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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)
Learn
Confidence intervals for the difference between two proportions
(Opens a modal)
Examples identifying conditions for inference on two proportions
(Opens a modal)
Calculating a confidence interval for the difference of proportions
(Opens a modal)
Practice
Conditions for inference on two proportionsGet 3 of 4 questions to level up!
Two-sample z interval for the difference of proportionsGet 3 of 4 questions to level up!

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)
Learn
Hypothesis test for difference in proportions
(Opens a modal)
Constructing hypotheses for two proportions
(Opens a modal)
Hypothesis test for difference in proportions example
(Opens a modal)
Comparing P value to significance level for test involving difference of proportions
(Opens a modal)
Confidence interval for hypothesis test for difference in proportions
(Opens a modal)
Practice
Writing hypotheses for testing the difference of proportionsGet 3 of 4 questions to level up!
Test statistic in a two-sample z test for the difference of proportionsGet 3 of 4 questions to level up!
P-value in a two-sample z test for the difference of proportionsGet 3 of 4 questions to level up!
Making conclusions about the difference of proportionsGet 3 of 4 questions to level up!

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)
Learn
Conditions for inference for difference of means
(Opens a modal)
Constructing t interval for difference of means
(Opens a modal)
Calculating confidence interval for difference of means
(Opens a modal)
Practice
Conditions for inference on two meansGet 3 of 4 questions to level up!
Two-sample t interval for the difference of means (calculator-active)Get 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)
Learn
Hypotheses for a two-sample t test
(Opens a modal)
Example of hypotheses for paired and two-sample t tests
(Opens a modal)
Two-sample t test for difference of means
(Opens a modal)
Conclusion for a two-sample t test using a P-value
(Opens a modal)
Conclusion for a two-sample t test using a confidence interval
(Opens a modal)
Practice
Writing hypotheses to test the difference of meansGet 3 of 4 questions to level up!
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
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Unit test

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About this unit

If a poll from one location shows 55% of voters support a measure, but a poll from another location shows 45% support, does that mean there is a difference between the two populations? We can make a confidence interval to estimate the difference, or do a significance test to see if the difference is significant. We'll use similar methods to compare the means of two groups.
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