Section 1 - Instruction

Now that you can form testable hypotheses, let's learn to compare groups! Business decisions often require comparing customer segments, time periods, or product performance.

This is where your hypotheses get tested against real data.

Engagement Message

What's one business comparison you've seen that led to an important decision?

Section 2 - Instruction

You can compare three main types of groups: customer segments (VIP vs regular), time periods (this month vs last month), or categories (Product A vs Product B).

Each comparison type answers different business questions.

Engagement Message

Which comparison type would help you understand seasonal sales patterns?

Section 3 - Instruction

Here's a crucial insight: not every numerical difference is meaningful. If Group A has 52% satisfaction and Group B has 51%, that 1% difference might be noise.

You need to distinguish between real differences and random variation.

Engagement Message

Why might a 1% difference in satisfaction scores not be meaningful?

Section 4 - Instruction

This is where statistical significance comes in. It helps you determine if a difference is likely real or just random chance.

Think of it as asking: "If I repeated this comparison 100 times, would I consistently see this difference?"

Engagement Message

What might happen if you made business decisions based on random variation?

Section 5 - Instruction

Sample size matters hugely for meaningful comparisons. Comparing 5 customers to 5 customers is less reliable than comparing 500 to 500.

Larger samples give you more confidence in your conclusions.

Engagement Message

Which sample size would give you greater confidence in a product comparison—3 customers or 300?

Section 6 - Instruction

Look for patterns that make business sense. If premium customers spend 40% more than regular customers, that's both statistically significant and logically meaningful.

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