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# Unit: Inference comparing two groups or populations

AP Stats:
DAT (BI)
,
DAT‑3 (EU)
,
UNC (BI)
,
UNC‑4 (EU)
,
VAR (BI)
,
VAR‑6 (EU)
,
VAR‑7 (EU)
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#### 0

Possible mastery points

## Confidence intervals for the difference between two proportions

AP Stats:
UNC (BI)
,
UNC‑4 (EU)
,
UNC‑4.I (LO), UNC‑4.I.1 (EK), UNC‑4.J (LO), UNC‑4.J.1 (EK), UNC‑4.K (LO), UNC‑4.K.1 (EK)

## Testing the difference between two proportions

AP Stats:
DAT (BI)
,
DAT‑3 (EU)
,
DAT‑3.C (LO), DAT‑3.C.1 (EK), DAT‑3.D (LO), DAT‑3.D.1 (EK), DAT‑3.D.2 (EK),
UNC (BI)
,
UNC‑4 (EU)
,
UNC‑4.N (LO), UNC‑4.N.1 (EK),
VAR (BI)
,
VAR‑6 (EU)
,
VAR‑6.H (LO), VAR‑6.H.1 (EK), VAR‑6.H.2 (EK), VAR‑6.H.3 (EK), VAR‑6.I (LO), VAR‑6.I.1 (EK), VAR‑6.J (LO), VAR‑6.J.1 (EK), VAR‑6.K (LO), VAR‑6.K.1 (EK)

#### Quiz 1

Level up on the above skills and collect up to 600 Mastery points

## Confidence intervals for the difference between two means

AP Stats:
UNC (BI)
,
UNC‑4 (EU)
,
UNC‑4.V (LO), UNC‑4.V.1 (EK), UNC‑4.V.2 (EK), UNC‑4.W (LO), UNC‑4.W.1 (EK), UNC‑4.X (LO), UNC‑4.X.1 (EK), UNC‑4.X.2 (EK), UNC‑4.Y (LO), UNC‑4.Y.1 (EK), UNC‑4.Y.2 (EK)
Practice
Conditions for inference on two meansGet 3 of 4 questions to level up!

## Testing the difference between two means

AP Stats:
DAT (BI)
,
DAT‑3 (EU)
,
DAT‑3.H (LO), DAT‑3.H.1 (EK), DAT‑3.H.2 (EK),
UNC (BI)
,
UNC‑4 (EU)
,
UNC‑4.AA (LO), UNC‑4.AA.1 (LO),
VAR (BI)
,
VAR‑7 (EU)
,
VAR‑7.B (LO), VAR‑7.B.2 (EK), VAR‑7.C (LO), VAR‑7.C.2 (EK), VAR‑7.F (LO), VAR‑7.F.1 (EK), VAR‑7.G (LO), VAR‑7.G.1 (EK), VAR‑7.I (LO), VAR‑7.I.1 (EK)
Practice
Test statistic in a two-sample t testGet 3 of 4 questions to level up!
P-value in a two-sample t testGet 3 of 4 questions to level up!
Making conclusions about the difference of meansGet 3 of 4 questions to level up!

#### Quiz 2

Level up on the above skills and collect up to 600 Mastery points
Up next for you:

#### Unit test

Level up on all the skills in this unit and collect up to 1200 Mastery points!