Section 1 - Instruction

Let's bring two big ideas together: combining data sources and ensuring your sample is representative. Getting the data combination right is only half the battle if the underlying sample is biased.

Engagement Message

What's a risk of combining a biased customer dataset with a complete sales dataset?

Section 2 - Practice

Type

Fill In The Blanks

Markdown With Blanks

To answer the question "Do customers from our loyalty program buy more expensive products?", you need to join the Loyalty table with the Sales table and the Products table.

The Loyalty and Sales tables can be joined on [[blank:Customer ID]]. The Sales and Products tables can be joined on [[blank:Product ID]].

Suggested Answers

  • Customer ID
  • Product ID
  • Order ID
  • Name
Section 3 - Practice

Type

Multiple Choice

Practice Question

You analyze survey data and find that 95% of respondents love your new feature. However, the survey was only sent to your top 10% of most active users. What is the main problem here?

A. The data has missing values B. The sample is biased and not representative C. The datasets were combined incorrectly D. The correlation is spurious

Suggested Answers

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