DA0-001 Practice Test 25 — 15 Questions

Question 1

Refer to the exhibit. A stakeholder complains that the line chart exaggerates the changes in sales. What is the most likely cause?

Accepted Answer

The y-axis does not start at zero. Setting beginAtZero to false truncates the y-axis, making small changes appear larger.

Answer

There are too few data points

Answer

The data labels are incorrect

Answer

The chart type should be a bar chart

Question 2

Which THREE are best practices for designing a dashboard for executive consumption?

Accepted Answer

Ensure the dashboard is responsive for mobile devices. Options A, C, and E are correct. Prioritize key metrics (A), provide interactive filters (C), and ensure mobile responsiveness (E). Option B is wrong because daily updates may be too frequent and clutter the dashboard. Option D is wrong because summary views are more useful for executives.

Answer

Include detailed raw data tables for transparency

Answer

Use a separate chart for each metric to avoid clutter

Question 3

A company needs to visualize monthly sales revenue for the past five years to identify seasonal trends. Which chart type is most appropriate?

Accepted Answer

Line chart with months on the x-axis and revenue on the y-axis. Option B (Line chart) is correct because line charts are ideal for showing trends over time. Option A (Bar chart) could work but is less effective for continuous time series. Option C (Pie chart) is for proportions, not trends. Option D (Scatter plot) is for relationships between two variables.

Answer

Stacked bar chart showing each year as a segment

Answer

Scatter plot with revenue vs. month number

Answer

Pie chart for each year showing revenue distribution

Question 4

An analyst creates a dashboard with multiple visualizations. Which feature allows users to change the data displayed across all charts simultaneously?

Accepted Answer

Filter or slicer. Option D is correct because a filter (or slicer) can apply to multiple visuals. Option A is for limited data view. Option B is a chart type. Option C is dividing data into segments.

Answer

Linked chart

Answer

Drill-down

Answer

Data segmentation

Question 5

A business analyst wants to compare the proportion of total sales contributed by each product category in the current year. Which visualization is most suitable?

Accepted Answer

Pie chart. Option C is correct because a pie chart effectively shows parts of a whole when the number of categories is small. Option A is for trends. Option B is for distribution of a continuous variable. Option D is for relationships.

Answer

Scatter plot

Answer

Line chart

Answer

Histogram

Question 6

A logistics company has data on delivery times (continuous) and distance traveled (continuous). They want to visualize the relationship between these two variables. Which chart type is most appropriate?

Accepted Answer

Scatter plot. Option D is correct because scatter plots show the relationship between two continuous variables. Option A is for categorical comparisons. Option B is for trends over time. Option C is for frequency distribution.

Answer

Histogram

Answer

Bar chart

Answer

Line chart

Question 7

A data analyst is troubleshooting a map visualization that shows null values for some regions. Which TWO actions should the analyst take to resolve the issue?

Accepted Answer

Check that latitude and longitude fields are properly geocoded.. Option B is correct because improper geocoding is a common cause of null values in map visualizations. Option D is correct if the data source lacks region names or has mismatches. Option A is wrong because changing mark type does not fix missing data. Option C is wrong because removing color encoding hides the symptom but doesn't address the root cause. Option E is wrong because filtering out nulls may hide missing data issues instead of resolving them.

Answer

Add a filter to exclude null values.

Answer

Change the mark type from Map to Pie.

Answer

Remove the color encoding from profit.

Question 8

A dashboard designer needs to ensure that color choices are accessible to users with color vision deficiencies. Which practice should be followed?

Accepted Answer

Combine color with patterns or labels to convey information. Option C is correct because patterns or shapes provide alternative ways to distinguish data. Option A is wrong as relying only on hue is problematic. Option B is wrong because grayscale loses emphasis. Option D is wrong as specific colors like red-green are problematic for some.

Answer

Use a rainbow color palette to maximize differentiation

Answer

Convert all charts to grayscale

Answer

Use red and green to indicate positive and negative values

Question 9

A data analyst is creating a dashboard to display monthly sales trends for the past two years. The dataset includes monthly sales figures with seasonal fluctuations. The analyst wants to highlight both the overall trend and the seasonal patterns effectively. Which TWO chart types are most appropriate for this purpose? (Select two.)

Accepted Answer

Line chart. A line chart (A) clearly shows the overall trend over time, while a bar chart (C) allows easy comparison of monthly values, revealing seasonal peaks and troughs. A pie chart (B) is for parts of a whole and not suitable for trends. A scatter plot (D) is for correlations, not time series. A stacked area chart (E) can show cumulative trends but makes individual monthly comparisons difficult.

Answer

Stacked area chart

Answer

Scatter plot

Answer

Pie chart

Question 10

Which TWO actions will improve the readability of a bar chart showing quarterly sales across five regions?

Accepted Answer

Sort bars in descending order of sales. Options B and D are correct. Sorting bars by sales (B) helps compare values easily. Adding data labels (D) provides exact numbers. Option A is wrong because a 3D chart distorts perception. Option C is wrong because a vertical gridline pattern can clutter. Option E is wrong because a line chart on the same axis mixes data types.

Answer

Overlay a line chart showing cumulative sales

Answer

Add vertical gridlines for every bar

Answer

Switch to a 3D bar chart to add visual depth

Question 11

Which TWO are common mistakes when creating data visualizations?

Accepted Answer

Using excessive 3D effects that obscure data. Options A and D are correct. Truncated axis (A) can mislead, and excessive 3D effects (D) distort data. Option B is wrong because using a legend is good. Option C is wrong because sorting alphabetically can be helpful for lookup. Option E is wrong because color-blind friendly palettes are a best practice.

Answer

Sorting categories alphabetically in a bar chart

Answer

Choosing a color-blind friendly palette

Answer

Including a legend to identify chart elements

Question 12

A data analyst needs to visualize the relationship between two continuous variables, such as sales revenue and advertising spend, to identify potential correlation. Which chart type is most appropriate?

Accepted Answer

Scatter plot. Option C is correct because a scatter plot is specifically designed to show the relationship between two continuous variables and can reveal correlations, clusters, or outliers. Option A is wrong because bar charts compare discrete categories, not continuous relationships. Option B is wrong because line charts show trends over time, not correlation between two variables. Option D is wrong because pie charts show proportions of a whole.

Answer

Pie chart

Answer

Line chart

Answer

Bar chart

Question 13

A hospital's analytics team has created a dashboard for tracking patient wait times across departments. The dashboard uses a stacked bar chart showing average wait time per department, with each bar segmented by severity level (Low, Medium, High). However, management complains that it is difficult to compare total wait times across departments or identify which department has the highest average wait time. The data itself is accurate and complete. The analyst needs to redesign the visualization to address these concerns. Which course of action should the analyst take?

Accepted Answer

Change the chart to a grouped bar chart, with each department having separate bars for each severity level placed side-by-side.. Option A is correct. A grouped bar chart with bars for each department and separate bars for each severity level side-by-side allows direct comparison of total wait times across departments and easy identification of the department with the highest average wait time. Option B is incorrect because line charts are not suitable for categorical comparisons and would clutter the view with many lines. Option C is incorrect because a pie chart can only show proportions for a single category (e.g., total wait time per department) and does not convey severity levels. Option D is incorrect because a heat map shows patterns but does not clearly compare total wait times across departments; it is harder to read exact values.

Answer

Replace the stacked bar chart with multiple line charts, one per department.

Answer

Use a heat map with departments on one axis and severity levels on the other, with color intensity representing wait time.

Answer

Switch to a pie chart showing the proportion of total wait time each department contributes.

Question 14

A retail company operates 50 stores across the country. The data analyst has been asked to create a dashboard to visualize monthly sales trends over the past two years and compare the performance of the top 5 stores. The dataset includes store name, date, and daily sales amount. Initial exploration reveals that some stores have missing sales data for certain months due to system outages, and there are occasional extreme values caused by promotional events (e.g., Black Friday sales are 10x normal). The analyst needs to choose an appropriate visualization approach that accurately represents the trends and comparisons while handling these data quality issues. What should the analyst do to best meet the requirements?

Accepted Answer

Use a line chart for the overall monthly sales trend (aggregated across all stores) and a separate bar chart for the top 5 stores by total sales, with tooltips explaining outlier values.. Option C is correct because it combines a line chart for overall trend (aggregating all stores) and bar charts for top 5 stores, which allows comparison while handling missing data through aggregation. Tooltips can provide context for outliers. Option A is wrong because using separate line charts for each store becomes cluttered with 50 stores, and excluding outliers may omit valuable information about promotions. Option B is wrong because filtering out stores with missing data could remove important stores and distort the trend. Option D is wrong because a stacked bar chart with all 50 stores would be difficult to read and doesn't show trends over time effectively.

Answer

Use a line chart for each store's monthly sales and exclude outliers from the dataset.

Answer

Use a bar chart showing monthly sales for each month and filter out stores with missing data.

Answer

Use a stacked bar chart with all 50 stores, each bar representing a month.

Question 15

A data engineer needs to store logs from web servers that have varying fields. The logs are in JSON format. Which data type describes this JSON data?

Accepted Answer

Semi-structured data. JSON data with varying fields is classified as semi-structured data because it has organizational properties (key-value pairs, nested structures) but does not conform to a rigid schema like a relational table. The logs from web servers may have different fields per record, which is a hallmark of semi-structured data, as it allows flexibility while still being self-describing.

Answer

Binary data

Answer

Structured data

Answer

Unstructured data

DA0-001 Practice Test 25 — 15 Questions

Exhibit

DA0-001 Practice Test 25 — 15 Questions

Exhibit