DA0-002 Practice Test 4 — 25 Questions

Question 1

A data analyst creates a scatter plot showing the relationship between advertising spend and revenue. The plot shows a strong positive correlation. Which of the following should the analyst include in the report to ensure accurate communication?

Choose an answer to begin — your selection is scored in the full session.

Accepted Answer

Include a note that correlation does not imply causation.. Correlation does not imply causation. It is important for the analyst to include this caveat to prevent misinterpretation of the relationship. Option B is incorrect because a bar chart is not appropriate for showing the relationship between two continuous variables. Option C is incorrect because removing outliers without justification can distort the analysis; outliers should be handled transparently. Option D is incorrect because while a trend line could be added, it is not mandatory and the question specifically asks for ensuring accurate communication, which is primarily about the correlation-causation warning.

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Replace the scatter plot with a bar chart.

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Remove any outliers from the plot.

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Add a trend line to the scatter plot.

Question 2

An analyst is presenting findings to stakeholders. Which TWO techniques effectively communicate uncertainty in data? (Choose TWO.)

Accepted Answer

Include confidence intervals.. Confidence intervals provide a range of values that likely contain the true population parameter, offering a clear measure of uncertainty around a point estimate. This technique is fundamental in inferential statistics and directly communicates the precision of the data, helping stakeholders understand the reliability of the findings.

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Use only point estimates.

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Remove all outliers from the data.

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State exact numbers without ranges.

Question 3

A company uses a NoSQL document database to store product catalogs. Each product document includes fields like product_id, name, category, and price. The operations team frequently queries by product_id and by category. Which type of NoSQL database is being used, and what should be created to optimize queries by category?

Accepted Answer

Document database; create an index on category. The question explicitly states a document database is used, and the operations team frequently queries by category. In a document database like MongoDB, creating an index on the category field optimizes these queries by allowing the database to quickly locate documents without scanning every document in the collection. This is the standard approach for improving query performance on non-primary-key fields in document stores.

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Key-value store; create a secondary index on category

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Graph database; create a relationship between products

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Wide-column store; create a column family for category

Question 4

A data analyst needs to present the correlation between advertising spend and website traffic. Which chart type is most appropriate?

Accepted Answer

Scatter plot. A scatter plot is the most appropriate chart type for visualizing the correlation between two continuous variables, such as advertising spend and website traffic. It displays individual data points on a Cartesian plane, allowing the analyst to assess the strength, direction, and form of the relationship (e.g., linear, non-linear, or no correlation). This aligns with the DA0-001 objective of selecting the correct visualization for bivariate analysis.

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Bar chart

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Line chart

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Pie chart

Question 5

A data engineer is designing a data warehouse for a multinational corporation. The company has sales data from different regions with varying currencies and date formats. To ensure consistency, which data concept should be applied to standardize the data before loading into the warehouse?

Accepted Answer

Data transformation. Data transformation is the correct concept because it involves converting data from source formats (e.g., different currencies and date formats) into a consistent, standardized format before loading into the data warehouse. This process includes applying conversion rules, such as using ISO 8601 for dates and a single base currency (e.g., USD) with exchange rate tables, ensuring uniformity across all regional data. Without transformation, the warehouse would contain incompatible data types, breaking referential integrity and analytical queries.

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Data cleansing

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Data profiling

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Data masking

Question 6

A logistics company is analyzing truck delivery times. Which variable is discrete?

Accepted Answer

Number of stops. A discrete variable is one that takes on a countable number of distinct values, often integers. The number of stops a truck makes is a count (e.g., 0, 1, 2, 3) and cannot be a fraction, making it a classic discrete variable in data analysis.

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Time taken in hours

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Fuel consumption in liters

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Distance traveled

Question 7

Which TWO of the following chart types are appropriate for showing the distribution of a continuous variable? (Choose 2.)

Accepted Answer

Box plot. A box plot is correct because it visually summarizes the distribution of a continuous variable through its five-number summary (minimum, first quartile, median, third quartile, maximum), clearly showing spread, central tendency, and potential outliers. This makes it ideal for distribution analysis in data visualization contexts like the DA0-001 exam.

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Bar chart

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Pie chart

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Line chart

Question 8

A data analyst is comparing characteristics of structured and unstructured data. Which TWO of the following are characteristics of structured data? (Choose two.)

Accepted Answer

Data is stored in predefined schemas. Structured data is organized into predefined schemas, such as tables with rows and columns, which enforce a consistent data format and relationships. This rigid structure allows structured data to be easily queried using SQL, as SQL is designed to operate on relational database management systems (RDBMS) that rely on these schemas. Option C is correct because a predefined schema is a defining characteristic of structured data, enabling efficient storage, retrieval, and integrity constraints.

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Data is typically stored as raw text

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Data lacks a fixed format

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Data often requires NoSQL databases for storage

Question 9

An analyst finds that a key metric drops significantly after a data pipeline update. How should the analyst proceed?

Accepted Answer

Compare data before and after update to identify discrepancies. The first step in diagnosing a sudden metric drop after a pipeline update is to perform a controlled comparison of pre- and post-update data. This involves validating data schemas, row counts, and distribution statistics to pinpoint whether the update introduced a transformation error, a filtering issue, or a data type mismatch. Without this comparison, the analyst cannot determine if the drop is due to a genuine data change or a pipeline defect.

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Assume it's a seasonal effect

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Revert the pipeline immediately

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Document the drop and report it

Question 10

When designing a report for executive leadership, which aspect is most important?

Accepted Answer

High-level summaries with key insights. Executive leadership requires actionable insights, not raw data. High-level summaries with key insights (Option D) allow leaders to quickly grasp trends, make decisions, and align with business goals without getting bogged down in technical details. This aligns with the DA0-001 objective of communicating data insights effectively to non-technical stakeholders.

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Detailed technical notes

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Raw data tables

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All raw SQL queries

Question 11

A data analyst is preparing a presentation for executive leadership. The analyst wants to highlight the correlation between marketing spend and revenue over the past year. Which visualization type is most appropriate for showing this relationship?

Accepted Answer

Scatter plot. A scatter plot is the most appropriate visualization for showing the relationship between two continuous variables—marketing spend and revenue—because it plots individual data points on an X-Y axis, allowing the analyst to visually assess correlation, trends, and outliers. This directly supports the goal of highlighting correlation, as the pattern of points (e.g., upward slope) indicates the strength and direction of the relationship.

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Pie chart

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Bar chart

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Histogram

Question 12

A data team is preparing a quarterly business review for the CEO. The report must include both high-level summaries and the ability for the CEO to drill down into specific departments. Which reporting technique best meets this requirement?

Accepted Answer

An interactive dashboard with drill-down capabilities.. An interactive dashboard with drill-down capabilities (Option B) is the correct choice because it directly addresses the requirement for both high-level summaries and the ability to explore specific departments. Dashboards allow the CEO to view aggregated KPIs at a glance and then click through to detailed views for each department, providing a seamless, user-driven exploration experience without switching between separate reports or slides.

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A slide deck with one slide per department.

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A static PDF with a summary page and appendices.

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A data dump in Excel with filters.

Question 13

A data analytics team has created a report for stakeholders. The report includes complex statistical terms and raw data tables. Stakeholders are confused and ask for clarification. Which of the following should the team do to improve communication?

Accepted Answer

Simplify the report by using clear visualizations and plain language summaries.. Effective data communication requires tailoring the message to the audience. By replacing complex statistical terms and raw data tables with clear visualizations and plain language summaries, the team makes insights accessible to stakeholders who may lack technical expertise, directly addressing the confusion.

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Schedule a follow-up meeting to explain each term individually.

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Provide a glossary of statistical terms and keep the report as is.

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Remove all data and only give conclusions.

Question 14

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.

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Binary data

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Structured data

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Unstructured data

Question 15

A data analyst is preparing a report to present to a mixed audience of technical and non-technical stakeholders. Which THREE techniques should the analyst use to ensure effective communication? (Choose three.)

Accepted Answer

Tailor the narrative to address different concerns. Tailoring the narrative to address different concerns ensures that both technical and non-technical stakeholders receive relevant insights. For non-technical audiences, the analyst should focus on business impact and high-level trends, while for technical audiences, deeper data nuances can be included. This approach aligns with the DA0-001 domain of Communicating Data Insights, where audience analysis is critical for effective data storytelling.

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Use only one chart type for consistency

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Use technical jargon to demonstrate expertise

Question 16

A data analyst runs the Python code shown. What is the result of executing this code?

Accepted Answer

It reads the data, adds a calculated column, and shows the first 5 rows. The code reads a CSV file into a pandas DataFrame, then creates a new column 'total' by summing columns 'col1' and 'col2'. Finally, `head()` returns the first 5 rows. Option A correctly describes this sequence of operations.

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It throws an error because 'total' column already exists

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It reads the data and displays all rows

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It reads the data and displays summary statistics

Question 17

After a marketing campaign, sales increased by 15%. The analyst wants to understand which customer segment contributed most to the increase. Which type of analysis is this?

Accepted Answer

Diagnostic analysis. Diagnostic analysis is used to understand the root cause of an event or change. In this scenario, the analyst already knows sales increased by 15% and wants to determine which customer segment drove that increase, which is a classic diagnostic question. This type of analysis goes beyond describing what happened to explain why it happened.

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Predictive analysis

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Prescriptive analysis

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Descriptive analysis

Question 18

A data analyst is analyzing survey responses where respondents rated satisfaction on a scale of 1-5. The analyst wants to visualize the distribution of responses. Which chart type is most appropriate?

Accepted Answer

Histogram. A histogram is the most appropriate chart for visualizing the distribution of a single discrete variable, such as satisfaction ratings on a 1-5 scale. It groups the responses into bins (each rating value) and displays the frequency of each bin using bars, clearly showing the shape, central tendency, and spread of the data.

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Box plot

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Scatter plot

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Line chart

Question 19

A data analyst is performing data cleaning. Which THREE steps are part of this process? (Choose three.)

Accepted Answer

Correcting inconsistent data. Correcting inconsistent data (Option A) is a core data cleaning step because it ensures that values follow a consistent format, such as standardizing date formats (e.g., 'MM/DD/YYYY' vs 'DD-MM-YYYY') or fixing capitalization (e.g., 'USA' vs 'usa'). This process directly addresses data quality issues that arise from human entry errors or system differences, making the dataset reliable for analysis.

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Normalization

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Feature engineering

Question 20

A data analyst at a marketing firm is creating a weekly performance report for the marketing team. The report includes metrics like click-through rates, conversion rates, and cost per acquisition. The team prefers a quick overview of the week's performance to identify trends and make decisions in their Monday morning meeting. The meeting is only 30 minutes, and the team has limited time to review data. The analyst wants to provide a report that is concise and actionable. What format should the analyst use?

Accepted Answer

A one-page executive summary with key metrics highlighted.. A one-page executive summary with key metrics highlighted provides the marketing team with a concise, actionable overview that can be quickly reviewed in a 30-minute meeting. This format aligns with the requirement for a quick overview to identify trends and make decisions without overwhelming the team with excessive detail or requiring interactive exploration.

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A live dashboard with interactive filters.

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A detailed spreadsheet with all data.

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A 20-slide presentation.