DA0-002 Visualization and Reporting Practice Question
A retail company has collected data on monthly advertising spend (in thousands of dollars) and corresponding sales (in thousands of dollars) over the past 12 months. The analyst creates a scatter plot to visualize the relationship between advertising spend and sales. The plot shows a cluster of points with a positive trend, but there is one extreme outlier where spend was $100,000 but sales were only $20,000. Upon investigation, the analyst discovers that the outlier is due to a data entry error: the sales figure should have been $200,000. The analyst wants to present the overall trend accurately in a meeting. Which course of action should the analyst take first?
Answer choices
Why each option matters
Answer the question above first, then reveal the full breakdown to understand why each option is right or wrong.
Correct answer & explanation
✓
Remove the outlier and recreate the scatter plot.
Since the outlier is due to a data entry error, the appropriate first step is to correct the data (change the sales figure to $200,000) or remove the outlier, then recreate the scatter plot. This ensures the visualization accurately reflects the true relationship. Option A is incorrect: a bar chart with binned averages would still be affected by the erroneous data point and would not show the individual relationship clearly. Option B is incorrect: adding a trend line to the current plot would still be influenced by the erroneous outlier, potentially distorting the trend. Option D is incorrect: a line chart is typically used for time series data, and this is not a time series; moreover, it would still include the outlier.
Answer analysis
Option-by-option breakdown
For each option: why learners choose it and why it is or isn't the right answer here.
- ✗
Use a bar chart to show average sales per advertising spend bin.
Why it's wrong here
Incorrect. Binning may hide the outlier but does not fix the data error, and bar charts are less effective for showing correlation.
- ✗
Add a trend line using linear regression to the current scatter plot.
Why it's wrong here
Incorrect. The trend line would be heavily skewed by the outlier, giving a misleading representation.
- ✓
Remove the outlier and recreate the scatter plot.
Why this is correct
Correct. Removing the erroneous data point ensures the scatter plot reflects the true relationship.
- ✗
Change the chart type to a line chart.
Why it's wrong here
Incorrect. A line chart implies a time sequence, but the data is not time-ordered; it pairs spend with sales arbitrarily.
Go deeper
Related to this question
About these practice questions
One of 986 original DA0-002 practice questions on Courseiva, each with a full explanation and wrong-answer analysis — not exam dumps or protected exam content. Learn why practice questions differ from exam dumps →
JA
Written by Johnson Ajibi, MSc IT Security
Senior Network & Security Engineer · founder of Courseiva
This DA0-002 practice question is part of Courseiva's free CompTIA certification practice question bank. Courseiva provides original exam-style practice questions with explanations, topic-based practice, mock exams, readiness tracking, and study analytics to help learners prepare for the DA0-002 exam.