A statistic describes a sample. Examples are in mean x̄ and standard deviation s. 

​A parameter describes a population. Examples are in population mean μ and standard deviation σ. 

Statistical inference uses sample statistics to make decisons about prediction about population parameter. 

A confidence interval speciices the possible values a statistics can take and their probabilities. 

A point estimate is a single number that is our "best guess' for the parameter. 

An interval estimate is an interval of numbers within which the parameter value is believed to fall. 

The margin of error mesausres how accurate the point estimate is likely to be in estimating a parameter. 

- It increases as the confidence level increases thereby creating a wider interval.

- Decreases as the sample size increases.