Confidence Intervals
In this part, we will build confidence intervals to estimate a range in which a population parameter is likely to lie (with a level of certainty specified by what is called the ‘confidence level’).
We will examine three possible cases of estimation:
- A true mean where the population standard deviation (σ) is known
- A true mean where the population standard deviation (σ) is unknown
- A true proportion or percentage for a population
We will also calculate the standard error (width of the interval on either side of the mean) as well as the sample size required when a maximum standard error size is specified/required.