidence interval midpoint
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Correct Answer: A. The preselected maximum probability of a Type I error under the testing procedure
Explanation:
Alpha sets the rejection threshold before examining the result.
Common choices include 0.05, but context should guide the value.
Choose an option to check your answer.
A.
Different starts can converge to different local solutions
B.
It changes the raw observations
C.
It makes the algorithm supervised
D.
It guarantees the global optimum
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Correct Answer: A. Different starts can converge to different local solutions
Explanation:
The k-means objective is not convex over assignments and centroids together.
Multiple random starts improve the chance of finding a better solution.
Choose an option to check your answer.
A.
The ordering and timing of observations carry information
B.
Every variable must be categorical
C.
The sample must contain exactly one observation
D.
Time series cannot contain missing values
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Correct Answer: A. The ordering and timing of observations carry information
Explanation:
Time-series observations are indexed by time and are often dependent across periods.
Reordering them can destroy meaningful temporal structure.
Choose an option to check your answer.
A.
A pie chart of quartiles
B.
A log-log plot of tail probability against value
C.
A bar chart with alphabetic sorting only
D.
A normal probability table without values
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Correct Answer: B. A log-log plot of tail probability against value
Explanation:
Power-law relationships can appear approximately linear on logarithmic axes.
Departures from linearity indicate that a pure Pareto tail may be inadequate.
Choose an option to check your answer.
A.
An overly flat density
B.
A noisy density with many spurious peaks
C.
A perfectly normal curve
D.
A density with total area zero
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Correct Answer: B. A noisy density with many spurious peaks
Explanation:
Too little smoothing follows random sample fluctuations closely.
This high-variance estimate can suggest modes that are not real.
Choose an option to check your answer.
A.
When the data clearly have many irregular modes
B.
When a justified model offers stable estimation and interpretable parameters
C.
When no assumptions can be made
D.
When sample values are only category names
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Correct Answer: B. When a justified model offers stable estimation and interpretable parameters
Explanation:
A suitable parametric model can be efficient, concise, and easy to extrapolate.
Its assumptions must be checked rather than accepted automatically.
Choose an option to check your answer.
A.
A guarantee of causality
B.
A visual summary of the average relationship's form
C.
The exact value of every residual
D.
A replacement for the observed points
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Correct Answer: B. A visual summary of the average relationship's form
Explanation:
A smoother helps reveal trends that may be hidden by point noise.
It should be shown together with data and interpreted with uncertainty.
Choose an option to check your answer.
A.
Failing to reject a false null hypothesis
B.
Rejecting a true null hypothesis
C.
Calculating the wrong sample mean
D.
Using a two-sided alternative
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Correct Answer: B. Rejecting a true null hypothesis
Explanation:
A Type I error is a false positive conclusion under the test framework.
Its long-run probability is controlled by the significance level when assumptions hold.