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Confidence intervals

AP Stats: UNC (BI), UNC‑4 (EU)
AP Stats: UNC (BI), UNC‑4 (EU), UNC‑4.A (LO), UNC‑4.A.1 (EK), UNC‑4.F (LO), UNC‑4.F.1 (EK), UNC‑4.F.2 (EK), UNC‑4.F.3 (EK), UNC‑4.F.4 (EK)
Confidence intervals and margin of errorConfidence interval simulationInterpreting confidence level exampleInterpreting confidence levels and confidence intervals
AP Stats: UNC (BI), UNC‑4 (EU), UNC‑4.A (LO), UNC‑4.A.1 (EK), UNC‑4.B (LO), UNC‑4.B.1 (EK), UNC‑4.B.2 (EK), UNC‑4.C (LO), UNC‑4.C.1 (EK), UNC‑4.C.2 (EK), UNC‑4.C.3 (EK), UNC‑4.C.4 (EK), UNC‑4.D (LO), UNC‑4.D.1 (EK), UNC‑4.D.2 (EK), UNC‑4.F (LO), UNC‑4.F.4 (EK), UNC‑4.G (LO), UNC‑4.G.1 (EK), UNC‑4.H (LO), UNC‑4.H.1 (EK), UNC‑4.H.2 (EK)
Conditions for valid confidence intervalsConditions for confidence intervals worked examplesReference: Conditions for inference on a proportionCritical value (z*) for a given confidence levelExample constructing and interpreting a confidence interval for pInterpreting a z interval for a proportionDetermining sample size based on confidence and margin of error
AP Stats: UNC (BI), UNC‑4 (EU), UNC‑4.O (LO), UNC‑4.O.1 (EK), UNC‑4.O.3 (EK), UNC‑4.P (LO), UNC‑4.P.1 (EK), UNC‑4.Q (LO), UNC‑4.Q.1 (EK), UNC‑4.Q.2 (EK), UNC‑4.Q.3 (EK), UNC‑4.R (LO), UNC‑4.R.1 (EK), UNC‑4.R.2 (EK), UNC‑4.T (LO), UNC‑4.T.1 (EK), UNC‑4.U (LO)
Introduction to t statisticsSimulation showing value of t statisticConditions for valid t intervalsReference: Conditions for inference on a meanExample finding critical t valueExample constructing a t interval for a meanConfidence interval for a mean with paired dataMaking a t interval for paired dataInterpreting a confidence interval for a meanSample size for a given margin of error for a mean

About this unit

Confidence intervals give us a range of plausible values for some unknown population parameter based on results from a sample. This unit covers confidence intervals for means and proportions using data from one sample.
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