Confidence intervals

Introduction to confidence intervals

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Confidence intervals and margin of error
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Confidence interval simulation
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Interpreting confidence level example
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Interpreting confidence levels and confidence intervals
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Confidence intervals for proportions

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Conditions for valid confidence intervals
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Conditions for confidence intervals worked examples
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Reference: Conditions for inference on a proportion
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Critical value (z*) for a given confidence level
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Example constructing and interpreting a confidence interval for p
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Interpreting a z interval for a proportion
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Determining sample size based on confidence and margin of error
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Practice

Conditions for a z interval for a proportionGet 3 of 4 questions to level up!
Finding the critical value z* for a desired confidence levelGet 3 of 4 questions to level up!
Calculating a z interval for a proportionGet 3 of 4 questions to level up!
Sample size and margin of error in a z interval for pGet 3 of 4 questions to level up!

Confidence intervals for means

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Introduction to t statistics
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Simulation showing value of t statistic
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Conditions for valid t intervals
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Reference: Conditions for inference on a mean
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Example finding critical t value
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Example constructing a t interval for a mean
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Confidence interval for a mean with paired data
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Making a t interval for paired data
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Interpreting a confidence interval for a mean
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Sample size for a given margin of error for a mean
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Practice

Conditions for a t interval for a meanGet 3 of 4 questions to level up!
Finding the critical value t* for a desired confidence levelGet 3 of 4 questions to level up!
Calculating a t interval for a meanGet 3 of 4 questions to level up!
Sample size and margin of error in a confidence interval for a meanGet 3 of 4 questions to level up!

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.