DAC Data Tools and Visualization

Question 1

What is SQL and why is it essential for data analysts?

Accepted Answer

Structured Query Language — the standard language for querying, manipulating, and managing relational databases

Answer

A spreadsheet application

Answer

A data visualization tool

Answer

A programming language for websites

Question 2

When should you use a bar chart versus a line chart?

Accepted Answer

Bar charts for comparing categories; line charts for showing trends over time

Answer

They are interchangeable for all data types

Answer

Bar charts only for financial data

Answer

Line charts only for scientific data

Question 3

What is a dashboard in data analytics?

Accepted Answer

An interactive visual display of key metrics and KPIs, providing at-a-glance monitoring of business performance

Answer

A car's instrument panel

Answer

A social media profile page

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A project management timeline

Question 4

What is Python's role in data analytics?

Accepted Answer

A versatile programming language with libraries (pandas, NumPy, matplotlib) for data manipulation, analysis, and visualization

Answer

A type of database

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A spreadsheet formula language

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A data storage format

Question 5

What is A/B testing in data-driven decision making?

Accepted Answer

Comparing two versions of something (webpage, email, feature) by randomly assigning users to each version and measuring outcomes

Answer

Testing version A before version B chronologically

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Grading tests on an A/B scale

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Alternating between two strategies daily

Question 6

What is data storytelling?

Accepted Answer

Combining data, visuals, and narrative to communicate analytical findings effectively to stakeholders

Answer

Writing fictional stories about data

Answer

Reading data reports aloud in meetings

Answer

Creating animated data presentations